./../../src/utilities.lsp

## sc/utilities [ Modules ]

[ Top ] [ Modules ]

NAME

     utilities

     File:             utilities.lsp

     Class Hierarchy:  none: no classes defined

     Version:          1.0.12

     Project:          slippery chicken (algorithmic composition)

     Purpose:          Various helper functions of a general nature.

     Author:           Michael Edwards: m@michael-edwards.org

     Creation date:    June 24th 2002

     $$ Last modified:  19:10:16 Wed Feb 24 2021 CET

     SVN ID: $Id$

## utilities/a-weighting [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DESCRIPTION

     Implementation of A-weighting loudness compensation.  Formula taken from
     http://en.wikipedia.org/wiki/A-weighting.  This doesn't take 1000Hz
     loudness into account, rather it implements the 40-phon Fletcher-Munson
     curve only.

ARGUMENTS

     The frequency in Hertz for which to find the loudness weighting.

OPTIONAL ARGUMENTS

     keyword aguments:
     - :expt. A power (exponent) to raise the result to in order to
        tame/exaggerate the curve (make the db weightings less/more
        extreme). This only really makes sense if :linear t though will work
        with db values also of course.  Values < 1 result in linear values
        closer to 1 (less extreme).  Values > 1 are further from 1. Default = NIL
        i.e. no exponential function.
     - :linear.  If T return amplitude values as linear scalers rather than
        logarithmic decibel values.  NB If this is NIL then returned values are
        likely to be negative (db) values.  Default = T.
     - :invert.  As the weighting routine tries to tell us what relative
        loudness we'll perceive given constant amplitudes, low and high
        frequencies will return negative values as we perceive them Xdb less
        than our most sensitive frequency area.  If :invert t, just flip this
        negatives to positives so that if :linear T you get a scaler to make
        lower/higher frequences equally loud as the most sensitive frequencies.

RETURN VALUE

     The linear or db weighting value for the given frequency.

EXAMPLE

    ;;; Decibels:
    (a-weighting 50 :invert nil :linear nil) => -30.274979
    (a-weighting 50 :invert t :linear nil) => 30.274979
    ;;; Linear amplitude scalers:
    (a-weighting 50) => 32.639904
    (a-weighting 50 :invert nil) => 0.030637344
    ;;; Exaggeration:
    (a-weighting 50 :expt 1.1) => 46.251286
    ;;; Smoothing:
    (a-weighting 50 :expt .5) => 5.7131343

    ;;; Looping through the MIDI note range by tritones returning decibel values:
    (loop for midi from 0 to 127 by 6
         for freq = (midi-to-freq midi)
         collect (list (midi-to-note midi)
                       (a-weighting freq :linear nil :invert nil)))
    =>
    ((C-1 -76.85258) (FS-1 -65.94491) (C0 -55.819363) (FS0 -46.71565)
     (C1 -38.714867) (FS1 -31.724197) (C2 -25.598646) (FS2 -20.247103)
     (C3 -15.622625) (FS3 -11.657975) (C4 -8.258142) (FS4 -5.358156)
     (C5 -2.9644737) (FS5 -1.1277018) (C6 0.13445985) (FS6 0.8842882) (C7 1.226917)
     (FS7 1.2351798) (C8 0.89729404) (FS8 0.09495151) (C9 -1.3861179)
     (FS9 -3.7814288))

    ;;; Similar but returning linear amplitude scalers:
    (loop for midi from 0 to 127 by 6
         for freq = (midi-to-freq midi)
         collect (list (midi-to-note midi) (a-weighting freq)))
    =>
    ((C-1 6960.316) (FS-1 1982.6475) (C0 617.9711) (FS0 216.6619) (C1 86.246864)
     (FS1 38.56647) (C2 19.051636) (FS2 10.288571) (C3 6.041312) (FS3 3.827355)
     (C4 2.5876594) (FS4 1.8531382) (C5 1.4067719) (FS5 1.1386365) (C6 0.9846389)
     (FS6 0.9032034) (C7 0.8682687) (FS7 0.86744314) (C8 0.9018521) (FS8 0.9891278)
     (C9 1.1730213) (FS9 1.5455086))

SYNOPSIS

    (defun a-weighting (f &key expt (linear t) (invert t))

## utilities/all-members [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DESCRIPTION

     Find out whether the members of the list given as the second argument are
     all present in the list given as the first argument.

ARGUMENTS

     - A list in which the members of the second argument will be sought.
     - A list whose members will be sought in the first argument.

     OPTIONAL ARGUMENT
     - A comparison function.

RETURN VALUE

     T or NIL.

EXAMPLE

    (all-members '(1 2 3 4 5 6 7) '(1 2 3 7))

    => T

SYNOPSIS

    (defun all-members (list test-list &optional (test #'equal))

## utilities/almost-flatten [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DATE

     September 4th 2013

DESCRIPTION

     Similar to flatten but allows one level of nesting

ARGUMENTS

     A list with an arbitrary level of nesting.

RETURN VALUE

     A list with a maximum of one level of nesting

EXAMPLE

    (almost-flatten '((1 (2 3 4) (5 (6 7) (8 9 10 (11) 12)) 13) 14 15 (16 17)))
    => (1 (2 3 4) 5 (6 7) 8 9 10 (11) (12) (13) 14 15 (16 17))

SYNOPSIS

    (defun almost-flatten (nested-list)

## utilities/almost-zero [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DESCRIPTION

     Return T if a given decimal is within 0.000001 of 0.0.

ARGUMENTS

     - A number.

OPTIONAL ARGUMENTS

     - A number that is a user-specified difference for the comparison test.

RETURN VALUE

     T if the number is within the tolerance difference to zero, otherwise NIL.

EXAMPLE

    (almost-zero 0.0000007)

    => T

SYNOPSIS

    (defun almost-zero (num &optional (tolerance 0.000001))

## utilities/amp2db [ Methods ]

[ Top ] [ utilities ] [ Methods ]

DESCRIPTION

     Convert a standard digital amplitude value (>0.0 to 1.0) to a corresponding
     decibel value.

ARGUMENTS

     - A decimal number between >0.0 and 1.0.

RETURN VALUE

     A decimal number that is a value in decibel.

EXAMPLE

    (amp2db 0.3)

    => -10.457575

SYNOPSIS

    (defmacro amp2db (amp)

## utilities/amplitude-to-dynamic [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DESCRIPTION

     Convert a specified digital amplitude between 0.0 and 1.0 to a
     corresponding dynamic between niente and ffff.

ARGUMENTS

     - A decimal number between 0.0 and 1.0.

OPTIONAL ARGUMENTS

     - T or NIL to indicate whether to print a warning if the specified
       amplitude is <0.0 or >1.0. T = warn. Default = T.

RETURN VALUE

     A symbol that is a dynamic level.

EXAMPLE

    (amplitude-to-dynamic 0.3)

    => PP

SYNOPSIS

    (defun amplitude-to-dynamic (amp &optional (warn t))

## utilities/auto-scale-env [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DATE

     August 29th 2013

DESCRIPTION

     Automatically scale both the x and y values of an envelope to fit within
     the given ranges. Normally we'll assume that the minimum and maximum Y
     values are present in the original envelope and so the automatically scaled
     envelope will represent these with the new minimum and maximum
     values. However sometimes an envelope doesn't range over the possible
     extremes, for example (0 .3 100 .6) where the y range is from 0 to 1. If
     this is the case and you need a scaled envelope to take this into account,
     then how is the original envelopes minimum and maximum values to the
     keyword argument :orig-y-range.

ARGUMENTS

     - The envelope: a list of x y pairs

OPTIONAL ARGUMENTS

     keyword arguments:
     - :x-min: The new minimum (starting) x value
     - :x-max: The new maximum (last) x value
     - :y-min: The new minimum (not necessarily starting!) y value
     - :y-max: The new maximum (not necessarily starting!) y value
     - :orig-y-range: a two-element list specifying the original envelope's
       minimum and maximum values (see above).

RETURN VALUE

     The new envelope (list).

EXAMPLE

    (auto-scale-env '(0 0 10 1))
    =>
    (0.0 0.0 100.0 10.0)

    (auto-scale-env '(-1 0 .3 -3 1 1) :y-min 5 :y-max 6 :x-min 2)
    =>
    (2.0 5.75 65.7 5.0 100.0 6.0))

    (auto-scale-env '(0 1 5 1.5 7 0 10 1) :y-min -15 :y-max -4)
    =>
    (0.0 -7.6666665 50.0 -4.0 70.0 -15.0 100.0 -7.6666665))

    (auto-scale-env '(0 .5 100 .5) :y-min 1 :y-max 2)
    => (0.0 1.0 100.0 1.0)

    (auto-scale-env '(0 .5 100 .5) :y-min 1 :y-max 2 :orig-y-range '(0 1))
    => (0.0 1.5 100.0 1.5)

SYNOPSIS

    (defun auto-scale-env (env &key
                                 (x-min 0.0) (x-max 100.0)
                                 (y-min 0.0) (y-max 10.0)
                                 orig-y-range)

## utilities/between [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DESCRIPTION

     Return a random number between two specified numbers. If the two numbers are
     integers, the random selection is inclusive. If either are floating-point
     (decimal) numbers, the result will be a float between the first (inclusive)
     and just less than the second (i.e. exclusive).

ARGUMENTS

     - A first, lower, number.
     - A second, higher, number.

     NB: The first number must always be lower than the second.

OPTIONAL ARGUMENTS

     - T or NIL to indicate whether the random seed should be fixed.
     - T or NIL to indicate whether, when fixed-random is set to T, we should
       reset the random number generator (to guarantee the same random
       sequences). This would generally only be called once, perhaps at the
       start of a generation procedure.

RETURN VALUE

     An integer if both numbers are integers, or a float if one or both are
     decimal numbers.

EXAMPLE

    ;;; Using the defaults. This will produce a different result each time.
    (loop repeat 10 collect (between 1 100))

    => (43 63 26 47 28 2 99 93 66 23)

    ;;; Setting fixed-random to T and using zerop to reset the random when i is 0
    (loop repeat 5
       collect (loop for i from 0 to 9 collect (between 1 100 t (zerop i))))

    => ((93 2 38 81 43 19 70 18 44 26) (93 2 38 81 43 19 70 18 44 26)
        (93 2 38 81 43 19 70 18 44 26) (93 2 38 81 43 19 70 18 44 26)
        (93 2 38 81 43 19 70 18 44 26))

SYNOPSIS

    (defun between (low high &optional fixed-random restart)

## utilities/between-extremes [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DATE

     April 23rd 2016, Edinburgh

DESCRIPTION

     Given a <progress> value of between 0 and 1, we'll return whatever that
     proportion is of the difference between <min> and <max> added to min. NB No
     randomness here.

ARGUMENTS

     - the minimum value (returned when <progress> is 0.0)
     - the maximum value (returned when <progress> is 1.0)
     - a value between

RETURN VALUE

     a number between min and max

EXAMPLE

    (BETWEEN-EXTREMES 0.5 1 0.5)
    ==> 0.75
    (BETWEEN-EXTREMES 0.5 1 0.9)
    ==> 0.95

SYNOPSIS

    (defun between-extremes (min max progress)

## utilities/combine-into-symbol [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DESCRIPTION

     Combine a sequence of elements of any combination of type string, number,
     or symbol into a symbol.

ARGUMENTS

     - A sequence of elements.

RETURN VALUE

     A symbol as the primary value, with the length of that symbol as a
     secondary value.

EXAMPLE

    (combine-into-symbol "test" 1 'a)

    => TEST1A, 6

SYNOPSIS

    (defun combine-into-symbol (&rest params)

## utilities/db2amp [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DESCRIPTION

     Convert a decibel value to a standard digital amplitude value (>0.0 to 1.0),
     whereby 0dB = 1.0.

ARGUMENTS

     - A number that is a value in decibel.

RETURN VALUE

     A decimal number between >0.0 and 1.0.

EXAMPLE

    (db2amp -3)

    => 0.70794576

SYNOPSIS

    (defmacro db2amp (db)

## utilities/decimal-places [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DATE

     19-Mar-2012

DESCRIPTION

     Round the given number to the specified number of decimal places.

