tabrowlin
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## tabrowlin

tabrowlin — Copy a row from an f-table to another, interpolating between rows

## Description

Plugin opcode in beosc.

This opcode assumes the use of a table, which is a simple 1D array, to hold a 2D matrix with a given row length. Assuming such a 2D table containing multiple rows of sampled streams (for instance, the amplitudes of a set of oscilators, sampled at a regular interval), this opcode can extract one row (or a slice of a row) of that data with linear interpolation between adjacent rows (if row is not a whole number) and place the result in another table

## Syntax

    tabrowlin krow, ifnsrc, ifndest, inumcols [, ioffset, istart, iend, istep ]

## Initialization

ifnsrc: The table index to copy data from

ifndest: The table index to copy data to (should be able to hold one row of data)

inumcols: the number of columns a row has, in the source table

ioffset: an offset to where the 2D data starts (used to skip a header, if present) (default = 0)

istart: start index to read from (refers to the row) (default = 0)

iend: end index to read from the row (not inclusive, should not exceed inumcols)

istep: step used to read along the row (default = 1)

## Performance

krow -- the row to read. It can be a fractional number, in which case the row will be linearly interpolated with the next row

## Examples

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

Example 1043. Example of the tabrowlin opcode.

    <CsoundSynthesizer>
    <CsOptions>
    -odac     ;;;realtime audio out
    </CsOptions>
    <CsInstruments>

    /*

    This is the example file for tabrowlin

    tabrowlin
    =========

      This opcode assumes the use of a table, which is a simple 1D array,
      to hold a 2D matrix with a given row length.
      Assuming such a 2D table containing multiple rows of sampled streams
      (for instance, the amplitudes of a set of oscilators, sampled at a
      regular interval), this opcode can extract one row of that data with
      linear interpolation between adjacent rows (if row is not a whole number)
      and place the result in another table

    Syntax
    ======

    tabrowlin krow, ifnsrc, ifndest, inumcols, ioffset=0, istart=0, iend=0, istep=1

    krow     : the row to read (can be a fractional number, in which case interpolation
               with the next row is performed)
    ifnsrc   : index of the source table
    ifndest  : index of the dest table
    inumcols : the number of columns a row has, in the source table
    ioffset  : an offset to where the data starts (used to skip a header, if present)
    istart   : start index to read from the row (not the start index of the table)
    iend     : end index to read from the row (not inclusive)
    istep    : step used to read the along the row

    If reading out of bounds a PerformanceError will be raised. Because we
    interpolate between rows, the last row that can be read is

      maxrow = (ftlen(ifnsrc)-ioffset)/inumcols - 2

    */

    sr = 44100
    ksmps = 128
    nchnls = 1
    0dbfs  = 1

    instr 1
      ; just a simple test of the bare functionality
      ; generate a 4x3 table
      isource ftgentmp 0, 0, -12, -2, \
           0,  1,  2,  3,   \
          10, 11, 12, 13,   \
          20, 21, 22, 23
      ; create an empty table able to hold one row (4 elements)
      idest ftgentmp 0, 0, -4, -2, 0
      print ftlen(isource)
      ; we exceed the max. row to show what happens (the row is clipped
      ; to the max row possible and a message is printed to show the error)
      krow linseg 0, p3, 2.05
      printk2 krow, 20
      tabrowlin krow, isource, idest, 4
      ftprint idest, -1
    endin

    </CsInstruments>
    <CsScore>
    i 1 0 2
    </CsScore>
    </CsoundSynthesizer>

## See Also

getrowlin, ftslice, slicearray, copyf2array, tab2array, tablecopy, tableicopy,

## Credits

By: Eduardo Moguillansky 2018

New in version 6.12

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