The active wokspace

There is always an active Workspace. When maelzel.core is imported a new Workspace is created, which can be retrieved via getWorkspace

from maelzel.core import *
from IPython.display import display

w = getWorkspace()
w

Workspace(scorestruct=ScoreStruct(tempo=96, timesig=(3, 4)), config={}, dynamicCurve=DynamicCurve(shape=expon(0.3), mindb=-60.0, maxdb=0.0))

Alternatively the active workspace can be accessed via the active class variable, as Workspace.active

w is Workspace.active

True

The active workspace contains the working environment. The most important attributes encapsulated here are the score structure (.scorestruct) and the core configuration (.config)

Each new Workspace contains a basic ScoreStruct (4/4, quarter=60) and a copy of the root config

w.scorestruct

ScoreStruct

Meas. Index	Timesig	Tempo (quarter note)	Label	Rehearsal	Barline
0	4/4	60
...

w.config

CoreConfig: maelzel:core

Key	Value	Type	Descr
A4	442	between 10 - 10000	Freq. of the Kammerton A4. Normal values are 440, 442, 443 or 432 for old tuning, but any 'fantasy' value can be used
chordAdjustGain	True	type: bool	Adjust the gain of a chord according to the number of notes, to prevent clipping
dynamicCurveDynamics	ppp pp p mp mf f ff fff	type: str	Possible dynamic steps. A string with all dynamic steps, sorted from softest to loudest
dynamicCurveMaxdb	0	between -160 - 0	The amplitude (in dB) corresponding to the loudest dynamic
dynamicCurveMindb	-60	between -160 - 0	The amplitude (in dB) corresponding to the softest dynamic
dynamicCurveShape	expon(0.3)	type: str	The shape used to create the default dynamics curve. The most convenient shape is some variation of an exponential, given as expon(exp), where exp is the exponential used. exp < 1 will result in more resolution for soft dynamics
enharmonic.horizontalWeight	1	type: int	The weight of the horizontal dimension (note sequences) when evaluating an enharmonic variant
enharmonic.verticalWeight	0.01	type: float	The weight of the vertical dimension (chords within a voice) when evaluating an enharmonic variant
fixStringNotenames	False	type: bool	If True, pitches given as string notenames are fixed at the spelling given at creation. Otherwise pitches might be respelled to match their context for better readability. Pitches given as midi notes or frequencies are always respelled
htmlTheme	light	{dark, light}	Theme used when displaying html inside jupyter
jupyterHtmlRepr	True	type: bool	If True, output html inside jupyter as part of the _repr_html_ hook. Under certain circumstances (for example, when generating documentation from a notebook) this html might result in style conflict. Setting in False will just output plain text
lilypondpath		type: str	The path to the lilypond binary. It must be an absolute, existing path
musescorepath		type: str	The command to use when calling MuseScore. For macOS users: it must be an absolute path pointing to the actual binary inside the .app bundle
openImagesInExternalApp	False	type: bool	Force opening images with an external tool, even when inside a Jupyter notebook
play.backend	default	{alsa, auhal, default, jack, pa_cb, portaudio, pulse}	backend used for playback
play.defaultAmplitude	1.0	between 0 - 1	The amplitude of a Note/Chord when an amplitude is needed and the object has an undefined amplitude. This is only used if play.useDynamics if False
play.defaultDynamic	f	{f, ff, fff, ffff, mf, mp, p, pp, ppp, pppp}	THe dynamic of a Note/Chord when a dynamic is needed. This is only used if play.useDynamics is True. Any event with an amplitude will use that amplitude instead
play.engineName	maelzel.core	type: str	Name of the play engine used
play.fade	0.02	type: float	default fade time
play.fadeShape	cos	{cos, linear, scurve}	Curve-shape used for fading in/out
play.gain	1.0	between 0 - 1	Default gain used when playing/recording
play.generalMidiSoundfont		type: str	Path to a soundfont (sf2 file) with a general midi mapping
play.gracenoteDuration	1/14	type: (int, float, str)	Duration assigned to a gracenote for playback (in quarternotes)
play.instr	sin	type: str	Default instrument used for playback. A list of available instruments can be queried via `availableInstrs`. New instrument presets can be defined via `defPreset`
play.numChannels	2	between 1 - 128	Default number of channels (channels can be set explicitely when calling startPlayEngine
play.pitchInterpolation	linear	{cos, linear}	Curve shape for interpolating between pitches
play.schedLatency	0.05	type: float	Added latency when scheduling events to ensure time precission
play.soundfontAmpDiv	16384	type: int	A divisor used to scale the amplitude of soundfonts to a range 0-1
play.soundfontInterpolation	linear	{cubic, linear}	Interpolation used when reading sample data from a soundfont.
play.unschedFadeout	0.05	type: float	fade out when stopping a note
play.useDynamics	True	type: bool	If True, any note/chord with a set dynamic will use that to modify its playback amplitude if no explicit amplitude is set
play.verbose	False	type: bool	If True, outputs extra debugging information regarding playback
play.waitAfterStart	0.5	type: float	How much to wait for the sound engine to be operational after starting it