ARGUMENTS

     - A number.
     - An integer that is the number of decimal places to which to round the
       given number.

RETURN VALUE

     A decimal number.

EXAMPLE

    (decimal-places 1.1478349092347 2)

    => 1.15

SYNOPSIS

    (defun decimal-places (num places)

## utilities/decimate-env [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DESCRIPTION

     Reduce the number of x,y pairs in an envelope.  In every case the envelope
     is first stretched along the x-axis to fit the new number of points
     required.  Then we proceed by one of three methods:

     1) average: for every new output x value, interpolate 100 times from -0.5
     to +0.5 around the point, then average the y value.  This will catch
     clustering but round out spikes caused by them

     2) points: also an averaging method but only using the existing points in
     the original envelope (unless none is present for a new x value, whereupon
     interpolation is used): Take an average of the (several) points nearest the
     new output point. This might not recreate the extremes of the original
     envelope but clustering is captured, albeit averaged.

     3) interpolate: for each new output point, interpolate the new y value from
     the original envelope.  This will leave out details in the case of
     clustering, but accurately catch peaks if there are enough output points.

     In each case we create an even spread of x values, rather than clustering
     where clusters exist in the original.

ARGUMENTS

     - the original envelope (list of x,y values on any scales).
     - the number of points required in the output list.

OPTIONAL ARGUMENTS

     - the method to be applied (symbol): 'points, 'average, 'interpolate.
       Default = 'points.

RETURN VALUE

     A list representing the x,y values of the new envelope

EXAMPLE

    (decimate-env '(0 0 4 4 5 5 5.1 5.1 5.3 1 5.6 5.6 6 6 10 10) 6)
    =>
    (0.0 0.0 1 2.0 2 4.5 3 4.425 4 8.0 5.0 10.0)

SYNOPSIS

    (defun decimate-env (env num-points &optional (method 'points))

## utilities/down-up [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DATE

     May 8th 2016

DESCRIPTION

     This is a routine used in morphing maps but may be useful elsewhere. It
     interpolates between two numbers over a given number of steps before
     returning back to the first number.

ARGUMENTS

     - the number of steps over which the procedure should interpolate

OPTIONAL ARGUMENTS

     keyword arguments:
     - :down. T or NIL: whether to first descend before ascending. Default = T
     - :up. T or NIL: whether to ascend after descending. Default = T
     - :start. The number to start at. Default = 1.0
     - :target. The number to interpolate towards. Default = 0.0.
     - :cons. Whether to return :start as the first number in the result list.
     - :butlast. Whether to omit the :start when ascending. Default = T.

RETURN VALUE

     A list of numbers.

EXAMPLE

    (mapcar #'(lambda (x) (decimal-places x 2)) (down-up 20))
    --> (0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0.0 0.09 0.18 0.27 0.36 0.45 0.55 0.64
         0.73 0.82 0.91)
    (mapcar #'(lambda (x) (decimal-places x 2)) (down-up 20 :cons t))
    --> (1.0 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8
         0.9)
    (mapcar #'(lambda (x) (decimal-places x 2)) (down-up 20 :butlast nil))
    --> (0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9
         1.0)

SYNOPSIS

    (defun down-up (steps &key (down t) (up t) (start 1.0d0) (target 0.0d0)
                            (cons nil) (butlast t))

## utilities/dynamic-to-amplitude [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DESCRIPTION

     Convert a symbol that is a dynamic level between niente and ffff to a
     corresponding digital amplitude value between 0.0 and 1.0.

ARGUMENTS

     - A symbol that is a dynamic level between niente and fff.

OPTIONAL ARGUMENTS

     - T or NIL to indicate whether to print a warning when the symbol specified
       is not recognized as a dynamic. T = warn. Default = T.

RETURN VALUE

     A decimal number between 0.0 and 1.0.

EXAMPLE

    (dynamic-to-amplitude 'fff)

    => 0.9

SYNOPSIS

    (defun dynamic-to-amplitude (dynamic &optional (warn t))

## utilities/econs [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DESCRIPTION

     Add a specified element to the end of an existing list.

ARGUMENTS

     - A list.
     - An element to add to the end of the list.

RETURN VALUE

     A new list.

EXAMPLE

    (econs '(1 2 3 4) 5)

    =>  '(1 2 3 4 5)

SYNOPSIS

    (defun econs (list new-back)

## utilities/env-plus [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DESCRIPTION

     Increase all y values of a given list of break-point pairs by a specified
     amount.

ARGUMENTS

     - An envelope in the form of a list of break-point pairs.
     - A number that is the amount by which all y values of the given envelope
       are to be increased.

RETURN VALUE

     A list of break-point pairs.

EXAMPLE

    (env-plus '(0 0 25 11 50 13 75 19 100 23) 7.1)

    => (0 7.1 25 18.1 50 20.1 75 26.1 100 30.1)

SYNOPSIS

    (defun env-plus (env add)

## utilities/env-symmetrical [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DESCRIPTION

     Create a new list of break-point pairs that is symmetrical to the original
     around a specified center. If no center is specified, the center value
     defaults to 0.5

ARGUMENTS

     - An envelope in the form of a list of break-point pairs.

OPTIONAL ARGUMENTS

     - A number that is the center value around which the values of the
       new list are to be symmetrical.
     - A number that is to be the minimum value for the y values returned.
     - A number that is to be the maximum value for the y values returned.

RETURN VALUE

     An envelope in the form of a list of break-point pairs.

EXAMPLE

    ;;; Default center is 0.5
    (env-symmetrical '(0 0 25 11 50 13 75 19 100 23))

    => (0 1.0 25 -10.0 50 -12.0 75 -18.0 100 -22.0)

    ;; Specifying a center of 0
    (env-symmetrical '(0 0 25 11 50 13 75 19 100 23) 0)

    => (0 0.0 25 -11.0 50 -13.0 75 -19.0 100 -23.0)

    ;;; Specifying minimum and maximum y values for the envelope returned
    (env-symmetrical '(0 0 25 11 50 13 75 19 100 23) 0 -20 -7)

    => (0 -7 25 -11.0 50 -13.0 75 -19.0 100 -20)

SYNOPSIS

    (defun env-symmetrical (env &optional (centre .5)
                            (min most-negative-double-float)
                            (max most-positive-double-float))

## utilities/env2gnuplot [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DATE

     24th December 2013

DESCRIPTION

     Write a data file of x,y envelope values for use with gnuplit.  Once called
     start gnuplot and issue commands such as:
     gnuplot> set terminal postscript default
     gnuplot> set output '/tmp/env.ps'
     gnuplot> plot '/tmp/env.txt' with lines.

ARGUMENTS

     - The envelope as the usual list of x y pairs

OPTIONAL ARGUMENTS

     - The pathname of the data file to write.  Default = "/tmp/env.txt".

RETURN VALUE

     Always T

SYNOPSIS

    (defun env2gnuplot (env &optional (file "/tmp/env.txt"))

## utilities/envelope-boundaries [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DESCRIPTION

     Find sharp changes in envelope values. These are defined as when a y value
     rises or falls over 30% (by default) of it's overall range within 5%
     (again, by default) of its overall x axis range.

ARGUMENTS

     The envelope (a list of x y pairs).

OPTIONAL ARGUMENTS

     - jump-threshold: the minimum percentage change in y value that is deemed a
       sharp change.
     - steepness-min: the maximum percentage of the overall x axis that
       constitutes a 'quick' change.

RETURN VALUE

     A list of x values at which boundaries are deemed to lie.

EXAMPLE

    (ENVELOPE-BOUNDARIES '(0 10 20 10 21 3 25 4 26 9 50 7 51 1 55 2 56 7 70 10
                         100 10))
    --> (21 26 51 56)

SYNOPSIS

    (defun envelope-boundaries (envelope &optional (jump-threshold 30)
                                (steepness-min 5))

## utilities/equal-within-tolerance [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DESCRIPTION

     Test whether the difference between two decimal numbers falls within a
     specified tolerance.

     This test is designed to compensate for calculation discrepancies caused by
     floating-point errors (such as 2.0 vs. 1.9999997), in which the equations
     should yield equal numbers. It is intended to be used in place of = in such
     circumstances.

ARGUMENTS

     - A first number.
     - A second number.

OPTIONAL ARGUMENTS

     - A decimal value that is the maximum difference allowed between the two
       numbers that will still return T. Default = 0.000001d0.

RETURN VALUE

     T if the two tested numbers are equal within the specified tolerance,
     otherwise NIL.

EXAMPLE

    ;; An example of floating-point error
    (loop for i from 0.0 below 1.1 by 0.1 collect i)

    => (0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.70000005 0.8000001 0.9000001 1.0000001)

    ;; Using =
    (loop for i from 0.0 below 1.1 by 0.1
       for j in '(0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0)
       collect (= i j))

    => (T T T T T T T NIL NIL NIL NIL)

    ;; Using equal-within-tolerance
    (loop for i from 0.0 below 1.1 by 0.1
       for j in '(0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0)
       collect (equal-within-tolerance i j))

    => (T T T T T T T T T T T)

SYNOPSIS

    (defun equal-within-tolerance (a b &optional (tolerance 0.000001d0))

## utilities/exaggerate-env [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DESCRIPTION

     Makes the y values in an envelope more radically pushed towards its
     extremes. Y values below the mid-point will be pushed downwards; those
     above will be pushed upwards. The opposite can be accomplished by making
     the exponent argument > 1 (see below).

ARGUMENTS

     - the envelope: a list of numbers representing an envelope: x y pairs
     - the exponent: this determines the amount of
       exaggeration. Counterintuitively perhaps, the lower values are than 1 the
       more exaggeration takes place. Values > 1 will mean the opposite:
       understated y values, if you will.

OPTIONAL ARGUMENTS

     - easy-expt: because of the counterintuitive nature of the exponent, you
       can pass values between -10 and +10 if this third argument is T. This
       will be scaled to useful though not over-extreme exponents of 1.9 (-10)
       to .1 (+10) with 0 equating to an exponent of 1, i.e. no change.

RETURN VALUE

     The new exaggerated envelope (a list).

EXAMPLE

    (exaggerate-env '(0 0 50 .8 100 1) 1.9)
    --> (0 0.0 50 0.6894338 100 1.0)
    (exaggerate-env '(0 0 50 .8 100 1) .1)
    --> (0 0.0 50 0.9751001 100 1.0)
    (exaggerate-env '(0 0 50 .8 100 1) -10)
    --> (0 0.0 50 83.19083 100 1.0)
    (exaggerate-env '(0 0 50 .8 100 1) -10 t)
    --> (0 0.0 50 0.6894338 100 1.0)
    (exaggerate-env '(0 0 50 .8 100 1) 0 t)
    --> (0 0.0 50 0.8 100 1.0)
    (exaggerate-env '(0 0 50 .8 100 1) 10 t)
    --> (0 0.0 50 0.9751001 100 1.0)

SYNOPSIS

    (defun exaggerate-env (env expt &optional easy-expt)

## utilities/factor [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DESCRIPTION

     Boolean test to check if a specified number is a multiple of a second
     specified number.

ARGUMENTS

     - A number that will be tested to see if it is a multiple of the second
       number.
     - A second number that is the base number for the factor test.

RETURN VALUE

     T if the first number is a multiple of the second number, otherwise NIL.

EXAMPLE

    (factor 14 7)

    => T

SYNOPSIS

    (defun factor (num fac)

## utilities/flatten [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DESCRIPTION

     Return a list of nested lists of any depth as a flat list.

ARGUMENTS

     - A list of nested lists.

RETURN VALUE

     A flat list.

EXAMPLE

    (flatten '((1 (2 3 4) (5 (6 7) (8 9 10 (11) 12)) 13) 14 15 (16 17)))

    => (1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17)

SYNOPSIS

    (defun flatten (nested-list)

## utilities/force-length [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DATE

     03-FEB-2011

DESCRIPTION

     Create a new a list of a specified new length by adding or removing items
     at regular intervals from the original list. If adding items and the list
     contains numbers, linear interpolation will be used, but only between two
     adjacent items; i.e. not with a partial increment.

     NB: The function can only create new lists that have a length between 1 and
         1 less than double the length of the original list.

