sc-set/tl-set [ Classes ]

[ Top ] [ sc-set ] [ Classes ]

NAME

 tl-set

 File:             tl-set.lsp

 Class Hierarchy:  named-object -> linked-named-object -> sclist -> chord ->
                   sc-set -> tl-set

 Version:          1.0.12

 Project:          slippery chicken (algorithmic composition)

 Purpose:          Implementation of the tl-set class that extends
                   set to incorporate transposition and limiting to
                   certain pitch ranges.  NB As of yet, once a set is
                   transposed or limited, it can't be retransposed from its
                   original pitches, only from the current set, i.e these
                   methods are destructive!

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

 Creation date:    13th August 2001

 $$ Last modified:  18:12:23 Fri Jan 26 2024 CET

 SVN ID: $Id$

tl-set/harp-salzedo-to-tl-set [ Functions ]

[ Top ] [ tl-set ] [ Functions ]

AUTHOR

 Ruben Philipp <me@rubenphilipp.com>

 CREATED
 2023-11-22, Essen

DESCRIPTION

 This function creates a tl-set from a list of harp pedalling indications
 (similar to those introduced by Salzedo). Thus, the resulting tl-set
 represents all producible pitches on a concert harp within a given range
 (defined by the :lowest and :highest slots). 

ARGUMENTS

 A 7-item list with the position of the pedals, where -1 indicates lowering
 the respective note a half step, 0 means no alteration, 1 means raising the
 note a half. The order of notes reflects the pedal structure of the concert
 harp (i.e. D C B E F G A). Thus, '(0 1 0 0 0 -1 0) leads to the following
 alteration: C# D E F Gb A B

OPTIONAL ARGUMENTS

 keyword-arguments:
 - :id. The id of the sc-st to be generated. 
 - :lowest. This is the lowest note to be contained in the set.
   Default = 'b0
   +slippery-chicken-standard-instrument-palette+.
 - :highest. This is the highest note to be contained in the set.
   Default = 'gs7
 - :limit-lower. A note-name symbol or a pitch object to indicate the
   lowest possible pitch in the tl-set object to be created (cf.
   make-tl-set). Default = The value of :lowest-written 'harp in
   +slippery-chicken-standard-instrument-palette+.
 - :limit-upper. A note-name symbol or a pitch object to indicate the
   highest possible pitch in the tl-set object to be created (cf.
   make-tl-set). Default = The value of :highest-written 'harp in
   +slippery-chicken-standard-instrument-palette+.
 - :subsets. Inherited from make-tl-set.
 - :related-sets. Inherited from make-tl-set.
 - :auto-sort. Inherited from make-tl-set. Default = T.

RETURN VALUE

 An tl-set generated from the given data. 

EXAMPLE

(harp-salzedo-to-tl-set '(0 0 -1 0 0 1 -1))

=>
TL-SET: transposition: 0
        limit-upper: NIL
        limit-lower: NIL
SC-SET: auto-sort: T, rm-dups: T, warn-dups: T used-notes: 
RECURSIVE-ASSOC-LIST: recurse-simple-data: T
                      num-data: 0
                      linked: NIL
                      full-ref: NIL
ASSOC-LIST: warn-not-found T
CIRCULAR-SCLIST: current 0
SCLIST: sclist-length: 0, bounds-alert: T, copy: T
LINKED-NAMED-OBJECT: previous: NIL, 
                     this: NIL, 
                     next: NIL
NAMED-OBJECT: id: USED-NOTES, tag: NIL, 
data: NIL
**************
, 

**** N.B. All pitches printed as symbols only, internally they are all 
pitch-objects.


    subsets: 
    related-sets: 
CHORD: auto-sort: T, marks: NIL, micro-tone: NIL, micro-tonality: 0.0
centroid: NIL, dissonance: NIL
SCLIST: sclist-length: 48, bounds-alert: T, copy: T
LINKED-NAMED-OBJECT: previous: NIL, 
                     this: NIL, 
                     next: NIL
NAMED-OBJECT: id: NIL, tag: NIL, 
data: (C1 D1 E1 F1 Gs1 Af1 Bf1 C2 D2 E2 F2 Gs2 Af2 Bf2 C3 D3 E3 F3 Gs3 Af3 Bf3
       C4 D4 E4 F4 Gs4 Af4 Bf4 C5 D5 E5 F5 Gs5 Af5 Bf5 C6 D6 E6 F6 Gs6 Af6 Bf6
       C7 D7 E7 F7 Gs7 Af7)
**************