quant.breakSyncopationsLevel	none	{all, none, strong, weak}	Level at which to break syncopations, one of "all" (break all syncopations), "weak (break only syncopations over secondary beats)", "strong" (break syncopations at strong beats) or "none" (do not break any syncopations)
quant.complexity	high	{high, highest, low, lowest, medium}	Controls the allowed complexity in the notation. The higher the complexity, the more accurate the quantization, at the cost of a more complex notation.
quant.minBeatFractionAcrossBeats	0.5	type: float	when merging durations across beats, a merged duration cannot be smaller than this duration. This is to prevent joining durations across beats which might result in high rhythmic complexity
quant.nestedTuplets	None	{False, None, True}	Are nested tuples allowed when quantizing? Not all display backends support nested tuples (musescore, used to render musicxml has no support for nested tuples). If None, this flag is determined based on the complexity preset (quant.complexity)
quant.nestedTupletsInMusicxml	False	type: bool	If False, nested tuplets default to False when rendering to musicxml. This is because some musicxml renderers (MuseScore, for example) do not render nested tuplets properly. Nested tuplets will still be enabled if the config options "quant.nestedTuplets" is explicitely set to True.
rec.blocking	True	type: bool	Should recording be blocking or should be done async?
rec.extratime	0.0	between 0.0 - inf	Default extratime added when recording
rec.ksmps	64	{1, 16, 32, 64, 128, 256}	Samples per cycle when rendering offline (passed as ksmps to csound)
rec.numChannels	2	between 1 - 128	The default number of channels when rendering to disk
rec.path		type: str	path used to save output files when rendering offline. If not given the default can be queried via `recordPath`
rec.sr	44100	{44100, 48000, 88200, 96000, 144000, 176400, 192000, 352800, 384000}	Sample rate used when rendering offline
rec.verbose	False	type: bool	Show debug output when calling csound as a subprocess
reprShowFreq	False	type: bool	Show frequency when printing a Note in the console
semitoneDivisions	4	{1, 2, 4}	The number of divisions per semitone (2=quarter-tones, 4=eighth-tones)
show.arpeggiateChord	auto	{auto, False, True}	Arpeggiate notes of a chord when showing. In auto mode, only arpeggiate when needed
show.arpeggioDuration	0.5	type: float	Duration used for individual notes when rendering a chord as arpeggio
show.asoluteOffsetForDetachedObjects	False	type: bool	When showing an object which has a parent but is shown detached from it, shouldthe absolute offset be used?
show.autoClefChanges	True	type: bool	If True, add clef changes to a quantized part if needed. Otherwise, one clef is determined for each part and is not changed along the part.
show.backend	lilypond	{lilypond, musicxml}	method/backend used when rendering notation
show.cacheImages	True	type: bool	If True, cache rendered images. Set it to False for debugging. call `resetImageCache()` to reset manually
show.centSep	,	type: str	Separator used when displaying multiple cents deviation (in a chord)
show.centsAnnotationStyle	fontsize=6; placement=below	type: str	Style used for cents annotations. The format is a list of = pairs, separated by semicolons. Possible keys are: fontsize, box (choices: rectangle, square, circle), placement (choices: above, below), italic (flag), bold (flag). Flag keys do not need any values. Example: "fontsize=12; italic; box=rectangle"
show.centsDeviationAsTextAnnotation	True	type: bool	show cents deviation as text when rendering notation
show.clipNoteheadShape	square	{, cluster, cross, diamond, harmonic, normal, rectangle, rhombus, slash, square, triangle, xcircle}	Notehead shape to use for clips
show.fillDynamicFromAmplitude	False	type: bool	If True, when rendering notation, if an object has an amplitude and does not have an explicit dynamic, add a dynamic according to the amplitude
show.format	png	{pdf, png, repr}	Used when no explicit format is passed to .show
show.glissEndStemless	False	type: bool	When the end pitch of a gliss. is shown as gracenote, make this stemless
show.glissHideTiedNotes	True	type: bool	Hide tied notes which are part of a glissando
show.glissLineThickness	2	{1, 2, 3, 4}	Line thikness when rendering glissandi. The value is abstract and it isup to the renderer to interpret it
show.glissLineType	solid	{solid, wavy}	Default line type for glissandi
show.hideRedundantDynamics	True	type: bool	Hide redundant dynamics within a voice
show.horizontalSpacing	medium	{default, large, medium, small, xlarge}	Hint for the renderer to adjust horizontal spacing. The actual result depends on the backend and the format used.
show.jupyterMaxImageWidth	1000	type: int	A max. width in pixels for images displayed in a jupyter notebook
show.labelStyle	fontsize=9; placement=above	type: str	Text size used for labelsThe format is a list of = pairs, separated by semicolons. Possible keys are: fontsize, box (choices: rectangle, square, circle), placement (choices: above, below), italic (flag), bold (flag). Flag keys do not need any values. Example: "fontsize=12; italic; box=rectangle"
show.lilypondGlissandoMinimumLength	5	type: int	The minimum length of a glissando in points. Increase this value if glissando linesare not shown or are too short (this might be the case within the context of dottednotes or accidentals)