ARGUMENTS

     - A flat list.
     - A number that is the new length of the new list to be derived from the
       original list. This number must be a value between 1 and 1 less than
       double the length of the original list.

RETURN VALUE

EXAMPLE

    ;;; Shortening a list
    (force-length (loop for i from 1 to 100 collect i) 17)

    => (1 7 13 20 26 32 39 45 51 57 63 70 76 82 89 95 100)

    ;;; Lengthening a list
    (force-length (loop for i from 1 to 100 collect i) 199)

    => (1 1.5 2 2.5 3 3.5 4 4.5 5 5.5 6 6.5 7 7.5 8 8.5 9 9.5 10 10.5 11 11.5 12
        12.5 13 13.5 14 14.5 15 15.5 16 16.5 17 17.5 18 18.5 19 19.5 20 20.5 21
        21.5 22 22.5 23 23.5 24 24.5 25 25.5 26 26.5 27 27.5 28 28.5 29 29.5 30
        30.5 31 31.5 32 32.5 33 33.5 34 34.5 35 35.5 36 36.5 37 37.5 38 38.5 39
        39.5 40 40.5 41 41.5 42 42.5 43 43.5 44 44.5 45 45.5 46 46.5 47 47.5 48
        48.5 49 49.5 50 50.5 51 51.5 52 52.5 53 53.5 54 54.5 55 55.5 56 56.5 57
        57.5 58 58.5 59 59.5 60 60.5 61 61.5 62 62.5 63 63.5 64 64.5 65 65.5 66
        66.5 67 67.5 68 68.5 69 69.5 70 70.5 71 71.5 72 72.5 73 73.5 74 74.5 75
        75.5 76 76.5 77 77.5 78 78.5 79 79.5 80 80.5 81 81.5 82 82.5 83 83.5 84
        84.5 85 85.5 86 86.5 87 87.5 88 88.5 89 89.5 90 90.5 91 91.5 92 92.5 93
        93.5 94 94.5 95 95.5 96 96.5 97 97.5 98 98.5 99 99.5 100)

SYNOPSIS

    (defun force-length (list new-len)

## utilities/get-clusters [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DESCRIPTION

     Takes a list with (ascending) numbers and creates sublists of those numbers
     within <threshold> of each other.

ARGUMENTS

     A list of (ascending) numbers. NB Though the numbers don't have to be in
     ascending order, the design application of the function makes most sense if
     they are.

OPTIONAL ARGUMENTS

     The maximum distance between two numbers in order for them to be considered
     as part of the same cluster.

RETURN VALUE

     A list with clusters in sublists.

EXAMPLE

    (get-clusters '(24 55 58 59 60 81 97 102 106 116 118 119 145 149 151 200 210
                    211 214 217 226 233 235 236 237 238 239 383 411 415 419))
    --> (24 (55 58 59 60) 81 (97 102 106) (116 118 119) (145 149 151) 200
            (210 211 214 217) 226 (233 235 236 237 238 239) 383 (411 415 419))

    (get-clusters '(0 .1 .3 .7 1.5 1.55 2 4.3 6.3 6.4) 1)
    --> ((0 0.1 0.3 0.7 1.5 1.55 2) 4.3 (6.3 6.4))

    (get-clusters '(0 .1 .3 .7 1.5 1.55 2 4.3 6.3 6.4) 0.5)
    --> ((0 0.1 0.3 0.7) (1.5 1.55 2) 4.3 (6.3 6.4))

SYNOPSIS

    (defun get-clusters (list &optional (threshold 5))

## utilities/get-harmonics [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DESCRIPTION

     Return a list of the harmonic partial frequencies in Hertz from a
     specified (usually fundamental) frequency.

ARGUMENTS

     - A number that is the fundamental or starting frequency in Hertz.

OPTIONAL ARGUMENTS

     keyword arguments
     - :start-partial. An integer that is the number of the first harmonic
        partial to return. Default = 1.
     - :min-freq. A number that is the lowest frequency in Hertz to
       return. Default = 20.
     - :max-freq. A number that is the highest frequency in Hertz to
       return. Default = 20000.
     - :start-freq-is-partial.  Rather than treating the first argument as the
       fundamental, treat it as the partial number indicated by this argument.
       Default = 1.
     - :max-results.  The maximum number of harmonics to return.  Default =
        most-positive-fixnum
     - :skip. The increment for the harmonics.  If 1, then we ascend the
        harmonics series one partial at a time; 2 would mean skipping every other
        Default = 1.
     - :pitches. Return a list of pitch objects instead of frequencies. Default =
       NIL.
     - :notes. Return a list of 2-element sublists: note symbols in the
       chromatics scale, with cent deviations

RETURN VALUE

     A list of numbers that are the frequencies in Hertz of harmonic partials
     above the same fundamental frequency, or with the respective keyword, as
     pitch objects or note symbols

EXAMPLE

    ;;; Get the first 15 harmonic partials above a fundamental pitch of 64 Hertz,
    ;;; starting with partial 2, and specifying an upper cut-off of 1010 Hz.

    (get-harmonics 63 :start-partial 2 :max-freq 1010)

    => (126 189 252 315 378 441 504 567 630 693 756 819 882 945 1008)

SYNOPSIS

    (defun get-harmonics (start-freq &key (start-partial 1) (min-freq 20)
                                       (start-freq-is-partial 1) (max-freq 20000)
                                       (skip 1)
                                       pitches notes
                                       (max-results most-positive-fixnum))

## utilities/get-parameters [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DATE

     January 29th 2021

DESCRIPTION

     A general routine for searching text files for parameters and their
     values. Here we search a file line by line, matching parameters and
     returning them in a list of parameter-value pairs. This is limited, however,
     to one parameter per line, and values of one word (i.e. numbers, strings,
     etc. not containing space).

ARGUMENTS

     - the text file to search
     - either a single string or list thereof to search for (case-sensitive)
     - the separator character which divides the parameter name from its value

OPTIONAL ARGUMENTS

     - the parameter-value separator (character)

RETURN VALUE

     A list of parameter-value pairs

EXAMPLE

    ;;; search a reaper file, where parameters are followed simply by space rather
    ;;; than = or : E.g. a current reaper file has lines like:
          SNAPOFFS 0
          LENGTH 0.36292517006803
          LOOP 1
          ALLTAKES 0
          FADEIN 2 0 0 2 0 1 1
          FADEOUT 2 0 0 2 0 -1 -1
          MUTE 0 0
          MIXFLAG 1
          BEAT 2
          SEL 1
          IGUID {3B79D8DF-AC08-EC4F-B93C-CAFE24FA1CBB}
          IID 3
          NAME sunni-mosque.wav
          VOLPAN 1 0 1 -1
          SOFFS 0.67933106575964
          PLAYRATE 1 1 0 -1 0 0.0025
    ;;; hence:
    (get-parameters "~/projects/sndfilenet/reaper/sunni-mosque-split.RPP"
                    '("SOFFS" "LENGTH") #\ )
    -->
    362 parameters read
    (("LENGTH" 0.36292517) ("SOFFS" 0.67933106) ("LENGTH" 0.38848072)
     ("SOFFS" 1.0422562) ("LENGTH" 1.4923356) ("SOFFS" 1.430737)
     ("LENGTH" 1.9968253) ("SOFFS" 2.9230726) ("LENGTH" 0.5023356)
     ("SOFFS" 4.919898) ("LENGTH" 0.4907483) ("SOFFS" 5.4222336)
     ("LENGTH" 0.17068027) ("SOFFS" 5.912982) ("LENGTH" 3.6765532)
    ...

SYNOPSIS

    (defun get-parameters (file parameters &optional (separator #\=))

## utilities/get-sublist-indices [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DESCRIPTION

     Get the starting position of sublists within a list as though the complete
     set of items were a flat list.

ARGUMENTS

     - A list of lists.

RETURN VALUE

     A list of integers that are the indices of the sublists.

EXAMPLE

    (get-sublist-indices '((1 2) (3 4 5 6) (7 8 9) (10 11 12 13 14) (15)))

    => (0 2 6 9 14)

SYNOPSIS

    (defun get-sublist-indices (list)

## utilities/get-sublist-lengths [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DESCRIPTION

     Get the lengths of all sublists in a given list.

ARGUMENTS

     - A list of lists.

OPTIONAL ARGUMENTS

     - T or NIL to indicate whether to first remove zeros caused by empty
       sublists from the result.

RETURN VALUE

     A list of integers.

EXAMPLE

    ;; Straightforward usage allows zeros in the result
    (get-sublist-lengths '((1 2) (3 4 5 6) (7 8 9) (10 11 12 13 14) ()))

    => (2 4 3 5 0)

    ;; Setting the optional argument to T removes zeros from the result

    (get-sublist-lengths '((1 2) (3 4 5 6) (7 8 9) (10 11 12 13 14) ()) t)

    => (2 4 3 5)

SYNOPSIS

    (defun get-sublist-lengths (list &optional (remove-zeros nil))

## utilities/hailstone [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DESCRIPTION

     Implementation of the Collatz conjecture (see
     http://en.wikipedia.org/wiki/Collatz_conjecture)

     The Collatz conjecture suggests that by starting with a given number, and
     if it is even dividing it by two or if it is odd multiplying it by three
     and adding one, then repeating with the new result, the process will
     eventually always result in one.

ARGUMENTS

     - A number to start with.

RETURN VALUE

     A list of the results collected from each iteration starting with the
     specified number and ending with one.

EXAMPLE

    (hailstone 11)

    => (11 34 17 52 26 13 40 20 10 5 16 8 4 2 1)

SYNOPSIS

    (defun hailstone (n)

## utilities/hz2ms [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DESCRIPTION

     Convert a frequency in Hertz to the equivalent number of milliseconds.

ARGUMENTS

     - A number that is a Hertz frequency.

RETURN VALUE

     A number that is the millisecond equivalent of the specified Hertz
     frequency.

EXAMPLE

    (hz2ms 261.63)

    => 3.8221915

SYNOPSIS

    (defun hz2ms (hertz)

## utilities/interleave [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DESCRIPTION

     Interleave the elements of an aribitrary number of lists. Should the lists
     not be of the same length, this function will only use up as many elements
     as in the shortest list.

ARGUMENTS

     As many lists as need to be interleaved.

RETURN VALUE

     A new list of interleaved elements.

EXAMPLE

    (INTERLEAVE '(1 2 3 4 5) '(a b c d) '(x y z))
    --> (1 A X 2 B Y 3 C Z)

    (INTERLEAVE '(1 2 3 4 5) '(a b c d e) '(v w x y z))
    --> (1 A V 2 B W 3 C X 4 D Y 5 E Z)

SYNOPSIS

    (defun interleave (&rest lists)

## utilities/interpolate [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DESCRIPTION

     Get the interpolated value at a specified point within an envelope. The
     envelope must be specified in the form of a list of break-point pairs.

ARGUMENTS

     - A number that is the point within the specified envelope for which to
       return the interpolated value.
     - A list of break-point pairs.

OPTIONAL ARGUMENTS

     keyword arguments:
     - :scaler. A number that is the factor by which to scale the values of
       the break-point pairs in the given envelope before retrieving the
       interpolated value. Default = 1.
     - :exp. A number that is the exponent to which the result should be
       raised. Default = 1.
     - :warn. T or NIL to indicate whether the method should print a warning if
       the specified point is outside of the bounds of the x-axis specified in
       the list of break-point pairs. T = warn. Default = T.

RETURN VALUE

EXAMPLE

    ;;; Using the defaults
    (interpolate 50 '(0 0 100 1))

    => 0.5

    ;;; Specifying a different scaler
    (interpolate 50 '(0 0 100 1) :scaler 2)

    => 1.0

    ;;; Specifying a different exponent by which the result is to be raised
    (interpolate 50 '(0 0 100 1) :exp 2)

    => 0.25

SYNOPSIS

    (defun interpolate (point env &key (scaler 1) (exp 1) (warn t))

## utilities/invert-env [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DATE

     June 15th 2017, Edinburgh

DESCRIPTION

     Invert an envelope so that its maximum value becomes its minimum,
     vice-versa, and everything inbetween.

ARGUMENTS

     A list of X-Y breakpoint pairs

RETURN VALUE

     A list of X-Y breakpoint pairs exhibiting the inversion.