SYNOPSIS

(defun harp-salzedo-to-tl-set (salzedo
                               &key
                                 id
                                 (lowest 'b0)
                                 (highest 'gs7)
                                 (limit-lower (lowest-written
                                               (get-standard-ins 'harp)))
                                 (limit-upper (highest-written
                                               (get-standard-ins 'harp)))
                                 subsets
                                 related-sets
                                 (auto-sort t))

tl-set/limit [ Methods ]

[ Top ] [ tl-set ] [ Methods ]

DESCRIPTION

 Remove pitch objects from a given tl-set whose pitch content is higher or
 lower than the pitches specified. Any pitch objects whose pitch content is
 equal to the limit pitches specified will be retained.

 NB: C0 and B10 are the highest and lowest possible pitches of the
     quarter-tone scale defined in scale.lsp (16.35 and 31608.55 Hz
     respectively).

 NB: The keyword arguments for which the lower and upper limits are to be
     specified are optional arguments, but are required in order for any
     effect to be had.

 NB: Whether a pitch is higher or lower than the specified pitches is
     determined by their frequencies. If a pitch happens to be microtonal it
     could be that the nearest pitch symbol is an approximation, i.e. not
     quite the same as the frequency, so limiting might appear to be working
     incorrectly.

ARGUMENTS

 - The tl-set object.

OPTIONAL ARGUMENTS

 keyword arguments:
 - :upper. A note-name symbol that is the upper limit for the limiting
   process.
 - :lower. A note-name symbol that is the lower limit for the limiting
   process.
 - :do-related-sets. T or NIL to indicate whether the RELATED-SETS slot of
   the given tl-set object is to be transposed as well or left unhandled. T
   = transpose. Default = NIL.

RETURN VALUE

 A tl-set object.

EXAMPLE

;;; By default the method does not transpose the pitches of the RELATED-SETS
;;; slot 
(let ((mtls (make-tl-set '(d2 f2 a2 c3 e3 g3 b3 d4 gf4 bf4 df5 f5 af5 c6)
                         :subsets '((fl (df5 f5 af5))
                                    (vla (e3 g3 b3)))
                         :related-sets '((missing (fs2 b5))))))
  (limit mtls :upper 'df5 :lower 'c3))

=> 
TL-SET: transposition: 0
        limit-upper: 
PITCH: frequency: 554.365, midi-note: 73, midi-channel: 0 
[...]
    subsets: 
FL: (DF5)
VLA: (E3 G3 B3)
    related-sets: 
MISSING: (FS2 B5)
SCLIST: sclist-length: 14, bounds-alert: T, copy: T
LINKED-NAMED-OBJECT: previous: NIL, this: NIL, next: NIL
NAMED-OBJECT: id: NIL, tag: NIL, 
data: (C3 E3 G3 B3 D4 GF4 BF4 DF5)

;; Setting the :do-related-sets argument to T results in any RELATED-SETS pitch
;; content being transposed as well
(let ((mtls (make-tl-set '(d2 f2 a2 c3 e3 g3 b3 d4 gf4 bf4 df5 f5 af5 c6)
                         :subsets '((fl (df5 f5 af5))
                                    (vla (e3 g3 b3)))
                         :related-sets '((missing (fs2 b5))))))
  (limit mtls :upper 'c6 :lower 'c3 :do-related-sets t))

=>
[...]
    subsets: 
FL: (DF5 F5 AF5)
VLA: (E3 G3 B3)
    related-sets: 
MISSING: (B5)
SCLIST: sclist-length: 14, bounds-alert: T, copy: T
LINKED-NAMED-OBJECT: previous: NIL, this: NIL, next: NIL
NAMED-OBJECT: id: NIL, tag: NIL, 
data: (C3 E3 G3 B3 D4 GF4 BF4 DF5 F5 AF5 C6)

SYNOPSIS

(defmethod limit ((tls tl-set) &key upper lower do-related-sets)

tl-set/limit-for-instrument [ Methods ]

[ Top ] [ tl-set ] [ Methods ]

DESCRIPTION

 Remove any pitch objects from the given tl-set object which are outside of
 the range of the specified instrument object. 

