Csound.Tab

Creating Function Tables (Buffers)

Documentation

If you are not familliar with Csound's conventions you are pobably not aware of the fact that for efficiency reasons Csound requires that table size is equal to power of 2 or power of two plus one which stands for guard point (you do need guard point if your intention is to read the table once but you don't need the guard point if you read the table in many cycles, then the guard point is the the first point of your table).

data Tab :: *

Tables (or arrays)

Instances

IfB Tab

Tuple Tab

Arg Tab

Val Tab

Default Tab

type BooleanOf Tab = BoolD

type Snap Tab = Tab

noTab :: Tab

The default table. It's rendered to (-1) in the Csound.

Table querries

nsamp :: Tab -> D

nsamp — Returns the number of samples loaded into a stored function table number.

nsamp(x) (init-rate args only)

csound doc: http://www.csounds.com/manual/html/nsamp.html

ftlen :: Tab -> D

Returns a length of the table.

ftsr :: Tab -> D

Returns the sample rate for a table that stores wav files

ftchnls :: Tab -> D

Returns the number of channels for a table that stores wav files

ftcps :: Tab -> D

Returns the base frequency for a table that stores wav files

Table granularity

data TabFi :: *

Table size fidelity (how many points in the table by default).

Instances

Default TabFi

fineFi :: Int -> [(Int, Int)] -> TabFi

Sets different table size for different GEN-routines.

fineFi n ps 

where

• n is the default value for table size (size is a n power of 2) for all gen routines that are not listed in the next argument ps.
• ps is a list of pairs (genRoutineId, tableSizeDegreeOf2) that sets the given table size for a given GEN-routine.

with this function we can set lower table sizes for tables that are usually used in the envelopes.

coarseFi :: Int -> TabFi

Sets the same table size for all tables.

coarseFi n

where n is a degree of 2. For example, n = 10 sets size to 1024 points for all tables by default.

Fill table with numbers

doubles :: [Double] -> Tab

Table contains all provided values (table is extended to contain all values and to be of the power of 2 or the power of two plus one). (by default it skips normalization).

Create new tables to write/update data

newTab :: D -> SE Tab

Creates a new table. The Tab could be used while the instrument is playing. When the instrument is retriggered the new tab is allocated.

newTab size

newGlobalTab :: D -> SE Tab

Creates a new global table. It's generated only once. It's persisted between instrument calls.

newGlobalTab identifier size

tabSizeSeconds :: D -> D

Calculates the number of samples needed to store the given amount of seconds. It multiplies the value by the current sample rate.

tabSizePower2 :: D -> D

Calculates the closest power of two value for a given size.

tabSizeSecondsPower2 :: D -> D

Calculates the closest power of two value in samples for a given size in seconds.

Read from files

data WavChn

Constructors

WavLeft

WavRight

WavAll

Instances

Eq WavChn

Show WavChn

Default WavChn

data Mp3Chn

Constructors

Mp3Mono

Mp3Stereo

Mp3Left

Mp3Right

Mp3All

Instances

Eq Mp3Chn

Show Mp3Chn

Default Mp3Chn

wavs :: String -> Double -> WavChn -> Tab

Loads wav or aiff file to table

wavs fileName skipTime channel

skipTime specifies from what second it should read the file.

with channel argument we can read left, right or both channels.

mp3s :: String -> Double -> Mp3Chn -> Tab

Loads mp3 file to table:

mp3s fileName skipTime format

skipTime specifies from what second it should read the file.

format is: 1 - for mono files, 2 - for stereo files, 3 - for left channel of stereo file, 4 for right channel of stereo file

(In)Harmonic series

type PartialStrength = Double

type PartialNumber = Double

type PartialPhase = Double

type PartialDC = Double

sines :: [PartialStrength] -> Tab

Series of harmonic partials:

sine = sines [1]

saw = sines $ fmap (1 / ) [1 .. 10]

square = sines $ fmap (1 / ) [1, 3 .. 11]

triangle = sines $ zipWith (\a b -> a / (b ** 2)) (cycle [1, -1]) [1, 3 .. 11]

sines3 :: [(PartialNumber, PartialStrength, PartialPhase)] -> Tab

Specifies series of possibly inharmonic partials.

sines2 :: [(PartialNumber, PartialStrength)] -> Tab

Just like sines3 but phases are set to zero.

sines1 :: [PartialNumber] -> Tab

Just like sines2 but partial strength is set to one.

sines4 :: [(PartialNumber, PartialStrength, PartialPhase, PartialDC)] -> Tab

Specifies series of possibly inharmonic partials with direct current.

buzzes :: Double -> [Double] -> Tab

Generates values similar to the opcode buzz.

buzzes numberOfHarmonics [lowestHarmonic, coefficientOfAttenuation]

With buzzes n [l, r] you get n harmonics from l that are attenuated by the factor of r on each step.

