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ptableiw

Writes a value to a function table at initialization.

This opcode is deprecated. Use the i-rate form of tablew in new code. The old name remains available for compatibility.

Syntax

ptableiw(isig, indx, ifn [, ixmode] [, ixoff] [, iwgmode])

ptableiw isig, indx, ifn [, ixmode] [, ixoff] [, iwgmode]

Initialization

isig is the value to write. indx selects a location in the existing function table ifn. All arguments are i-rate. The opcode writes once when initialization reaches the call and has no output.

ixmode defaults to 0 for indices in table sample units. A nonzero value uses normalized indices, where 1 corresponds to the table length.

ixoff adds an offset to indx in the same units. It defaults to 0.

iwgmode defaults to 0. Mode 0 limits the index to the first or last sample. Mode 1 wraps the index within the table. Mode 2 rounds and wraps the index, and also updates the guard point when writing sample 0.

The table may have any length. These arguments use the same implementation as i-rate tablew.

Replacement

Change the name and keep all arguments at i-rate to preserve initialization timing.

// Old name
ptableiw(0.5, 3, ifn)
// Supported name
tablew(0.5, 3, ifn)

This differs from ptablew, which writes during performance even when its value and index are constants. When replacing a performance-rate ptablew call, use k-rate or a-rate value and index arguments with tablew.

Examples

The example writes to two tables using the old and supported names, then reads both during initialization. Both values print as 10.

Replace an initialization-time table write
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<CsoundSynthesizer>
<CsOptions>
-n -d
</CsOptions>
<CsInstruments>
sr = 48000
ksmps = 32
nchnls = 1
0dbfs = 1

instr 1
  ptableiw(10, 0, 1)
  tablew(10, 0, 2)
  iOld = table(0, 1)
  iNew = table(0, 2)
  prints "Old name = %.0f, replacement = %.0f\n", iOld, iNew
endin
</CsInstruments>
<CsScore>
f 1 0 -5 -2 0 0 0 0 0
f 2 0 -5 -2 0 0 0 0 0
i 1 0 0.01
e
</CsScore>
</CsoundSynthesizer>

See also

tablew, ptablew, tableiw

Credits

Author John ffitch, based on work by Robin Whittle, February 2012.