 The pitch objects returned after that operation can then be reduced again
 by applying further limits specified by the :upper and :lower keyword
 arguments.  

 NB: This method returns a list of pitch objects, not a tl-set object,
     though it does destructively alter the data of the given tl-set object
     accordingly. 

 NB: This method will return NIL if the pitch objects of the given tl-set
     object are microtonal while the given instrument object is set to be a
     non-microtonal instrument (see example).

 NB: Whether a pitch is higher or lower than the specified pitches is
     determined by their frequencies. If a pitch happens to be microtonal it
     could be that the nearest pitch symbol is an approximation, i.e. not
     quite the same as the frequency, so limiting might appear to be working
     incorrectly.

ARGUMENTS

 - A tl-set object.
 - An instrument object.

OPTIONAL ARGUMENTS

 keyword arguments:
 - :upper. A pitch object or note-name symbol that is the uppermost possible
   pitch (inclusive) of the pitch objects returned, as a further limitation
   after the range of the instrument object has been applied.
 - :lower. A pitch object or note-name symbol that is the lowermost possible
   pitch (inclusive) of the pitch objects returned, as a further limitation
   after the range of the instrument object has been applied.
 - :do-related-sets. T or NIL to indicate whether to apply the specified
   range restrictions to the RELATED-SETS slot of the given tl-set object as
   well. NB: These will be modified within the original tl-set object but
   not returned as part of the resulting list. T = apply to RELATED-SETS as
   well. Default = NIL.

RETURN VALUE

 A list of pitch objects.

EXAMPLE

;;; Returns a list of pitch objects, limited only by the range of the given
;;; instrument object by default
(let ((mtls (make-tl-set '(d2 f2 a2 c3 e3 g3 b3 d4 gf4 bf4 df5 f5 af5 c6)
                         :related-sets '((other-notes (b4 e5 fs5 c6)))))
      (mi (make-instrument 'flute 
                           :staff-name "Flute" :staff-short-name "Fl."
                           :lowest-written 'c4 :highest-written 'd7 
                           :starting-clef 'treble :midi-program 74 :chords nil
                           :microtones t :missing-notes '(cqs4 dqf4))))
  (limit-for-instrument mtls mi))

=>
(
PITCH: frequency: 293.665, midi-note: 62, midi-channel: 0
[...] 
data: D4
[...] 
PITCH: frequency: 369.994, midi-note: 66, midi-channel: 0 
[...] 
data: GF4
[...] 
PITCH: frequency: 466.164, midi-note: 70, midi-channel: 0 
[...] 
data: BF4
[...] 
PITCH: frequency: 554.365, midi-note: 73, midi-channel: 0 
[...] 
data: DF5
[...] 
PITCH: frequency: 698.456, midi-note: 77, midi-channel: 0 
[...] 
data: F5
[...] 
PITCH: frequency: 830.609, midi-note: 80, midi-channel: 0 
[...] 
data: AF5
[...] 
PITCH: frequency: 1046.502, midi-note: 84, midi-channel: 0 
[...] 
data: C6
)

;;; Further restrict the pitches returned by setting values for the :upper and
;;; :lower keyword arguments and print the new pitch content of the given
;;; tl-set object to see the destructive modification
(let ((mtls (make-tl-set '(d2 f2 a2 c3 e3 g3 b3 d4 gf4 bf4 df5 f5 af5 c6)
                         :related-sets '((other-notes (b4 e5 fs5 c6)))))
      (mi (make-instrument 'flute 
                           :staff-name "Flute" :staff-short-name "Fl."
                           :lowest-written 'c4 :highest-written 'd7 
                           :starting-clef 'treble :midi-program 74 :chords nil
                           :microtones t :missing-notes '(cqs4 dqf4))))
  (limit-for-instrument mtls mi :upper 'b5 :lower 'c5)
  (pitch-symbols mtls))

=> (DF5 F5 AF5)