EXAMPLE

    (invert-env '(0 0 100 1)) -> (0 1.0 100 0.0)
    (invert-env '(0 .3 40 .4 100 .9)) -> (0 0.9 40 0.79999995 100 0.3)
    (invert-env '(0 -.9 40 .4 100 .9)) -> (0 0.9 40 -0.39999998 100 -0.9)

SYNOPSIS

    (defun invert-env (env)

## utilities/list-to-string [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DESCRIPTION

     Convert a list to a string.

ARGUMENTS

     - A list.

OPTIONAL ARGUMENTS

     - A string that will serve as a separator between the elements.
       Default = " ".
     - T or NIL to indicate whether a list value of NIL is to be returned as
       "NIL" or NIL. T = "NIL" as a string. Default = T.

RETURN VALUE

EXAMPLE

    ;;; Using defaults
    (list-to-string '(1 2 3 4 5))

    => "1 2 3 4 5"

    ;;; Specifying a different separator
    (list-to-string '(1 2 3 4 5) "-")

    => "1-2-3-4-5"

    ;;; A NIL list returns "NIL" as a string by default
    (list-to-string NIL)

    => "nil"

    ;;; Setting the second optional argument to NIL returns a NIL list as NIL
    ;;; rather than as "NIL" as a string
    (list-to-string NIL "" nil)

    => NIL

SYNOPSIS

    (defun list-to-string (list &optional (separator " ") (nil-as-string t))

## utilities/logarithmic-steps [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DESCRIPTION

     Create a list of numbers progressing from the first specified argument to
     the second specified argument over the specified number of steps using an
     exponential curve rather than linear interpolation.

ARGUMENTS

     - A number that is the starting value in the resulting list.
     - A number that is the ending value in the resulting list.
     - An integer that will be the length of the resulting list - 1.

OPTIONAL ARGUMENTS

     - A number that will be used as the exponent when determining the
       exponential interpolation between values. Default = 2.

RETURN VALUE

     A list of numbers.

EXAMPLE

    (logarithmic-steps 1 100 19)

    => (1.0 1.3055556 2.2222223 3.75 5.888889 8.638889 12.0 15.972222 20.555555
        25.75 31.555555 37.97222 45.0 52.63889 60.88889 69.75 79.22222 89.30556
        100.0)

SYNOPSIS

    (defun logarithmic-steps (low high num-steps &optional (exponent 2))

## utilities/middle [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DESCRIPTION

     Get the number value that is middle of two number values.

ARGUMENTS

     - A first number.
     - A second number.

RETURN VALUE

     A number.

EXAMPLE

    (middle 7 92)

    => 49.5

SYNOPSIS

    (defun middle (lower upper)

## utilities/mins-secs-to-secs [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DESCRIPTION

     Derive the number of seconds from a minutes-seconds value that is indicated
     as a string of the form "0:00.000" or a two-item list in the form '(minutes
     seconds) or three-item list in the form '(minutes seconds milliseconds)

ARGUMENTS

     - A time in minutes and seconds, as described above.

OPTIONAL ARGUMENTS

     - if a string is to be passed, then a character that denotes the separator
     between minutes and seconds. Default = #\:

RETURN VALUE

     A decimal number that is a number in seconds.

EXAMPLE

    (mins-secs-to-secs '(2 1))
    => 121.0
    (mins-secs-to-secs '(16 59 534)))
    => 1019.534
    (mins-secs-to-secs "3:06.829"))
    => 186.829
    ;; using a different separator character between minutes and seconds
    (mins-secs-to-secs "3-36.29" #\-) 0.0001)
    => 216.29

SYNOPSIS

    (defun mins-secs-to-secs (time &optional (post-mins #\:))

## utilities/move-elements [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DATE

     02-Mar-2011

DESCRIPTION

     Move the specified elements from one list (if they are present in that
     list) to another, deleting them from the first.

ARGUMENTS

     - A list of elements that are the elements to be moved.
     - A list from which the specified elements are to be moved and deleted.
     - A list to which the specified elements are to be moved.

OPTIONAL ARGUMENTS

     - A predicate by which to test that the specified elements are equal to
       elements of the source list. Default = #'eq.

RETURN VALUE

     Two values: A first list that is the source list after the items have been
     moved; a second list that is the target list after the items have been
     moved.

EXAMPLE

    (move-elements '(3 5 8) '(1 2 3 4 5 6 7 8 9) '(a b c d e))

    => (1 2 4 6 7 9), (8 5 3 A B C D E)

SYNOPSIS

    (defun move-elements (what from to &optional (test #'eq))

## utilities/move-to-end [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DATE

     22-May-2011

DESCRIPTION

     Move a specified element of a given list to the end of the list, returning
     the new list.

     NB: If the element exists more than once in the given list, all but one of
         the occurrences will be removed and only one of them will be placed at
         the end.

ARGUMENTS

     - An item that is an element of the list that is the second argument.
     - A list.

RETURN VALUE

     A list.

EXAMPLE

    ;;; All unique items
    (move-to-end 2 '(1 2 3 4 5))

    => (1 3 4 5 2)

    ;;; Duplicate items
    (move-to-end 2 '(1 2 3 2 4 2 5))

    => (1 3 4 5 2)

SYNOPSIS

    (defun move-to-end (what list &optional (test #'eql))

## utilities/nconc-sublists [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DESCRIPTION

     Concatenate corresponding sublists of a given list. Each sublist in the
     argument should have the same length and number of sublists etc.

ARGUMENTS

     A list of lists.

RETURN VALUE

     A list of lists.

EXAMPLE

    (nconc-sublists '(((1 2) (a b) (cat dog))
                      ((3 4) (c d) (bird fish))
                      ((5 6) (e f) (pig cow))))

    => ((1 2 3 4 5 6) (A B C D E F) (CAT DOG BIRD FISH PIG COW))

SYNOPSIS

    (defun nconc-sublists (lists)

## utilities/nearest [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DATE

     15th May 2020, Heidhausen

DESCRIPTION

     Return the nearest number in a list to the first argument

ARGUMENTS

     - the number we're looking to get the closest to
     - the list of numbers we'll search

RETURN VALUE

     the element of the list that's closest to the first argument, the list
     sorted by nearest to the number, the distances to the number for the sorted
     list.

OPTIONAL ARGUMENTS

     none

EXAMPLE

    (nearest 1.21 '(4 2 5 3 5 4 1.2 1.3 1.1999))
    --> 1.2

SYNOPSIS

    (defun nearest (num list)

## utilities/nearest-power-of-2 [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DESCRIPTION

     Return the closest number to the specified value that is a power of two but
     not greater than the specified value (unless the optional argument is T:
     see below).

ARGUMENTS

     - A number.

OPTIONAL ARGUMENTS

     - T or NIL to indicate whether we can return a power of 2 greater than the
       argument, if that is nearer to the argument than the lower power or 2.

RETURN VALUE

     An integer that is a power of two.

EXAMPLE

    (nearest-power-of-2 31)

    => 16

    (nearest-power-of-2 31 t)

    => 32

    (nearest-power-of-2 32)

    => 32

    (nearest-power-of-2 33)

    => 32

SYNOPSIS

    (defun nearest-power-of-2 (num &optional allow>)

## utilities/now-string [ Functions ]

[ Top ] [ utilities ] [ Functions ]

AUTHOR

     Daniel Ross (mr.danielross[at]gmail[dot]com)

DATE

     Sat 28 Mar 2020 13:21:08 GMT - London

DESCRIPTION

     Return a string representing the current time in the format:
     YEAR MONTH DAY - HOURS MINUTES SECONDS
     e.g. "20200328-132227"

     It is thought that this function might be useful when outputing multiple
     files during the test phase of a piece. E.g.
     (cmn-display +mini+
                  :file (concatenate 'string "my-piece" (now-string) ".eps"))

ARGUMENTS

     None

OPTIONAL ARGUMENTS

     None

RETURN VALUE

     A string

EXAMPLE

    (now-string)

    => "20200328-132227"

    (concatenate 'string "my-piece_" (now-string) ".eps")

    => "my-piece_20200328-133357.eps"

SYNOPSIS

    (defun now-string ()

## utilities/octave-freqs [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DESCRIPTION

     A boolean test to determine whether two specified frequencies are octave
     transpositions of the same pitch class.

ARGUMENTS

     - A first number that is a frequency in Hertz.
     - A second number that is a frequency in Hertz.

OPTIONAL ARGUMENTS

     - T or NIL to indicate whether identical frequencies ("unison") are also
       to be considered octave transpositions of the same pitch class.
       T = unisons are also octaves. Default = T.

RETURN VALUE

     T or NIL.

EXAMPLE

    (octave-freqs 261.63 2093.04)

    => T

    (octave-freqs 261.63 3000.00)

    => NIL

    (octave-freqs 261.63 261.63)

    => T

    (octave-freqs 261.63 261.63 nil)

    => NIL

SYNOPSIS

    (defun octave-freqs (freq1 freq2 &optional (unison-also t))

## utilities/one-to-many [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DATE

     June 23rd 2020

DESCRIPTION

     Find a one-to-many relationship between the first argument and a number of
     equally-spaced points given in the second argument. The first argument is a
     number between 0.0 and 1.0 (inclusive). We calculate the proximities from
     this point to the number of points given and return them as a list,
     optionally raised to a given exponent. The list returned is scaled so that
     all values sum to 1.0, so this is particularly useful for, say, calculating
     a number of amplitude scalers for a multi-voice synthesis process.

ARGUMENTS

     - the point: a number between 0.0 and 1.0 inclusive
     - the number of points to use in the calculation. This will also be the
       number of results returned. Alternatively this can be a list of numbers
       between 0.0 and 1.0. This way you can pass your own points for e.g. an
       unequally-spaced set. In this case though the proximity is still
       determined from a maximum of 1.0, not the highest number in the given
       list.

OPTIONAL ARGUMENTS

     - the exponent to raise proximities to. 1.0 will return a linear
       relationship. > 1.0 will exaggerate the relationships so that those points
       further away from the first argument will be pushed further away than a
       linear relationship. < 1.0 will lessen the distances.

RETURN VALUE

     a list of numbers the length of which is the same as the 2nd argument and
     the sum of which is 1.0

EXAMPLE

    (one-to-many .8 7) -->
    (0.045112778 0.082706764 0.12030074 0.15789473 0.19548872 0.21804512 0.18045112)
    (one-to-many .8 7 .7) -->
    (0.06509622 0.09950039 0.1293403 0.15646003 0.18169008 0.19612299 0.17178996)
    (one-to-many .8 7 1.3)  -->
    (0.030845987 0.06782856 0.11039718 0.15721251 0.20752355 0.23917702 0.1870151)
    ;;; passing 5 points: these don't have to have min/max of 0 and 1 ...
    (one-to-many .8 '(0 .1 .35 .7 .92)) -->
    (0.07067137 0.10600708 0.19434628 0.3180212 0.31095406)
    ;;; ... and they don't have to be in ascending order either
    (one-to-many .8 '(0 .1 .35 .7 .2)) -->
    (0.08510638 0.12765959 0.23404254 0.38297874 0.17021276)

SYNOPSIS

    (defun one-to-many (one how-many &optional (expt 1.0))

## utilities/parse-audacity-label-file [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DATE

     August 12th 2019

DESCRIPTION

     Parse a labels file exported from Audacity and return a list of (start end
     label) triplets. Times are in seconds.

ARGUMENTS

     - the path to the label file

RETURN VALUE

     a list

SYNOPSIS

    (defun parse-audacity-label-file (label-file)

## utilities/parse-audacity-label-file-for-loops [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DESCRIPTION

     Read an audacity label file and return its loop points as groups.

     NB: If this fails it's probably because there's a tab between time and
         label instead of spaces: save in emacs to detab.

     NB: Beware that marker files created on different operating systems from
         the one on which this function is called might trigger errors due to
         newline character mismatches.

ARGUMENTS

     - A string that is the name of the label file to be parsed, including
       directory path and extension.

RETURN VALUE

     Returns a list of lists which are the grouped time points.

     Also prints separate feedback to the listener.

