The Alternative Csound Reference Manual
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# table

table -- Accesses table values by direct indexing.

## Description

Accesses table values by direct indexing.

## Syntax

ar table andx, ifn [, ixmode] [, ixoff] [, iwrap]

ir table indx, ifn [, ixmode] [, ixoff] [, iwrap]

kr table kndx, ifn [, ixmode] [, ixoff] [, iwrap]

## Initialization

ifn -- function table number.

ixmode (optional) -- index data mode. The default value is 0.

- 0 = raw index

- 1 = normalized (0 to 1)

ixoff (optional) -- amount by which index is to be offset. For a table with origin at center, use tablesize/2 (raw) or .5 (normalized). The default value is 0.

iwrap (optional) -- wraparound index flag. The default value is 0.

- 0 = nowrap (index < 0 treated as index=0; index tablesize sticks at index=size)

- 1 = wraparound.

## Performance

table invokes table lookup on behalf of init, control or audio indices. These indices can be raw entry numbers (0,l,2...size - 1) or scaled values (0 to 1-e). Indices are first modified by the offset value then checked for range before table lookup (see iwrap). If index is likely to be full scale, or if interpolation is being used, the table should have an extended guard point. table indexed by a periodic phasor ( see phasor) will simulate an oscillator.

## Examples

Here is an example of the table opcode. It uses the files table.orc and table.sco.

Example 1. Example of the table opcode.

    /* table.orc */
    ; Initialize the global variables.
    sr = 44100
    kr = 4410
    ksmps = 10
    nchnls = 1

    ; Instrument #1.
    instr 1
      ; Vary our index linearly from 0 to 1.
      kndx line 0, p3, 1

      ; Read Table #1 with our index.
      ifn = 1
      ixmode = 1
      kfreq table kndx, ifn, ixmode

      ; Generate a sine waveform, use our table values
      ; to vary its frequency.
      a1 oscil 20000, kfreq, 2
      out a1
    endin
    /* table.orc */

    /* table.sco */
    ; Table #1, a line from 200 to 2,000.
    f 1 0 1025 -7 200 1024 2000
    ; Table #2, a sine wave.
    f 2 0 16384 10 1

    ; Play Instrument #1 for 2 seconds.
    i 1 0 2
    e
    /* table.sco */

## See Also

tablei, table3, oscil1, oscil1i, osciln

## Credits

Example written by Kevin Conder.

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