;;; By default the RELATED-SETS slot of the given tl-set object is not affected 
(let ((mtls (make-tl-set '(d2 f2 a2 c3 e3 g3 b3 d4 gf4 bf4 df5 f5 af5 c6)
                         :related-sets '((other-notes (b4 e5 fs5 c6)))))
      (mi (make-instrument 'flute 
                           :staff-name "Flute" :staff-short-name "Fl."
                           :lowest-written 'c4 :highest-written 'd7 
                           :starting-clef 'treble :midi-program 74 :chords nil
                           :microtones t :missing-notes '(cqs4 dqf4))))
  (limit-for-instrument mtls mi :upper 'b5 :lower 'c5)
  (loop for nobj in (data (related-sets mtls)) 
     collect (loop for p in (data nobj) 
                collect (data p))))

=> ((B4 E5 FS5 C6))


;;; Setting the :do-related-sets argument to T will cause the method to be
;;; applied to the RELATED-SETS slot as well.
(let ((mtls (make-tl-set '(d2 f2 a2 c3 e3 g3 b3 d4 gf4 bf4 df5 f5 af5 c6)
                         :related-sets '((other-notes (b4 e5 fs5 c6)))))
      (mi (make-instrument 'flute 
                           :staff-name "Flute" :staff-short-name "Fl."
                           :lowest-written 'c4 :highest-written 'd7 
                           :starting-clef 'treble :midi-program 74 :chords nil
                           :microtones t :missing-notes '(cqs4 dqf4))))
  (limit-for-instrument mtls mi :upper 'b5 :lower 'c5 :do-related-sets t)
  (print (pitch-symbols mtls))
  (print (loop for nobj in (data (related-sets mtls)) 
            collect (loop for p in (data nobj) 
                       collect (data p)))))

=>
(DF5 F5 AF5) 
((E5 FS5))

;;; The method will return NIL if a set of only microtonal pitches (which
;;; e.g. ring-mod might return) is given in combination with an instrument
;;; object which is not microtone-capable (such as the 'piano object of the
;;; +slippery-chicken-standard-instrument-palette+ 
(let ((mtls (make-tl-set '(dqs2 fqs2 aqf2 gqs3 bqf3 gqf4 bqf4 dqf5 fqs5)))
      (pno (get-data 'piano 
                     +slippery-chicken-standard-instrument-palette+)))
  (limit-for-instrument mtls pno :lower 'e5 :upper 'd6))

=> NIL

SYNOPSIS

(defmethod limit-for-instrument ((tls tl-set) (ins instrument)
                                 &key upper lower do-related-sets)

tl-set/limit-shift-octave [ Methods ]

[ Top ] [ tl-set ] [ Methods ]

DATE

 August 18th 2015, Edinburgh

DESCRIPTION

 Like the limit method, we restrict pitches in the set to be within
 specified limits, but instead of removing pitches we shift them to octaves
 within the limits. Rather than just putting the outlying pitches up or down
 and octave or two, we put them into the least-used octave of the set so as
 to balance pitch spread.

ARGUMENTS

 - the tl-set object

OPTIONAL ARGUMENTS

 keyword arguments:
 - :upper. A note-name symbol that is the upper limit for the limiting
   process.
 - :lower. A note-name symbol that is the lower limit for the limiting
   process.
 - :do-related-sets. T or NIL to indicate whether the RELATED-SETS slot of
   the given tl-set object is to be transposed as well or left unhandled. T
   = transpose. Default = NIL.
 - :highest-wins. T or NIL to indicate whether in the case of a tie when
   searching for the least used octave in a set, the highest octave will be
   used to move notes into. Default = T.

RETURN VALUE

 The tl-set object.

EXAMPLE

;;; the C2 will be shifted to C5 as the 5th octave is the least used in the
;;; original set. The DS5 will be shifted down to DS2 as once we've shifted the
;;; C2, the second octave is now the least used, plus it's within range.
(get-pitch-symbols
 (limit-shift-octave (make-tl-set '(c2 e2 cs3 f3 g3 d4 a4 ds5))
                     :upper 'c5 :lower 'd2))
--> (DS2 E2 CS3 F3 G3 D4 A4 C5)

SYNOPSIS

(defmethod limit-shift-octave ((tls tl-set)
                               &key upper lower (highest-wins t)
                                 do-related-sets)

tl-set/make-tl-set [ Functions ]

[ Top ] [ tl-set ] [ Functions ]

DESCRIPTION

 Create a tl-set object, which extends the sc-set class by incorporating
 transposition and limiting to certain pitch ranges. 
 
 NB: As of yet, once a set is transposed or limited, it can't be
     re-transposed from its original pitches, only from the current set; i.e
     these methods are destructive!