EXAMPLE

    (parse-audacity-label-file-for-loops  "/path/to/24-7loops1.txt")

    =>
    313 markers, 50 loops read

    ((25.674559 25.829296 26.116327 26.649048 27.038843)
     (32.211884 32.33669 32.481815 32.618233 32.716915 32.902676 33.227757
      33.61959)
     (36.893604 37.059048 37.160633 37.27383 37.439274 37.4683 37.627937)
     (39.52907 39.81932 39.999275 40.2634 40.338867 40.605896)
     (45.612698 45.818775 46.050976 46.145306 46.275192)
     (46.4566 46.644535 46.76934 46.886894 46.971066 47.16553)
     (84.15927 84.260864 84.292786 84.355194 84.47274 84.52789 84.556915
      84.65415)
     ...
     (676.1075 676.79114 677.1503 677.57904 678.12366)
     (799.29205 799.8019 800.58984 800.96063 801.13446 801.45886)
     (804.98145 805.2016 805.5724 805.83887 806.31396))

SYNOPSIS

    (defun parse-audacity-label-file-for-loops (label-file)

## utilities/parse-wavelab-marker-file-for-loops [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DESCRIPTION

     Read a wavelab marker file and return its loop points as groups.

     The marker file must contain markers with the word "loop". A marker with
     that name will start a new set of loop points, and nameless markers will
     belong to the group until the next "loop" marker.

ARGUMENTS

     - A string that is the name of the marker file to be parsed, including
       directory path and extension.

OPTIONAL ARGUMENTS

     keyword arguments:
     - :sampling-rate. An integer that is the sampling rate of the sound file to
       which the marker file refers. This value will affect the resulting time
       points. Default = 44100.
     - :max-length. The maximum duration in seconds between two points: anything
       greater than this will result in a warning being printed.

RETURN VALUE

     Returns a list of lists which are the grouped time points.

     Also prints separate feedback to the listener.

EXAMPLE

    (parse-wavelab-marker-file-for-loops "/path/to/24-7loops1.mrk")

    =>
    WARNING:
       utilities::parse-wavelab-marker-file-for-loops
       loop points 10:13.213 to 10:14.475 are too long (1.2620239)
    WARNING:
       utilities::parse-wavelab-marker-file-for-loops
       loop points 10:33.223 to 10:34.486 are too long (1.2630615)
    WARNING:
       utilities::parse-wavelab-marker-file-for-loops
       loop points 10:36.456 to 10:37.522 are too long (1.06604)

    312 markers, 50 loops read

    ((25.674559 25.829296 26.116327 26.649048 27.038843)
     (32.211884 32.33669 32.481815 32.618233 32.716915 32.902676 33.227757
      33.61959)
     (36.893604 37.059048 37.160633 37.27383 37.439274 37.4683 37.627937)
     (39.52907 39.81932 39.999275 40.2634 40.338867 40.605896)
     (45.612698 45.818775 46.050976 46.145306 46.275192)
     (46.4566 46.644535 46.76934 46.886894 46.971066 47.16553)
     (84.15927 84.260864 84.292786 84.355194 84.47274 84.52789 84.556915
      84.65415)
     ...
     (655.91077 656.4554 656.80304 657.4519 658.04285 658.8192)
     (676.1075 676.79114 677.1503 677.57904 678.12366)
     (799.29205 799.8019 800.58984 800.96063 801.13446 801.45886)
     (804.98145 805.2016 805.5724 805.83887 806.31396))

SYNOPSIS

    (defun parse-wavelab-marker-file-for-loops
        (marker-file &key (sampling-rate 44100) (max-length 1.0))

## utilities/partial-freqs [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DATE

     13-Dec-2011

DESCRIPTION

     A Boolean test to determine whether either of two specified frequencies
     can be considered a harmonic partial of the other.

ARGUMENTS

     - A first frequency in Hertz.
     - A second frequency in Hertz.

OPTIONAL ARGUMENTS

     - T or NIL to indicate whether identical frequencies ("unison") are also to
       be considered partials of each other. T = unison are partials.
       Default = T.

RETURN VALUE

     T if one of the frequencies has the ratio of a harmonic partial to the
     other, otherwise NIL.

EXAMPLE

    (partial-freqs 300 900)

    => T

    (partial-freqs 300 700)

    => NIL

    (partial-freqs 300 300)

    => T

    (partial-freqs 300 300 nil)

    => NIL

SYNOPSIS

    (defun partial-freqs (freq1 freq2 &optional (unison-also t))

## utilities/pdivide [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DESCRIPTION

     Creates a list of proportionally related times, dividing a starting
     duration into a number of smaller durations a specified number of times.
     We start with a proportion as a ratio (e.g. 3/2) and divide the given
     duration into two parts according to that ratio.  Then those two parts will
     be divided into the same ratios.  This will iterate the number of times
     indicated by the second argument.

     The following are some classical proportions:
             Latin        (Greek)
     (3 : 2) Sesquialtera (Diapente)
     (4 : 3) Sesquitertia (Diatessaron)
     (5 : 4) Sesquiquarta (Diatonus Semitonus)
     (8 : 3) Duplasuperbipartiens (Diapson Diatesseron)
     (9 : 8) Sesquioctava (Tonus)

ARGUMENTS

     - an integer or ratio (in Lisp terms, a rational) e.g. 3/2
     - an integer >=1 specifying the number of times to iterate the process of
       dividing the duration into proportions.

OPTIONAL ARGUMENTS

     keyword arguments:
     - :duration. The overall duration to apply the proportional divisions to.
       Units are arbitrary of course as this is just a number. Default 1.0.
     - :print. If T, print each level of division as we proceed. Default NIL.
     - :reverse. If T reverse the proportion (so 3/2 becomes 2/3). Default NIL.
     - :alternate. If T, reverse the proportion every other division (not
       iteration) so that if we have a proportion of 3/2 on the second iteration
       we divide into 3/2 then 2/3.  Default NIL.
     - :increment. If T, then each time we divide we increment both sides of the
       proportion,  so 3:2 becomes 4:3 which becomes 5:4 etc.  Default NIL.
     - :halves. This will only make a difference if :increment is T: As results
       tend overall towards increasing (when numerator < denominator e.g. 2/3) or
       decreasing (numerator > denominator e.g. 3/2) numbers, we can mix things
       up by dividing the resultant list into two halves and splicing their
       elements one after the other.  Default NIL.
     - :shuffle. Mix things up by shuffling the resultant list.  As this uses
       the shuffle algorithm we have fixed-seed randomness so results will be
       the same upon each call within the same Lisp implementation/version.
       Default NIL.

RETURN VALUE

     Three values: the list of ascending timings from the last generation of the
     calculated proportions; the durations of each part for the last generation;
     the list of ascending timings for _each_ generation of the calculated
     proportions (a list of lists).

EXAMPLE

    Notice here that each generation prints the proportions along with the
    durations these correspond to and the start time of each (cumulative durations).

    (pdivide 3/2 4 :duration 35 :print t)

    PRINTS:
    Generation 1: 3 (21.00=21.00), 2 (14.00=35.00),

    Generation 2: 3 (12.60=12.60), 2 (8.40=21.00), 3 (8.40=29.40), 2 (5.60=35.00),

    Generation 3: 3 (7.56=7.56), 2 (5.04=12.60), 3 (5.04=17.64), 2 (3.36=21.00),
    3 (5.04=26.04), 2 (3.36=29.40), 3 (3.36=32.76), 2 (2.24=35.00),

    Generation 4: 3 (4.54=4.54), 2 (3.02=7.56), 3 (3.02=10.58), 2 (2.02=12.60),
    3 (3.02=15.62), 2 (2.02=17.64), 3 (2.02=19.66), 2 (1.34=21.00), 3 (3.02=24.02),
    2 (2.02=26.04), 3 (2.02=28.06), 2 (1.34=29.40), 3 (2.02=31.42), 2 (1.34=32.76),
    3 (1.34=34.10), 2 (0.90=35.00),

    RETURNS:
    (0.0 4.5360003 7.5600004 10.584001 12.6 15.624001 17.640001 19.656002 21.000002
     24.024002 26.040003 28.056004 29.400003 31.416004 32.760006 34.104008
     35.000008)
    (4.5360003 3.0240002 3.0240004 2.0160003 3.0240004 2.0160003 2.0160003
     1.3440002 3.0240004 2.0160003 2.0160003 1.3440002 2.0160003 1.3440001
     1.3440001 0.896)
    ((0.0 4.5360003 7.5600004 10.584001 12.6 15.624001 17.640001 19.656002
      21.000002 24.024002 26.040003 28.056004 29.400003 31.416004 32.760006
      34.104008 35.000008)
     (0.0 7.5600004 12.6 17.640001 21.000002 26.040003 29.400003 32.760002
      35.000004)
     (0.0 12.6 21.0 29.400002 35.0) (0.0 21.0 35.0))

    (pdivide 3/2 4 :duration 35 :print t :increment t :halves t)

    PRINTS:
    Generation 1: 3 (21.00=21.00), 2 (14.00=35.00),

    Generation 2: 4 (12.00=12.00), 3 (9.00=21.00), 5 (7.78=28.78), 4 (6.22=35.00),

    Generation 3: 6 (6.55=6.55), 5 (5.45=12.00), 7 (4.85=16.85), 6 (4.15=21.00),
    8 (4.15=25.15), 7 (3.63=28.78), 9 (3.29=32.07), 8 (2.93=35.00),

    Generation 4: 10 (3.44=3.44), 9 (3.10=6.55), 11 (2.86=9.40), 10 (2.60=12.00),
    12 (2.53=14.53), 11 (2.32=16.85), 13 (2.16=19.01), 12 (1.99=21.00),
    14 (2.15=23.15), 13 (2.00=25.15), 15 (1.88=27.03), 14 (1.75=28.78),
    16 (1.70=30.48), 15 (1.59=32.07), 17 (1.51=33.58), 16 (1.42=35.00),

    RETURNS:
    (0.0 3.4449766 5.595868 8.696347 10.6936035 13.550747 15.428142 18.025545
     19.77778 22.30621 24.0064 26.324125 27.918053 30.078053 31.58647 33.580315
     35.0)
    (3.4449766 2.1508918 3.100479 1.9972568 2.8571434 1.8773947 2.5974028 1.752235
     2.5284283 1.7001898 2.317726 1.593928 2.16 1.5084175 1.9938462 1.4196872)
    ((0.0 3.4449766 6.5454555 9.402599 12.000002 14.52843 16.846155 19.006155
      21.000002 23.150894 25.148151 27.025547 28.777782 30.477972 32.0719 33.58032
      35.000004)
     (0.0 6.5454555 12.000002 16.846157 21.000004 25.148151 28.77778 32.0719
      35.000004)
     (0.0 12.000001 21.0 28.777779 35.0) (0.0 21.0 35.0))

SYNOPSIS

    (defun pdivide (start levels &key (duration 1.0) print reverse alternate
                        halves shuffle increment)

## utilities/pexpand [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DESCRIPTION

     Instead of dividing an overall duration (pdivide) we start with a
     proportion and expand outwards from there, keeping each newly created part
     in the same proportion.  This is repeated the number of times specified in
     the first argument.  Useful for generating maps (section structure).

ARGUMENTS

     The number of times to expand proportionally.

OPTIONAL ARGUMENTS

     As many integer proportions as required.  If the last argument here is t,
     then instead of using letters to denote sections we use numbers instead.

RETURN VALUE

     3 values:
     1) a list showing the cumulative count (e.g. bar numbers) of where major
     and minor sections occur.  Topmost sections will have the labels A, B, C,
     etc. with subsections such as A.A, A.B, ... C.C.C.C.  Of course, wherever a
     major section starts, an arbitrary number of subsections also begin, but
     only the most major section is present in the list.
     2) the structure of the sections and subsections in the form of a list of
     sublists for each, and containing the section labels paired with their
     length.  The bottommost subsection will have a length of the sum of the
     proportions, with higher subsection groupings showing multiples of this.
     3) the overall length of the structure produced (also the first element of
     the second returned value).