show.lilypondPngStaffsizeScale	1.5	type: float	A factor applied to the staffsize when rendering to png via lilypond. Useful if rendered images appear too small in a jupyter notebook
show.measureAnnotationStyle	box=rectangle; fontsize=12	type: str	Style for measure annotations. The format is a list of = pairs, separated by semicolons. Possible keys are: fontsize, box (choices: rectangle, square, circle), placement (choices: above, below), italic (flag), bold (flag). Flag keys do not need any values. Example: "fontsize=12; italic; box=rectangle"
show.pageMarginMillimeters	4	between 0 - 1000	The page margin in mm
show.pageOrientation	portrait	{landscape, portrait}	Page orientation when rendering to pdf
show.pageSize	a4	{a2, a3, a4}	The page size when rendering to pdf
show.pngResolution	200	{100, 200, 300, 600, 1200}	DPI used when rendering to png
show.referenceStaffsize	12.0	type: float	Staff size used as a reference to convert between staff size and scaling factor. This allows to use staff size as a general way to indicate the scale of a score, independent of the backend
show.rehearsalMarkStyle	box=rectangle; fontsize=13; bold	type: str	Style for rehearsal marks. The format is a list of = pairs, separated by semicolons. Possible keys are: fontsize, box (choices: rectangle, square, circle), placement (choices: above, below), italic (flag), bold (flag). Flag keys do not need any values. Example: "fontsize=12; italic; box=rectangle"
show.respellPitches	True	type: bool	If True, try to find a suitable enharmonic representation of pitches whichhave not been fixed already by the user. Otherwise the canonical form of eachpitch is used, independent of the context
show.scaleFactor	0.75	type: float	Affects the size of the generated image when using png format
show.scaleFactorMusicxml	0.8	type: float	Apply a scaling factor to images rendered via musicxml
show.staffSize	10.0	type: float	The size of a staff, in points
show.voiceMaxStaves	1	between 1 - 4	The maximum number of staves per voice when showing a Voice as notation. A voiceis a sequence of non-simultaneous events (notes, chords, etc.) but these canbe exploded over multiple staves (for example, a chord might expand across awide range and would need multiple extra lines in any clef
splitAcceptableDeviation	4	type: int	When splitting notes between staves, notes within this range of the split point will be grouped together if they all fit
.enharmonic.debug	False	type: bool	If True, print debug information while calculating automatic enharmonic spelling
.enharmonic.threeQuarterMicrotonePenalty	20	type: int	None
.quant.debug	False	type: bool	Turns on debugging for the quantization process. This will show how different divisions of the beat are being evaluated by the quantizer in terms of what is contributing more to the ranking. With this information it is possible to adjust the weights (quant.rhythmCompleityWeight, .quant.divisionErrorWeight, etc)
.quant.debugShowNumRows	50	type: int	When quantization debugging is turned on this setting limits the number of different quantization possibilities shown
.quant.divisionErrorWeight	None	type: NoneType	A weight (between 0 and 1) applied to the penalty of complex quantization of the beat. The higher this value is, the simpler the subdivision chosen. If set to None, this value is derived from the complexity preset (quant.complexity)
.quant.gridErrorExp	None	type: NoneType	An exponent applied to the grid error. The grid error is a value between 0-1 which indicates how accurate the grid representation is for a given quantization (a value of 0 indicates perfect timing). An exponent betwenn 0 < exp <= 1 will make grid errors weight more dramatically as they diverge from the most accurate solution. If None, the value is derived from the complexity setting (quant.complexity)
.quant.gridErrorWeight	None	type: NoneType	A weight (between 0 and 1) applied to the deviation of a quantization to the actual attack times and durations during quantization. The higher this value, the more accurate the quantization (possibly resulting in more complex subdivisions of the beat). If None, the value is derived from the complexity preset (quant.complexity)
.quant.rhythmComplexityWeight	None	type: NoneType	A weight (between 0 and 1) applied to the penalty calculated from the complexity of the rhythm during quantization. A higher value results in more complex rhythms being considered for quantization. If None, the value is derived from the complexity (quant.complexity)
.rec.compressionBitrate	224	type: int	default bitrate to use when encoding to ogg or mp3
.reprShowFractionsAsFloat	True	type: bool	All time offsets and durations are kept as rational numbers to avoid rounding errors. If this option is True, these fractions are printed as floats in order to make them more readable.
.show.autoClefChangesWindow	1	type: int	When adding automatic clef changes, use this window size (number of elements per evaluation)
.show.centsAnnotationPlusSign	True	type: bool	Show a plus sign for possitive cents deviations
.show.keepClefBiasFactor	2.0	type: float	The higher this value, the more priority is given to keeping the previous clef during automatic clef changes