ARGUMENTS

 - A list of note-name symbols that is to be the set (pitch-set) for the
   given tl-set object.

OPTIONAL ARGUMENTS

 keyword arguments:
 - :id. A symbol that is to be the ID of the given tl-set object.
 - :subsets. An assoc-list of key/data pairs, in which the data is a list of
   note-name symbols that are a subset of the main set. One use for this
   keyword argument might be to create subsets that particular instruments
   can play; these would then be selected in the chord-function passed to
   the instrument object.
 - :related-sets. An assoc-list of key/data pairs, similar to :subsets, only
   that the pitches given here do not have to be part of the main set. This
   can be used, for example, for pitches missing from the main set.
 - :limit-upper. A note-name symbol or a pitch object to indicate the
   highest possible pitch in the tl-set object to be created.
 - :limit-lower.  A note-name symbol or a pitch object to indicate the
   lowest possible pitch in the tl-set object to be created.
 - :transposition. A number that is the number of semitones by which the
   pitches of the new tl-set are to be transposed when the object is
   created. Default = 0.
 - :auto-sort. T or NIL to indicate whether the specified pitches (note-name
   symbols) are to be automatically sorted from lowest to highest. T =
   sort. Default = T.
 - :tag. The tag (symbol, string) to be attached to the object; from the
   named-object base class. Default = NIL.
 - :warn-dups. To or NIL to indicate whether a warning should be issued if
   duplicate pitches are found. Default = T.

RETURN VALUE

 A tl-set object.

EXAMPLE

;; Simple usage with default values for keyword arguments
(make-tl-set '(d2 f2 a2 c3 e3 g3 b3 d4 gf4 bf4 df5 f5 af5 c6))

=> 
TL-SET: transposition: 0
        limit-upper: NIL
        limit-lower: NIL
SC-SET: auto-sort: T, used-notes: 
RECURSIVE-ASSOC-LIST: recurse-simple-data: T
                      num-data: 0
                      linked: NIL
                      full-ref: NIL
ASSOC-LIST: warn-not-found T
CIRCULAR-SCLIST: current 0
SCLIST: sclist-length: 0, bounds-alert: T, copy: T
LINKED-NAMED-OBJECT: previous: NIL, this: NIL, next: NIL
NAMED-OBJECT: id: USED-NOTES, tag: NIL, 
data: NIL

N.B. All pitches printed as symbols only, internally they are all 
pitch-objects.

    subsets: 
    related-sets: 
SCLIST: sclist-length: 14, bounds-alert: T, copy: T
LINKED-NAMED-OBJECT: previous: NIL, this: NIL, next: NIL
NAMED-OBJECT: id: NIL, tag: NIL, 
data: (D2 F2 A2 C3 E3 G3 B3 D4 GF4 BF4 DF5 F5 AF5 C6)

;; Adding subsets and related-sets
(make-tl-set '(d2 f2 a2 c3 e3 g3 b3 d4 gf4 bf4 df5 f5 af5 c6)
             :subsets '((fl (df5 f5 af5))
                        (vla (e3 g3 b3)))
             :related-sets '((missing (fs2 b5))))
=> 
TL-SET: transposition: 0
[...]
    subsets: 
FL: (DF5 F5 AF5)
VLA: (E3 G3 B3)
    related-sets: 
MISSING: (FS2 B5)
SCLIST: sclist-length: 14, bounds-alert: T, copy: T
LINKED-NAMED-OBJECT: previous: NIL, this: NIL, next: NIL
NAMED-OBJECT: id: NIL, tag: NIL, 
data: (D2 F2 A2 C3 E3 G3 B3 D4 GF4 BF4 DF5 F5 AF5 C6)

;; Limiting the pitch range of the tl-set object, once using a note-name
;; symbol and once using a pitch object
(make-tl-set '(d2 f2 a2 c3 e3 g3 b3 d4 gf4 bf4 df5 f5 af5 c6)
             :limit-upper 'g5
             :limit-lower (make-pitch 'd3))

=> 
TL-SET: transposition: 0
        limit-upper: 
PITCH: frequency: 783.991, midi-note: 79, midi-channel: 0 
[...]
        limit-lower: 
PITCH: frequency: 146.832, midi-note: 50, midi-channel: 0 
[...]
data: (E3 G3 B3 D4 GF4 BF4 DF5 F5)