EXAMPLE

    ;;; 2 generations:
    (pexpand 2 3 2) =>
    (1 (A) 6 (A A A B) 11 (A A A C) 16 (A A B) 21 (A A B B) 26 (A B) 31 (A B A B)
     36 (A B A C) 41 (A B B) 46 (A B B B) 51 (A C) 56 (A C A B) 61 (A C A C) 66
     (A C B) 71 (A C B B) 76 (B) 81 (B A A B) 86 (B A A C) 91 (B A B) 96 (B A B B)
     101 (B B) 106 (B B A B) 111 (B B A C) 116 (B B B) 121 (B B B B))
    (125
     (((A) 75)
      (((A A) 25) (((A A A) 15) ((A A A A) 5) ((A A A B) 5) ((A A A C) 5))
       (((A A B) 10) ((A A B A) 5) ((A A B B) 5)))
      (((A B) 25) (((A B A) 15) ((A B A A) 5) ((A B A B) 5) ((A B A C) 5))
       (((A B B) 10) ((A B B A) 5) ((A B B B) 5)))
      (((A C) 25) (((A C A) 15) ((A C A A) 5) ((A C A B) 5) ((A C A C) 5))
       (((A C B) 10) ((A C B A) 5) ((A C B B) 5))))
     (((B) 50)
      (((B A) 25) (((B A A) 15) ((B A A A) 5) ((B A A B) 5) ((B A A C) 5))
       (((B A B) 10) ((B A B A) 5) ((B A B B) 5)))
      (((B B) 25) (((B B A) 15) ((B B A A) 5) ((B B A B) 5) ((B B A C) 5))
       (((B B B) 10) ((B B B A) 5) ((B B B B) 5)))))
    125

    ;;; 3 generations:
    (pexpand 3 3 2) =>
    (1 (A) 6 (A A A A A B) 11 (A A A A A C) 16 (A A A A B) 21 (A A A A B B) 26
     (A A A B) 31 (A A A B A B) 36 (A A A B A C) 41 (A A A B B) 46 (A A A B B B) 51
     (A A A C) 56 (A A A C A B) 61 (A A A C A C) 66 (A A A C B) 71 (A A A C B B) 76
    ...
     581 (B B B A A B) 586 (B B B A A C) 591 (B B B A B) 596 (B B B A B B) 601
     (B B B B) 606 (B B B B A B) 611 (B B B B A C) 616 (B B B B B) 621
     (B B B B B B))
    (625
     (((A) 375)
      (((A A) 125)
       (((A A A) 75)
        (((A A A A) 25)
         (((A A A A A) 15) ((A A A A A A) 5) ((A A A A A B) 5) ((A A A A A C) 5))
         (((A A A A B) 10) ((A A A A B A) 5) ((A A A A B B) 5)))
    ...
       (((B B B) 50)
        (((B B B A) 25)
         (((B B B A A) 15) ((B B B A A A) 5) ((B B B A A B) 5) ((B B B A A C) 5))
         (((B B B A B) 10) ((B B B A B A) 5) ((B B B A B B) 5)))
        (((B B B B) 25)
         (((B B B B A) 15) ((B B B B A A) 5) ((B B B B A B) 5) ((B B B B A C) 5))
         (((B B B B B) 10) ((B B B B B A) 5) ((B B B B B B) 5)))))))
    625

    ;;; 2 generations of 3 proportional values, returning numbers for labels
    (pexpand 2 3 2 4 t) =>
    (1 (1) 10 (1 1 1 2) 19 (1 1 1 3) 28 (1 1 2) 37 (1 1 2 2) 46 (1 1 3) 55
     (1 1 3 2) 64 (1 1 3 3) 73 (1 1 3 4) 82 (1 2) 91 (1 2 1 2) 100 (1 2 1 3) 109
     (1 2 2) 118 (1 2 2 2) 127 (1 2 3) 136 (1 2 3 2) 145 (1 2 3 3) 154 (1 2 3 4)
    ... (3 4 2 2) 694 (3 4 3) 703 (3 4 3 2) 712 (3 4 3 3) 721 (3 4 3 4))

    (729
     (((1) 243)
      (((1 1) 81) (((1 1 1) 27) ((1 1 1 1) 9) ((1 1 1 2) 9) ((1 1 1 3) 9))
       (((1 1 2) 18) ((1 1 2 1) 9) ((1 1 2 2) 9))
       (((1 1 3) 36) ((1 1 3 1) 9) ((1 1 3 2) 9) ((1 1 3 3) 9) ((1 1 3 4) 9)))
    ...
       (((3 2 2) 18) ((3 2 2 1) 9) ((3 2 2 2) 9))
       (((3 2 3) 36) ((3 2 3 1) 9) ((3 2 3 2) 9) ((3 2 3 3) 9) ((3 2 3 4) 9)))
      (((3 3) 81) (((3 3 1) 27) ((3 3 1 1) 9) ((3 3 1 2) 9) ((3 3 1 3) 9))
       (((3 3 2) 18) ((3 3 2 1) 9) ((3 3 2 2) 9))
       (((3 3 3) 36) ((3 3 3 1) 9) ((3 3 3 2) 9) ((3 3 3 3) 9) ((3 3 3 4) 9)))
      (((3 4) 81) (((3 4 1) 27) ((3 4 1 1) 9) ((3 4 1 2) 9) ((3 4 1 3) 9))
       (((3 4 2) 18) ((3 4 2 1) 9) ((3 4 2 2) 9))
       (((3 4 3) 36) ((3 4 3 1) 9) ((3 4 3 2) 9) ((3 4 3 3) 9) ((3 4 3 4) 9)))))
    729

SYNOPSIS

    (defun pexpand (generations &rest proportions)

## utilities/pexpand-find [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DESCRIPTION

     Find the cumulative number of where a label occurs in a list returned by
     pexpand.

ARGUMENTS

     - the label we're looking for
     - a list of the type returned by pexpand (first returned value).

OPTIONAL ARGUMENTS

     - a function to be called when the label cannot be found.  Default =
     #'error but could also be #'warn or NIL.

RETURN VALUE

     An integer.

SYNOPSIS

    (defun pexpand-find (label list &optional (on-error #'error))

## utilities/pexpand-section-length [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DESCRIPTION

     Return the length (integer) of any arbitrary section in the data returned
     by pexpand.

ARGUMENTS

     - The (rest of) the kind of list returned as the second value of a call to
       pexpand.
     - The section ID we want the length of, either as a list or single symbol.

RETURN VALUE

     An integer or NIL if the section can't be found.

EXAMPLE

    (pexpand-section-length (rest (nth-value 1 (pexpand 2 3 6 4 5))) '(c a b))
    => 108

    (pexpand-section-length (rest (nth-value 1 (pexpand 2 3 6 4 5))) 'c)
    => 1296

SYNOPSIS

    (defun pexpand-section-length (pexpand-list section)

## utilities/power-of-2 [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DESCRIPTION

     Test whether the specified number is a power of two and return the
     logarithm of the specified number to base 2.

     This method returns two values: T or NIL for the test and a decimal that is
     the logarithm of the specified number to base 2.

ARGUMENTS

     - A number.

RETURN VALUE

     Two values: T or NIL for the test and a decimal number that is the
     logarithm of the specified number to base 2.

EXAMPLE

    (power-of-2 16)

    => T, 4.0

    (power-of-2 17.3)

    => NIL, 4.1127

SYNOPSIS

    (defun power-of-2 (float)

## utilities/prime [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DATE

     August 5th 2019, Heidhausen

DESCRIPTION

     Taken from dlocsig.lisp by Fernando Lopez Lezcano (in the CLM package):
     Return T or NIL to indicated whether the argument is a prime number or not.

ARGUMENTS

     an integer (all other types, including floats, will trigger an error)

RETURN VALUE

     T or NIL

SYNOPSIS

    (defun prime (val)

## utilities/pts2cm [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DESCRIPTION

     Convert a specified number of points to a length in centimeters at a
     resolution of 72ppi.

ARGUMENTS

     - A number.

RETURN VALUE

     A number.

EXAMPLE

    (pts2cm 150)

    => 5.2916665

SYNOPSIS

    (defun pts2cm (points)

## utilities/random-amount [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DESCRIPTION

     Return a random number from within a total range of <percent> of the given
     number, centering around zero. Thus, if the <number> is 100, and the
     <percent> is 5, the results will be a random number between -2.5 and +2.5.

ARGUMENTS

     A number.

OPTIONAL ARGUMENTS

     A number that will be a percent of the given number.

RETURN VALUE

     A random positive or negative number.

EXAMPLE

    ;;; Using the default will return numbers within a 5% span of the given number,
    ;;; centering around zero. With 100 that means between -2.5 and +2.5.
    (loop repeat 10 collect (random-amount 100))

    => (0.7424975 -1.4954442 -1.7126495 1.5918689 -0.43478793 -1.7916341 -1.9115914
        0.8541988 0.057197176 2.0713913)

    ;;; Specifying 10% of 80 will return random numbers between -4.0 and +4.0
    (loop repeat 10 collect (random-amount 80 10))

    => (-0.66686153 3.0387697 3.4737322 -2.3753185 -0.8495751 -0.47580242
        -0.25743783 -1.1395472 1.3560238 -0.5958566)

SYNOPSIS

    (defun random-amount (number &optional (percent 5))

## utilities/random-from-list [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DESCRIPTION

     Return a random element from a specified list of elements.

ARGUMENTS

     - A list.

OPTIONAL ARGUMENTS

     - An integer can be passed stating the length of the list, for more
       efficient processing. NB: There is no check to ensure this number is
       indeed the length of the list. If the number is less than the length of
       the list, only elements from the first part of the list will be
       returned. If it is greater than the length of the list, the method may
       return NIL.

RETURN VALUE

     An element from the specified list.

EXAMPLE

    (random-from-list '(3 5 7 11 13 17 19 23 29))

    => 13

SYNOPSIS

    (defun random-from-list (list &optional list-length) ; for efficiency

## utilities/randomise [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DESCRIPTION

     Return a random decimal number close to (+ or -) the number specified
     (within a certain percentage of that number's value). Note that if you want
     the result to go from 0 to 2x the argument, then <percent> needs to be 200,
     not 100.

ARGUMENTS

     - A number.

OPTIONAL ARGUMENTS

     - A number that is a percentage value, such that any random number returned
       will be within that percentage of the original number's value.
       Default = 5.

RETURN VALUE

     A decimal number.

EXAMPLE

    (loop repeat 10 collect (randomise 100))

    => (99.413795 99.15346 98.682014 100.76199 97.74929 99.05693 100.59494 97.96452
        100.42091 100.01329)

SYNOPSIS

    (defun randomise (number &optional (percent 5))

## utilities/read-from-file [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DESCRIPTION

     Read a Lisp expression from a file. This is determined by the Lisp
     parenthetical syntax.

ARGUMENTS

     - A string that is a file name including directory path and extension.

RETURN VALUE

     The Lisp expression contained in the file.

EXAMPLE

    (read-from-file "/path/to/lisp-lorem-ipsum.txt")

    => (LOREM IPSUM DOLOR SIT AMET CONSECTETUR ADIPISCING ELIT CRAS CONSEQUAT
        CONVALLIS JUSTO VITAE CONSECTETUR MAURIS IN NIBH VEL EST TEMPUS LOBORTIS
        SUSPENDISSE POTENTI SED MAURIS MASSA ADIPISCING VITAE DIGNISSIM CONDIMENTUM
        VOLUTPAT VEL FELIS FUSCE AUGUE DUI PULVINAR ULTRICIES IMPERDIET SED
        PHARETRA EU QUAM INTEGER IN VULPUTATE VELIT ALIQUAM ERAT VOLUTPAT VIVAMUS
        SIT AMET ORCI EGET EROS CONSEQUAT TINCIDUNT NUNC ELEMENTUM ADIPISCING
        LOBORTIS MORBI AT LOREM EST EGET MATTIS ERAT DONEC AC RISUS A DUI MALESUADA
        LOBORTIS AC AT EST INTEGER AT INTERDUM TORTOR VIVAMUS HENDRERIT CONSEQUAT
        AUGUE QUISQUE ALIQUAM TELLUS NEC VESTIBULUM LOBORTIS RISUS TURPIS LUCTUS
        LIGULA IN BIBENDUM FELIS SEM PULVINAR DOLOR VIVAMUS RHONCUS NISI GRAVIDA
        PORTA VULPUTATE IPSUM LACUS PORTA RISUS A VULPUTATE MAGNA JUSTO A EST)

SYNOPSIS

    (defun read-from-file (file)

## utilities/reflect-list [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DESCRIPTION

     Order a list of numbers from least to greatest, then transpose the list so
     that if an element is the second lowest, it will be replaced by the second
     highest etc.

