tablekt
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## tablekt

tablekt — Provides k-rate control over table numbers.

## Description

k-rate control over table numbers.

The standard Csound opcode table when producing a k- or a-rate result, can only use an init-time variable to select the table number. tablekt accepts k-rate control as well as i-time. In all other respects they are similar to the original opcodes.

## Syntax

    ares tablekt xndx, kfn [, ixmode] [, ixoff] [, iwrap]

    kres tablekt kndx, kfn [, ixmode] [, ixoff] [, iwrap]

## Initialization

ixmode -- if 0, xndx and ixoff ranges match the length of the table. if non-zero xndx and ixoff have a 0 to 1 range. Default is 0

ixoff -- if 0, total index is controlled directly by xndx, ie. the indexing starts from the start of the table. If non-zero, start indexing from somewhere else in the table. Value must be positive and less than the table length (ixmode = 0) or less than 1 (ixmode not equal to 0). Default is 0.

iwrap -- if iwrap = 0, Limit mode: when total index is below 0, then final index is 0.Total index above table length results in a final index of the table length - high out of range total indexes stick at the upper limit of the table. If iwrap not equal to 0, Wrap mode: total index is wrapped modulo the table length so that all total indexes map into the table. For instance, in a table of length 8, xndx = 5 and ixoff = 6 gives a total index of 11, which wraps to a final index of 3. Default is 0.

## Performance

kndx -- Index into table, either a positive number range matching the table length (ixmode = 0) or a 0 to 1 range (ixmode not equal to 0).

xndx -- matching the table length (ixmode = 0) or a 0 to 1 range (ixmode not equal to 0)

kfn -- Table number. Must be >= 1. Floats are rounded down to an integer. If a table number does not point to a valid table, or the table has not yet been loaded (GEN01) then an error will result and the instrument will be de-activated.

| Caution with k-rate table numbers
At k-rate, if a table number of < 1 is given, or the table number points to a non-existent table, or to one which has a length of 0 (it is to be loaded from a file later) then an error will result and the instrument will be deactivated. kfn must be initialized at the appropriate rate using init. Attempting to load an i-rate value into kfn will result in an error.

## Examples

Here is an example of the tablekt opcode. It uses the file tablekt.csd.

Example 1076. Example of the tablekt opcode.

See the sections Real-time Audio and Command Line Flags for more information on using command line flags.

    <CsoundSynthesizer>
    <CsOptions>
    ; Select audio/midi flags here according to platform
    -odac     ;;;realtime audio out
    ;-iadc    ;;;uncomment -iadc if RT audio input is needed too
    ; For Non-realtime ouput leave only the line below:
    ; -o tablekt.wav -W ;;; for file output any platform
    </CsOptions>
    <CsInstruments>

    sr = 44100
    ksmps = 32
    nchnls = 2
    0dbfs  = 1

    seed 0

    gift1 ftgen 1, 0, 1024, 10, 1				;sine wave
    gift2 ftgen 2, 0, 1024, 10, 1, 1, 1, 1, 1, 1, 1, 1, 1	;pulse

    instr 1
    andx phasor 400 		;phasor for reading the index
    kfn init 1 			;initialize the choice of the function table
    kmetro init 1			;initialize the frequency of the metro
    knewft metro kmetro		;make a new choice for selecting the function table once a second

    if knewft == 1 then
      kfn = (kfn == 1 ? 2 : 1) 	;switch between 1 and 2
      kmetro random .5, 2 		;create new metro frequency
      printk2 kfn
    endif

    ares tablekt andx, kfn, 1
    outs ares,  ares
    endin

    </CsInstruments>
    <CsScore>
    i 1 0 10
    e
    </CsScore>
    </CsoundSynthesizer>

Its output should include lines like these:

     i1     2.00000
     i1     1.00000
     i1     2.00000
     i1     1.00000
    ....

## See also

Table Reading with Dynamic Selection

## Credits

Author: Robin Whittle
Australia
May 1997

New in version 3.47

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