;; Applying a transposition by semitones
(make-tl-set '(d2 f2 a2 c3 e3 g3 b3 d4 gf4 bf4 df5 f5 af5 c6)
             :transposition 3)

=>
TL-SET: transposition: 3
[...]
data: (F2 AF2 C3 EF3 G3 BF3 D4 F4 A4 CS5 E5 AF5 B5 EF6)

SYNOPSIS

(defun make-tl-set (set &key id tag subsets related-sets
                          limit-upper limit-lower
                          (rm-dups t) (warn-dups t)
                          (transposition 0)
                          (auto-sort t))

tl-set/stack [ Methods ]

[ Top ] [ tl-set ] [ Methods ]

DESCRIPTION

 Extend the pitch content of a given sc-set object by adding new pitch
 objects which have the same interval structure as the original set. 

 NB: See documentation for the stack method in the sc-set class for usage. 

SYNOPSIS

(defmethod stack ((tls tl-set) num-stacks &key id by-freq)

tl-set/transpose [ Methods ]

[ Top ] [ tl-set ] [ Methods ]

DESCRIPTION

 Transpose the pitches of a given tl-set by a specified number of
 semitones. 

 The contents of the SUBSETS slot are automatically transposed as well, but
 the RELATED-SETS slot is left untransposed by default. An optional argument
 allows for RELATED-SETS slot to be transposed as well.

ARGUMENTS

 - A tl-set object.
 - A positive or negative integer that is the number of semitones by which
   the pitch content of the given tl-set object is to be transposed.

OPTIONAL ARGUMENTS

 keyword arguments:
 - :do-related-sets. T or NIL to indicate whether to transpose any contents
   of the RELATED-SETS slot as well. T = transpose.  Default = NIL.
 (- additional <ignore> arguments are for internal use only)

RETURN VALUE

 The tl-set object.

EXAMPLE

;; By default the RELATED-SETS are left untransposed
(let ((mtls (make-tl-set '(d2 f2 a2 c3 e3 g3 b3 d4 gf4 bf4 df5 f5 af5 c6)
                         :subsets '((fl (df5 f5 af5))
                                    (vla (e3 g3 b3)))
                         :related-sets '((missing (fs2 b5))))))
  (transpose mtls 3))

=> 
TL-SET: transposition: 3
        limit-upper: NIL
        limit-lower: NIL
SC-SET: auto-sort: T, used-notes: 
[...]
    subsets: 
FL: (E5 AF5 B5)
VLA: (G3 BF3 D4)
    related-sets: 
MISSING: (FS2 B5)
SCLIST: sclist-length: 14, bounds-alert: T, copy: T
LINKED-NAMED-OBJECT: previous: NIL, this: NIL, next: NIL
pNAMED-OBJECT: id: NIL, tag: NIL, 
data: (F2 AF2 C3 EF3 G3 BF3 D4 F4 A4 CS5 E5 AF5 B5 EF6)

;; Set the <do-related-sets> argument to T for the RELATED-SETS contents to be
;; transposed as well
(let ((mtls (make-tl-set '(d2 f2 a2 c3 e3 g3 b3 d4 gf4 bf4 df5 f5 af5 c6)
                         :subsets '((fl (df5 f5 af5))
                                    (vla (e3 g3 b3)))
                         :related-sets '((missing (fs2 b5))))))
  (transpose mtls 3 :do-related-sets t))

=> 
TL-SET: transposition: 3
        limit-upper: NIL
        limit-lower: NIL
SC-SET: auto-sort: T, used-notes: 
[...]
    subsets: 
FL: (E5 AF5 B5)
VLA: (G3 BF3 D4)
    related-sets: 
MISSING: (A2 D6)
SCLIST: sclist-length: 14, bounds-alert: T, copy: T
LINKED-NAMED-OBJECT: previous: NIL, this: NIL, next: NIL
NAMED-OBJECT: id: NIL, tag: NIL, 
data: (F2 AF2 C3 EF3 G3 BF3 D4 F4 A4 CS5 E5 AF5 B5 EF6)

SYNOPSIS

(defmethod transpose :before ((tls tl-set) semitones 
                              &key destructively do-related-sets
                                ;; MDE Wed Aug 22 09:43:29 2018
                                lowest highest)