ARGUMENTS

     - A list or numbers.

RETURN VALUE

     A list of numbers.

EXAMPLE

    (reflect-list '(1 4 3 5 9 6 2 7 8 8 9))

    => (9 6 7 5 1 4 8 3 2 2 1)

SYNOPSIS

    (defun reflect-list (list)

## utilities/remove-all [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DESCRIPTION

     Remove all of the specified elements from a list, returning a list
     containing only those elements that are not in the first argument list.

ARGUMENTS

     - A first list that is the list of items to remove.
     - A second list that is the original list.

OPTIONAL ARGUMENTS

     - A predicate for testing equality between the elements of the two lists.
       Default = #'eq.

RETURN VALUE

     A list.

EXAMPLE

    (remove-all '(3 5 8 13) '(1 2 3 4 5 6 7 8 9 10 11 12 13))

    => (1 2 4 6 7 9 10 11 12)

SYNOPSIS

    (defun remove-all (rm-list list &optional (test #' eq))

## utilities/remove-elements [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DESCRIPTION

     Remove a specified number of elements from a given list starting at a
     specified position (0-based) within the list.

ARGUMENTS

     - A list.
     - An integer that is the 0-based position within that list that will be the
       first element to be removed.
     - An integer that is the number of elements to remove.

RETURN VALUE

     A list.

EXAMPLE

    (remove-elements '(1 2 3 4 5 6 7) 2 4)

    => (1 2 7)

SYNOPSIS

    (defun remove-elements (list start how-many)

## utilities/remove-more [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DESCRIPTION

     Remove all instances of a list of specified elements from an original
     list. The predicate used to test the presence of the specified elements in
     the original list must be specified by the user (such as #'eq, #'equalp,
     #'= etc.)

ARGUMENTS

     - A list.
     - A predicate with which to test the presence of the specified elements.
     - A sequence of elements to be removed from the given list.

RETURN VALUE

     A list.

EXAMPLE

    (remove-more '(1 2 3 4 5 5 5 6 7 7 8) #'= 5 7 2)

    => (1 3 4 6 8)

SYNOPSIS

    (defun remove-more (list test &rest remove)

## utilities/replace-elements [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DESCRIPTION

     Replace the elements in list between start and end (inclusive) with the new
     list.

ARGUMENTS

     - A list.
     - An integer that is first position of the segment of the original list to
       be replaced.
     - An integer that is the last position of the segment of the original list
       to be replaced.
     - A list that is to replace the specified segment of the original
       list. This list can be of a different length than that of the segment
       of the original specified by the start and end positions.

RETURN VALUE

     A list.

EXAMPLE

    (replace-elements '(1 2 3 4 5 6 7 8 9) 3 7 '(dog cat goldfish))

    => (1 2 3 DOG CAT GOLDFISH 9)

SYNOPSIS

    (defun replace-elements (list start end new)

## utilities/rescale [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DATE

     June 8th 2016, Edinburgh

DESCRIPTION

     Given a value within an original range, return its value withing a new range

ARGUMENTS

     - the value we want to rescale
     - the original minimum
     - the original maximum
     - the new minimum
     - the new maximum

OPTIONAL ARGUMENTS

     keyword arguments:
     :out-of-range. The function to call when the first argument is not within
     the range of arguments two and three. This would normally be #'error,
     #'warn or NIL. If #'warn or NIL, argument 1 will be hard-limited to the
     original range. Default = #'error

RETURN VALUE

     The value within the new range (a number)

EXAMPLE

    (rescale .5 0 1 0 100)
    ==> 50.0

SYNOPSIS

    (defun rescale (val min max new-min new-max &optional (out-of-range #'error))

## utilities/round-if-close [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DESCRIPTION

     Round a decimal number if it is within a given tolerance to the next whole
     number.

ARGUMENTS

     - A decimal number.

OPTIONAL ARGUMENTS

     - If the given number is this amount or less than the nearest whole number,
       round the given number to the nearest whole number.

RETURN VALUE

     If the given number is within the tolerance, return the number, otherwise
     return the nearest whole number.

EXAMPLE

    (round-if-close 1.999998)

    => 1.999998

    (round-if-close 1.999999)

    => 2

SYNOPSIS

    (defun round-if-close (num &optional (tolerance 0.000001))

## utilities/scale-env [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DESCRIPTION

     Scale either the x-axis values, the data values, or both of a list of
     break-point pairs by specified factors.

ARGUMENTS

     - An envelope in the form of a list of break-point pairs.
     - A number that is the factor by which the y values (data segment of the
       break-point pairs) are to be scaled.

OPTIONAL ARGUMENTS

     keyword arguments:
     - :y-min. A number that is the minimum value for all y values after
       scaling.  NB The -min/-max arguments are hard-limits only; they do not
       factor into the arithmetic.
     - :y-max. A number that is the maximum value for all y values after
       scaling.
     - :x-scaler. A number that is the factor by which to scale the x-axis
       values of the break-point pairs.
     - :x-min. A number that is the minimum value for all x values after
       scaling. NB: This optional argument can only be used if a value has been
       specified for the :x-scaler.
     - :x-max. A number that is the maximum value for all x values after
       scaling. NB: This optional argument can only be used if a value has been
       specified for the :x-scaler.

RETURN VALUE

     An envelope in the form of a list of break-point pairs.

EXAMPLE

    ;;; Scaling only the y values.
    (scale-env '(0 53 25 189 50 7 75 200 100 3) 0.5)

    => (0 26.5 25 94.5 50 3.5 75 100.0 100 1.5)

    ;;; Scaling the y values and setting a min and max for those values
    (scale-env '(0 53 25 189 50 7 75 200 100 3) 0.5 :y-min 20 :y-max 100)

    => (0 26.5 25 94.5 50 20 75 100 100 20)

    ;;; Scaling only the x-axis values
    (scale-env '(0 53 25 189 50 7 75 200 100 3) 1.0 :x-scaler 2)

    => (0 53.0 50 189.0 100 7.0 150 200.0 200 3.0)

    ;;; Scaling the x values and setting a min and max for those values
    (scale-env '(0 53 25 189 50 7 75 200 100 3) 1.0 :x-scaler 2 :x-min 9 :x-max 90)

    => (9 53.0 50 189.0 90 7.0 90 200.0 90 3.0)

SYNOPSIS

    (defun scale-env (env y-scaler &key x-scaler
                                        (x-min most-negative-double-float)
                                        (y-min most-negative-double-float)
                                        (x-max most-positive-double-float)
                                        (y-max most-positive-double-float))

## utilities/secs-to-mins-secs [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DESCRIPTION

     Convert a number of seconds into a string of the form "24:41.723" where
     seconds are always rounded to three decimal places (i.e. milliseconds).

ARGUMENTS

     - the number of seconds

OPTIONAL ARGUMENTS

     keyword arguments:
     - :post-mins. The string used to separate minutes and seconds. Default ":"
     - :post-secs. The string used to separate seconds and milliseconds.
        Default "."
     - :post-msecs. The string used to follow milliseconds. Default ""
     - :same-width. Ensure minutes values are always two characters wide, like
       seconds, i.e with a leading 0.
     - :round. Round to the nearest second and don't print milliseconds. Default
       NIL.

RETURN VALUE

     A string

EXAMPLE

    (secs-to-mins-secs 77.1232145)
    "1:17.123"
    (secs-to-mins-secs 67.1)
    "1:07.100"
    (secs-to-mins-secs 67.1 :same-width t)
    "01:07.100"
    (secs-to-mins-secs 67.1 :same-width t :post-secs "s")
    "01:07s100"
    (secs-to-mins-secs 67.1 :post-secs "secs" :post-mins "min" :post-msecs "msecs")
    "1min07secs100msecs"
    (secs-to-mins-secs 67.7 :same-width t :round t)
    "01:08"

SYNOPSIS

    (defun secs-to-mins-secs (seconds &key
                                        round
                                        (post-mins ":")
                                        (post-secs ".")
                                        (post-msecs "")
                                        (same-width nil))

## utilities/semitones [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DESCRIPTION

     Return the sample-rate conversion factor required for transposing an audio
     file by a specific number of semitones. The number of semitones can be
     given as a decimal number, and may be positive or negative.

ARGUMENTS

     - A number of semitones.

OPTIONAL ARGUMENTS

     - A number that is the factor required to transpose by an octave.
       Default = 2.0.
     - A number that is the number of semitones per octave. Default = 12.

RETURN VALUE

     A number.

EXAMPLE

    ;;; Usage with default values
    (semitones 3)

    => 1.1892071

    ;;; Specifying a different number of semitones per octave
    (semitones 3 2.0 13)

    => 1.1734605

    ;;; Specifying a different factor for transposing by an octave
    (semitones 3 4.0)

    => 1.4142135

    ;;; Fractional semitones are allowed
    (semitones 3.72)

    => 1.2397077

    ;;; Negative semitones are also allowed
    (semitones -3.72)

    => 0.80664176

SYNOPSIS

    (defun semitones (st &optional (octave-size 2.0) (divisions-per-octave 12))

## utilities/setf-last [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DESCRIPTION

     Change the last element in a given list to a specified new element.

ARGUMENTS

     - A list.
     - The new last element of that list.

RETURN VALUE

     Returns the new last element.

EXAMPLE

    (let ((l '(1 2 3 4 5)))
      (setf-last l 'dog)
      l)

    => (1 2 3 4 DOG)

SYNOPSIS

    (defmacro setf-last (list new-last)

## utilities/sort-symbol-list [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DESCRIPTION

     Sort a list of symbols alphabetically ascending, case-insensitive.

ARGUMENTS

     A list of symbols.

RETURN VALUE

     The same list of symbols sorted alphabetically ascending, case-insensitive.

EXAMPLE

    (sort-symbol-list '(Lorem ipsum dolor sit amet consectetur adipiscing))

    => (ADIPISCING AMET CONSECTETUR DOLOR IPSUM LOREM SIT)

SYNOPSIS

    (defun sort-symbol-list (list)

## utilities/splice [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DESCRIPTION

     Insert the elements of a first list into a second list beginning at a
     specified index (0-based).

ARGUMENTS

     - A list that contains the elements to be inserted into the second list.
     - A list into which the elements of the first argument are to be inserted.
     - An integer that is the index within the second list where the elements
       are to be inserted.

RETURN VALUE

     - A list.

EXAMPLE

    (splice '(dog cat goldfish) '(1 2 3 4 5 6 7 8 9) 3)

    => (1 2 3 DOG CAT GOLDFISH 4 5 6 7 8 9)

SYNOPSIS

    (defun splice (elements into-list where)

## utilities/split-groups [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DESCRIPTION

     Create a list consisting of as many repetitions of a specified number as
     will fit into a given greater number, with the last item in the new list
     being the value of any remainder.

ARGUMENTS

     - A number that is to be split into repetitions of a specified smaller
       number (the second argument).
     - The number that is to be the repeating item in the new list. This number
       must be smaller than the first number.

RETURN VALUE

     A list consisting of repetitions of the specified number, with the last
     element being any possible remainder.

EXAMPLE

    (split-groups 101 17)

    => (17 17 17 17 17 16)

SYNOPSIS

    (defun split-groups (num divider)

## utilities/split-into-sub-groups [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DESCRIPTION

     Create a new list consisting of sublists made from the elements of the
     original flat list, whose lengths are determined by the second argument to
     the function.

     NB: The lengths given in the second argument are not required to add up to
         the length of the original list. If their sum is less than the original
         list, the resulting list of sublists will only contain a segment of the
         original elements. If their sum is greater than the length of the
         original list, the last sublist in the new list will be shorter than
         the corresponding group value.

ARGUMENTS

     - A flat list.
     - A list of integers that are the lengths of the consecutive subgroups
       into which the original list is to be divided.

RETURN VALUE

     A list of lists.