Special cases

sine :: Tab

Table for pure sine wave.

cosine :: Tab

Table for pure cosine wave.

sigmoid :: Tab

Table for sigmoid wave.

Interpolants

All funtions have the same shape of arguments:

fun [a, n1, b, n2, c, ...]

where

• a, b, c .. - are ordinate values
• n1, n2 .. - are lengths of the segments relative to the total number of the points in the table

Csounders, Heads up! all segment lengths are relative to the total sum of the segments. You don't need to make the sum equal to the number of points in the table. Segment's lengths will be resized automatically. For example if we want to define a curve that rises to 1 over 25% of the table and then falls down to zero we can define it like this:

lins [0, 0.25, 1, 0.75, 0] 

or

lins [0, 25, 1, 75, 0]

or

lins [0, 1, 1, 3, 0]

all these expressions are equivalent.

consts :: [Double] -> Tab

Constant segments (sample and hold).

consts [a, n1, b, n2, c, ...]

where

• a, b, c .. - are ordinate values
• n1, n2, ... are lengths of the segments relative to the total number of the points in the table

lins :: [Double] -> Tab

Segments of straight lines.

lins [a, n1, b, n2, c, ...]

where

• a, b, c .. - are ordinate values
• n1, n2, ... are lengths of the segments relative to the total number of the points in the table

cubes :: [Double] -> Tab

Segments of cubic polynomials.

cubes [a, n1, b, n2, c, ...]

where

• a, b, c .. - are ordinate values
• n1, n2, ... are lengths of the segments relative to the total number of the points in the table

exps :: [Double] -> Tab

Segments of the exponential curves.

exps [a, n1, b, n2, c, ...]

where

• a, b, c, ... are ordinate values
• n1, n2, ... are lengths of the segments relative to the total number of the points in the table

splines :: [Double] -> Tab

Cubic spline curve.

splines [a, n1, b, n2, c, ...]

where

• a, b, c .. - are ordinate values
• n1, n2, ... are lengths of the segments relative to the total number of the points in the table

startEnds :: [Double] -> Tab

Creates a table from a starting value to an ending value.

startEnds [val1, dur1, type1, val2, dur2, type2, val3, ... typeX, valN]

• val1, val2 ... -- end points of the segments
• dur1, dur2 ... -- durations of the segments
• type1, type2 ... -- if 0, a straight line is produced. If non-zero, then it creates the following curve, for dur steps:

beg + (end - beg) * (1 - exp( i*type)) / (1 - exp(type * dur))

• beg, end - end points of the segment
• dur - duration of the segment

Equally spaced interpolants

econsts :: [Double] -> Tab

Equally spaced constant segments.

econsts [a, b, c, ...] 

is the same as

consts [a, 1, b, 1, c, ...]

elins :: [Double] -> Tab

Equally spaced segments of straight lines.

elins [a, b, c, ...] 

is the same as

lins [a, 1, b, 1, c, ...]

ecubes :: [Double] -> Tab

Equally spaced segments of cubic polynomials.

ecubes [a, b, c, ...] 

is the same as

cubes [a, 1, b, 1, c, ...]

eexps :: [Double] -> Tab

Equally spaced segments of exponential curves.

eexps [a, b, c, ...] 

is the same as

exps [a, 1, b, 1, c, ...]

esplines :: [Double] -> Tab

Equally spaced spline curve.

esplines [a, b, c, ...] 

is the same as

splines [a, 1, b, 1, c, ...]

estartEnds :: [Double] -> Tab

Equally spaced interpolation for the function startEnds

estartEnds [val1, type1, val2, typ2, ...]

is the same as

estartEnds [val1, 1, type1, val2, 1, type2, ...]

