NEWS.md

In musicMCT: Analyze the Structure of Musical Scales

musicMCT 0.5.0

• New vignette (mct_symmetries.Rmd) explains the use of ineqsym() and related functions.
• ineqsym() now returns the correct permutation matrix when involution=TRUE. Previously, the involution parameter affected returned sets but not returned permutation matrices.
• make_infrared_ineqmat() now defaults to TRUE rather than FALSE for its include_wraparound argument.
• New monochrome_vl() detects instances where the voice leading between two modes of a scale cannot be decomposed by passing through some mode of a given contrasting scale.
• New vl_signvector() is a wrapper for signvector() that interprets inputs as voice leadings rather than scales.

musicMCT 0.4.0

New functions

• New move_to_hyperplane() finds the point where a chosen line and hyperplane intersect.
• New point_on_flat() generates a concrete point on any given flat of a hyperplane arrangement.

Updates to function ineqsym()

• The function can now return a permutation matrix rather than a scale, which it does if set is NULL. New parameter card goes along with this change: it is necessary to specify the size of the permutation matrix if set is NULL.
• Default value of parameter set is now NULL.
• Change to the way the parameter a is interpreted. Essentially it is now the inverse (mod card) of the previous implementation of a. The new method enhances consistency with other standards and with the permutation-matrix view of the function.
• Changes to the internal logic of the function, emphasizing the role of permutation matrices in implementing the symmetries of the space.

Bug fixes and minor functionality updates

• Fixes for clampitt_q(), so that it gives correct results when set includes transpositionally symmetrical subsets or doubled notes.
• ianring() gains is_interactive parameter which allows explicit control over whether the function opens a browser window (mainly to disable the browser during tests).
• project_onto() now works for hyperplane arrangements that are not central, such as those from make_roth_ineqmat() and make_rosy_ineqmat().
• scale_palette() gains an ineqmat parameter, which improves completeness of results for arrangements other than the modal color theory arrangement.

musicMCT 0.3.0

• brightness_comparisons() and brightnessgraph() gain a goal parameter that allows voice-leading brightness relationships between different sets to be studied.
• New clampitt_q() finds the sets that are "Q-related" to an input (Clampitt 1997, 2007).
• colornum() now tries to automatically match a signvector list to the specified ineqmat when the parameter signvector_list is NULL. (For instance, colornum(set, ineqmat="pastel") searches the global environment for pastel_signvectors.)
• New fpmod() allows for safer modulo division in contexts with octave equivalence.
• New inter_vlsig() finds elementary voice leadings between sets of different Tn-types.
• New make_infrared_ineqmat() adds a new family of hyperplane arrangements for studying voice leading.
• minimize_vl() now returns better results when method="hamming" by allowing for voice crossings (#4).
• primary_colornum() gains a signvector_list parameter to pass to colornum(), allowing it to work properly for hyperplane arrangements other than the "modal color theory" arrangement.
• Parameter n for tni() gains a default value of NULL, in which case the index n is chosen to create the contextual inversion which keeps the first and last entries of set fixed.
• vl_generators() now gives correct results for sets which fail optc_test().
• vlsig() parameter index now defaults to NULL, returning a matrix of all elementary voice-leadings.

More flexible handling of OPTIC symmetries

• New normal_form() calculates the normal form of a set under any combination of OPTIC symmetries, following the algorithm described by Hook (2023, 416-8).
• Set theory functions including tn(), tni(), startzero(), and so on gain an optic parameter, which allows the user to specify the OPTIC symmetries to consider.

Anaglyph Arrangements

• New make_anaglyph_ineqmat() allows construction of a new family of hyperplane arrangements (anaglyph arrangements) which study voice leadings between sets of different set classes.
• New anazero_fingerprint() provides granular information about the types of hyperplanes that a pair of sets lie on in the anaglyph arrangement.
• New behavior for howfree() and colornum() because anaglyph arrangements require special handling.

musicMCT 0.2.0

New ineqmat features

• New make_black_ineqmat() and make_gray_ineqmat() allow new transposition-sensitive hyperplane arrangements to be studied; ineqmat parameter for other functions (e.g. signvector() now accepts "black" and "gray" as options.
• New make_offset_ineqmat() creates version of standard ineqmats (MCT, white, black, etc.) which have been translated to be centered on an arbitrary set.
• Creation functions for ineqmats (makeineqmat(), make_black_ineqmat(), make_white_ineqmat(), make_roth_ineqmat()) now return a consistent value (integer(0)) rather than various errors when card is small.
• New data set roth_ineqmats.rda with precomputed results from make_roth_ineqmat(); accessed with new get_roth_ineqmat().
• New data sets for pastel and white arrangements (for cardinalities <= 6) uploaded to modalcolortheory repository and linked in the documentation for make_white_ineqmat().

New behaviors for quantization functions

• Affected functions are quantize_color(), quantize_hue(), and set_from_signvector().
• Upon failure, quantization functions now return a result whose format matches expected success format depending on value of reconvert parameter. That is, if reconvert=TRUE, failure to quantize results in a NA vector (as before), but if reconvert=FALSE, failure to quantize results in a list with entries set and edo, both of which are NA.
• Quantization functions gain a target_edo parameter, which allows user to search for desired scales in a specific edo rather than all possible edos.

New Functions

• New clockface() offers a simple plotting mechanism to visualize sets on a pitch-class clockface (with numbers corresponding to any equal temperament).
• New ianring() creates a convenient way to open a browser window to information about the input set on Ian Ring's website The Exciting Universe of Music Theory.
• New functions for basic applications of the DFT to set theory are added. These include set_to_distribution(), distribution_to_set(), and dft().

Updates to Existing Functions

• brightnessgraph() now returns an invisible copy of the igraph graph object underlying the plotted brightness graph, instead of an invisible NULL.
• sim() gains a goal parameter, which allows it to calculate the interscalar interval matrix for two sets.
• vl_generators() now throws a warning instead of an error when set is perfectly even, returning a 2-by-0 matrix.

musicMCT 0.1.2

• Updated writeSCL() to require user to enter a path.
• Updated vignette "Visualizing Higher Dimensions" to reset par() changes.

musicMCT 0.1.1

• Removed extraneous license file.

musicMCT 0.1.0

• Initial CRAN submission.

musicMCT documentation built on June 21, 2026, 9:06 a.m.