EXAMPLE

    ;; Used with a list of subgroup lengths whose sum is equal to the length of the
    ;; original list
    (split-into-sub-groups '(1 2 3 4 5 6 7 8 9 10) '(2 2 3 2 1))

    => ((1 2) (3 4) (5 6 7) (8 9) (10))

    ;; Used with a list of subgroup lengths whose sum is less than the length of the
    ;; original list
    (split-into-sub-groups '(1 2 3 4 5 6 7 8 9 10) '(2 1))

    => ((1 2) (3))

    ;; Used with a list of subgroup lengths whose sum is greater than the length of
    ;; the original list
    (split-into-sub-groups '(1 2 3 4 5 6 7 8 9 10) '(2 3 17))

    => ((1 2) (3 4 5) (6 7 8 9 10))

SYNOPSIS

    (defun split-into-sub-groups (list groups)

## utilities/split-into-sub-groups2 [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DESCRIPTION

     Create a new list of lists by splitting the original flat list into
     sublists of the specified length.

     NB: The length given as the second argument is not required to be fit
         evenly into the length of the original flat list. If the original list
         is not evenly divisible by the specified length, the resulting list of
         sublists will contain a final sublist of a different length.

ARGUMENTS

     - A flat list.
     - An integer that is the length of each of the sublists to be created.

RETURN VALUE

     A list of lists.

EXAMPLE

    ;; The second argument fits evenly into the length of the original list.
    (split-into-sub-groups2 '(1 2 3 4 5 6 7 8 9 10 11 12) 3)

    => ((1 2 3) (4 5 6) (7 8 9) (10 11 12))

    ;; The second argument does not fit evenly into the length of the original
    ;; list.

    (split-into-sub-groups2 '(1 2 3 4 5 6 7 8 9 10 11 12) 5)

    => ((1 2 3 4 5) (6 7 8 9 10) (11 12))

SYNOPSIS

    (defun split-into-sub-groups2 (list length)

## utilities/split-into-sub-groups3 [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DESCRIPTION

     Split a given flat list into sublists of the specified length, putting any
     remaining elements, if there are any, into the last sublist.

ARGUMENTS

     - A flat list.
     - An integer that is the length of the new sublists.

RETURN VALUE

     A list of lists.

EXAMPLE

    (split-into-sub-groups3 '(1 2 3 4 5 6 7 8 9 10 11 12) 3)

    => ((1 2 3) (4 5 6) (7 8 9) (10 11 12))

    (split-into-sub-groups3 '(1 2 3 4 5 6 7 8 9 10 11 12) 5)

    => ((1 2 3 4 5) (6 7 8 9 10 11 12))

SYNOPSIS

    (defun split-into-sub-groups3 (list length)

## utilities/split-into-sub-groups4 [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DATE

     August 28th 2018, Heidhausen

DESCRIPTION

     Split into sub-groups with lengths defined by the integers in the second
     argument list. The difference here to related functions is that the given
     lengths will repeat circularly until no more elements of the first argument
     remain.

ARGUMENTS

     - the list to split into sub-groups
     - a list of lengths, to be repeated

RETURN VALUE

     a list of sublists

EXAMPLE

    (split-into-sub-groups4 '(1 2 3 4 5 6 7 8 9 10 11 12) '(3 4))
    ==> ((1 2 3) (4 5 6 7) (8 9 10) (11 12))

    (split-into-sub-groups4 '(1 2 3 4 5 6 7 8 9 10 11 12 13 14) '(3 4))
    ==> ((1 2 3) (4 5 6 7) (8 9 10) (11 12 13 14))

    (split-into-sub-groups4 '(1 2 3 4 5 6 7 8 9 10 11 12) '(1 2 3 4))
    ==> '((1) (2 3) (4 5 6) (7 8 9 10) (11) (12))

SYNOPSIS

    (defun split-into-sub-groups4 (list lengths)

## utilities/srt [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DESCRIPTION

     Return the semitone transposition for a given sampling rate conversion
     factor.

ARGUMENTS

     - A number that is a sample-rate conversion factor.

OPTIONAL ARGUMENTS

     - A number that is the factor required for transposing one octave.
     - A number that is the number of scale degrees in an octave.

RETURN VALUE

     A number.

EXAMPLE

    ;;; Using the defaults
    (srt 1.73)

    => 9.4893

    ;;; Using a sample-rate conversion factor of 4.0 for the octave and specifying
    ;;; 13 divisions of the octave
    (srt 1.73 4.0 13)

    => 5.14

SYNOPSIS

    (let ((last8vesize 0)
          (log8ve 0.0)) ;; so we don't have to recalculate each time
      (defun srt (srt &optional (octave-size 2.0) (divisions-per-octave 12)
                  ;; MDE Tue Feb  7 16:59:45 2012 -- round so we don't get tiny
                  ;; fractions of semitones due to float inaccuracies?
                  (round-to 0.0001))

## utilities/string-replace [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DESCRIPTION

     Replace specified segments of a string with a new specified string.

ARGUMENTS

     - A string that is the string segment to be replaced.
     - A string that is the string with which the specified string segment is to
       be replaced.
     - The string in which the specified segment is to be sought and replaced.

RETURN VALUE

     A string.

EXAMPLE

    (string-replace "flat" "\\flat" "bflat clarinet")

    => "b\\flat clarinet"

SYNOPSIS

    (defun string-replace (what with string)

## utilities/swap-elements [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DESCRIPTION

     Swap the order of each consecutive pair of elements in a list.

ARGUMENTS

     - A list.

RETURN VALUE

     A list.

EXAMPLE

    (swap-elements '(1 2 3 4 5 6 7 8 9 10))

    => (2 1 4 3 6 5 8 7 10 9)

    (swap-elements '(1 2 3 4 5 6 7 8 9))

    => (2 1 4 3 6 5 8 7 9)

SYNOPSIS

    (defun swap-elements (list)

## utilities/update-app-src [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DATE

     June 1st 2013

DESCRIPTION

     TEMPORARILY DISABLED DUE TO SVN SERVER ACCESS RESTRICTIONS.
     NB This function currently works in SBCL and CCL on UNIX systems only.

     For users of the slippery chicken app, this function will update the source
     code of the app to the latest in the online subversion (svn) repository.
     An internet connection is therefore necessary.

     The first time it is run it will delete the current source code and
     download all the new source code, so make sure to back up if you've
     modified the source code yourself (not recommended).  When it is run from
     then on, it will only update the source code that is out of date.

     Once the source code is updated, you'll need to restart the app or just
     Lisp for the changes to be recompiled.

     **NB** The first time you call this function, you might get a "certificate
     error".  In order to accept the certificate, start the terminal application
     and type the following:

     cd /tmp/
     svn co https://svn.ecdf.ed.ac.uk/repo/user/medward2/sc-tags/sc-latest/src

     That should give you a prompt in the terminal from which you can accept the
     certificate.  Then the next time you try it from Lisp the certificate
     should not cause a problem.

     Users without the app can always download the latest source code in a
     terminal by issuing the following command.
     svn co https://svn.ecdf.ed.ac.uk/repo/user/medward2/sc-tags/sc-latest/src

ARGUMENTS

     The full path to the slippery-chicken application, minus the last slash.
     Remember that this can't include any spaces in file/folder names

OPTIONAL ARGUMENTS

     keyword arguments:
     - :rm.  The path to the shell 'rm' command.  Default = "/bin/rm"
     - :svn.  The path to the shell 'svn' command.  Default = "/usr/bin/svn"

RETURN VALUE

     The shell return value of the call to SVN, usually 0 on success.

EXAMPLE

    Running for the first time:
    (update-app-src "/tmp/sc-app/slippery-chicken.app")
    A    /tmp/sc-app/slippery-chicken.app/Contents/Resources/sc/src/sndfile.lsp
    A    /tmp/sc-app/slippery-chicken.app/Contents/Resources/sc/src/osc.lsp
    A    /tmp/sc-app/slippery-chicken.app/Contents/Resources/sc/src/osc-sc.lsp
    [...]
    Checked out revision 3608.
    0

    or after successfully updating a previously updated version:
    ...
    At revision 3608.
    0

SYNOPSIS

    (defun update-app-src (path-to-app &key (rm "/bin/rm") (svn "/usr/bin/svn"))

## utilities/wavelab-to-audacity-marker-file [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DESCRIPTION

     Write a .txt file suitable for import to audacity with the same name and in
     the same directory as the file argument.

ARGUMENTS

     - A string that is the name of a wavelab marker file, including directory
       path and extension.

OPTIONAL ARGUMENTS

     - An integer that is the sampling rate of the sound file to which the
       wavelab marker file refers. This value will affect the times of the
       output.

RETURN VALUE

     Returns T and prints the number of markers read to the listener.

EXAMPLE

    (wavelab-to-audacity-marker-file "/path/to/24-7.mrk"  44100)

    => 51 markers read

SYNOPSIS

    (defun wavelab-to-audacity-marker-file (file &optional (sampling-rate 44100))

## utilities/wrap-list [ Functions ]

[ Top ] [ utilities ] [ Functions ]

DESCRIPTION

     Shift the elements of a list to start at a specified position and wrap to
     the beginning of the list to the list's tail.

ARGUMENTS

     - A list.
     - An integer which is the 0-based position in the original list where the
       new list is to begin.

RETURN VALUE

     A list.

EXAMPLE

    (wrap-list '(1 2 3 4 5 6 7 8 9) 4)

    => (5 6 7 8 9 1 2 3 4)

SYNOPSIS

    (defun wrap-list (list start)

## utilities/write-list-to-coll [ Functions ]

[ Top ] [ utilities ] [ Functions ]

AUTHOR

     Daniel Ross (mr.danielross[at]gmail[dot]com)

DATE

     Tue 18 Feb 2020 15:38:40 GMT

DESCRIPTION

     Turn a list of lists into a text file, formatted to be read by the MaxMSP
     [coll] object. This is a bit like gen-max-coll-file (see set-palette.lsp)
     but instead works with any data in a list.

ARGUMENTS

     - A list of lists in the form '((a b c) (d e f))

OPTIONAL ARGUMENTS

     keyword arguments
     :file - the output file. Default = "/tmp/sc-max-coll.txt"
     :base - the minimum number for coll indexing. In the resulting output file,
     each list in the list of lists will be preceeded by an (increasing) integer
     and a comma. This argument sets the base value of that integer. Default = 0.
     :capitalize - Should any outputted text be capitalized or not?
     Default = NIL.
     :if-exists - what to do if the file already exists. This argument is passed
     to with-open-file. More info here: http://clhs.lisp.se/Body/m_w_open.htm
     Default = :supercede
     :prefix - add a string prefix to the item number. Default = NIL.
     :alt-label - if you do not want the items labels to be consecutive numbers,
     then you can here either provide a list of lists or a function. If a list of
     lists, this must be the same length as the first argument. If a function, it
     must be called with the item number (which increases incrementally from
     base).

RETURN VALUE

     The output file location

EXAMPLE

    (let ((l '((hello!)(how are you?)(very well thank you.)(1 2 3 4))))
          (write-list-to-coll l :base 6))

    => "/tmp/sc-max-coll.txt"

    The resulting text file will looks like this when opened:

    6, hello!;
    7, how are you?;
    8, very well thank you.;
    9, 1 2 3 4;

    ;; DJR Tue 3 Mar 2020 13:52:34 GMT
    (let ((l '((hello!)(how are you?)(very well thank you.)(1 2 3 4))))
          (write-list-to-coll l :base 15
                              :alt-label #'(lambda (count)
                                             (let ((l '(foo bar)))
                                               (nth (mod count 2) l)))
                              :prefix "yes_"))

    => "/tmp/sc-max-coll.txt"

    The resulting text file will looks like this when opened:

    yes_bar, hello!;
    yes_foo, how are you?;
    yes_bar, very well thank you.;
    yes_foo, 1 2 3 4;

SYNOPSIS

    (defun write-list-to-coll (data-list &key (base 0)
                                           (file "/tmp/sc-max-coll.txt")
                                           (capitalize nil)
                                           (if-exists :supersede)
                                           ;; DJR Tue 3 Mar 2020 13:52:34 GMT
                                           (prefix "")
                                           alt-label)