Polynomials

polys :: Double -> Double -> [Double] -> Tab

Polynomials.

polys xl xr [c0, c1, c2, ..]

where

• xl, xr - left and right values of the interval over wich polynomial is defined
• [c0, c1, c2, ...] -- coefficients of the polynomial

c0 + c1 * x + c2 * x * x + ...

chebs1 :: Double -> Double -> [Double] -> Tab

Chebyshev polynomials of the first kind.

polys xl xr [h0, h1, h2, ..]

where

• xl, xr - left and right values of the interval over wich polynomial is defined
• [h0, h1, h2, ...] -- relative strength of the partials

chebs2 :: Double -> Double -> [Double] -> Tab

Chebyshev polynomials of the second kind.

polys xl xr [h0, h1, h2, ..]

where

• xl, xr - left and right values of the interval over wich polynomial is defined
• [h0, h1, h2, ...] -- relative strength of the partials

bessels :: Double -> Tab

Modified Bessel function of the second kind, order 0 (for amplitude modulated FM).

bessels xint

the function is defined within the interval [0, xint].

Windows

winHamming :: [Double] -> Tab

winHanning :: [Double] -> Tab

winBartlett :: [Double] -> Tab

winBlackman :: [Double] -> Tab

winHarris :: [Double] -> Tab

winGaussian :: [Double] -> Tab

winKaiser :: [Double] -> Tab

winRectangle :: [Double] -> Tab

winSync :: [Double] -> Tab

Low level Csound definition.

gen :: Int -> [Double] -> Tab

Creates a table of doubles (It's f-table in Csound). Arguments are:

• identificator of the GEN routine
• GEN routine arguments

All tables are created at 0 and memory is never released.

Modify tables

skipNorm :: Tab -> Tab

Skips normalization (sets table size to negative value)

forceNorm :: Tab -> Tab

Force normalization (sets table size to positive value). Might be useful to restore normalization for table doubles.

setSize :: Int -> Tab -> Tab

Sets an absolute size value. As you can do it in the Csound files.

setDegree :: Int -> Tab -> Tab

Sets the relative size value. You can set the base value in the options (see tabResolution at CsdOptions, with tabResolution you can easily change table sizes for all your tables). Here zero means the base value. 1 is the base value multiplied by 2, 2 is the base value multiplied by 4 and so on. Negative values mean division by the specified degree.

guardPoint :: Tab -> Tab

Adds guard point to the table size (details of the interpolation schemes: you do need guard point if your intention is to read the table once but you don't need the guard point if you read table in many cycles, the guard point is the the first point of your table).

gp :: Tab -> Tab

Shortcut for guardPoint.

Handy shortcuts

handy shortcuts for the function setDegree.

lllofi :: Tab -> Tab

Sets degrees from -3 to 3.

llofi :: Tab -> Tab

Sets degrees from -3 to 3.

lofi :: Tab -> Tab

Sets degrees from -3 to 3.

midfi :: Tab -> Tab

Sets degrees from -3 to 3.

hifi :: Tab -> Tab

Sets degrees from -3 to 3.

hhifi :: Tab -> Tab

Sets degrees from -3 to 3.

hhhifi :: Tab -> Tab

Sets degrees from -3 to 3.

Identifiers for GEN-routines

Low level Csound integer identifiers for tables. These names can be used in the function fineFi

idWavs :: Int

idMp3s :: Int

idDoubles :: Int

idSines :: Int

idSines3 :: Int

idSines2 :: Int

idPartials :: Int

idSines4 :: Int

idBuzzes :: Int

idConsts :: Int

idLins :: Int

idCubes :: Int

idExps :: Int

idSplines :: Int

idStartEnds :: Int

idPolys :: Int

idChebs1 :: Int

idChebs2 :: Int

idBessels :: Int

idWins :: Int

Tabular opcodes

tablewa :: Tab -> Sig -> Sig -> SE Sig

Writes tables in sequential locations.

This opcode writes to a table in sequential locations to and from an a-rate variable. Some thought is required before using it. It has at least two major, and quite different, applications which are discussed below.

kstart tablewa kfn, asig, koff

csound docs: http://www.csounds.com/manual/html/tablewa.html

sec2rel :: Tab -> Sig -> Sig

Transforms phasor that is defined in seconds to relative phasor that ranges in 0 to 1.