Modifying the active Workspace vs creating a new Workspace

If you are not planning on working on multiple scores simultaneously, the most convenient way to setup your own score structure or to customize the configuration is to modify the active workspace. For example, the score structure can be set via setScoreStruct

# Reset the scorestruct to the default
setScoreStruct()

chain = Chain(r"""
    4C:0.5
    4D:2
    4E:1
""")
chain.show()
chain.rec(nchnls=1, instr='piano')

OfflineRenderer(outfile="/home/em/.local/share/maelzel/recordings/rec-2023-07-15T18:14:55.294.wav", 1 channels, 3.52 secs, 44100 Hz)

setScoreStruct(timesig=(3, 4), tempo=96)
chain.show()
chain.rec(nchnls=1, instr='piano')

OfflineRenderer(outfile="/home/em/.local/share/maelzel/recordings/rec-2023-07-15T18:12:43.483.wav", 1 channels, 2.21 secs, 44100 Hz)

Or you can create an independent Workspace with its own scorestruct:

w = Workspace(scorestruct=ScoreStruct(timesig=(5, 8), tempo=112), active=True)
chain

Chain([4C:0.5♩, 4D:2♩, 4E:1♩], dur=3.5)

Deactivating the active Workspace activates the previous workspace (there should always be an active Workspace)

w.deactivate()
chain

Chain([4C:0.5♩, 4D:2♩, 4E:1♩], dur=3.5)

As a side note, if you just want to test something under a different scorestruct, you can do use a ScoreStruct as a context manager. This clones the active Workspace with the given ScoreStruct and activates this newly created Workspace, to deactivate it when to context is exited.

with ScoreStruct(r'''
    7/16, 116
    11/16, 48
'''):
    chain.show()
    display(chain.rec(nchnls=1, instr='piano'))

OfflineRenderer(outfile="/home/em/.local/share/maelzel/recordings/rec-2023-07-15T18:14:59.880.wav", 1 channels, 3.11 secs, 44100 Hz)

The same is valid for the configuration. You can modify the active Workspace by changing its config, either via setConfig or by directly assigning to .config:

setScoreStruct()

chain = Chain(r'''
  C4+15:1
  4Eb-19:0.5
  3B+:1.5
''')
chain

Chain([4C+15:1♩, 4Eb-19:0.5♩, 3B+:1.5♩], dur=3)

config = CoreConfig()
config['show.centsDeviationAsTextAnnotation'] = False

setConfig(config)   # This is the same as calling `config.activate()`
chain

Chain([4C+15:1♩, 4Eb-19:0.5♩, 3B+:1.5♩], dur=3)

Reset the config to the root config

CoreConfig.root.activate()
chain

Chain([4C+15:1♩, 4Eb-19:0.5♩, 3B+:1.5♩], dur=3)