/usr/share/SuperCollider/HelpSource/Classes/IndexL.schelp is in supercollider-common 1:3.8.0~repack-2.
This file is owned by root:root, with mode 0o644.
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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89  | class:: IndexL
summary:: Index into a table with a signal, linear interpolated
categories:: UGens>Buffer
related:: Classes/Index, Classes/IndexInBetween
description::
The input signal value is used as an index into the table, with linear interpolation.
Out of range index values are clipped to the valid range.
classmethods::
method:: ar, kr
argument:: bufnum
index of the buffer.
argument:: in
the input signal.
examples::
code::
// indexing into a fixed table
(
{
	SinOsc.ar(
		IndexL.kr(
			LocalBuf.newFrom([ 200, 300, 400, 500, 600, 800 ].scramble),
			LFSaw.kr(2.0).range(0, 7)
		),
		0,
		0.5
	)
}.play;
)
// with mouse control
(
{
	SinOsc.ar(
		IndexL.kr(
			LocalBuf.newFrom([ 200, 300, 400, 500, 600, 800 ].scramble),
			MouseX.kr(0, 7)
		),
		0,
		0.5
	)
}.play;
)
(
// indexing into a changeable table
s = Server.local;
t = [ 200, 300, 400, 500, 600, 800 ];
b = Buffer(s, t.size, 1);
// alloc and set the values
s.listSendMsg( b.allocMsg( b.setnMsg(0, t) ).postln );
SynthDef(\help_index, { arg out = 0, i_bufnum = 0;
	Out.ar(0,
		SinOsc.ar(
			IndexL.kr(
				i_bufnum,
				LFSaw.kr(2).range(0, 7)
			),
			0,
			0.5
		)
	)
}).play(s, [\i_bufnum, b]);
)
b.setn(*[ 200, 300, 400, 500, 600, 800 ].scramble.postln - 30);
(
SynthDef(\help_index, { arg out = 0, i_bufnum = 0;
	Out.ar(0,
		SinOsc.ar(
			IndexL.kr(
				i_bufnum,
				MouseX.kr(0, BufFrames.ir(i_bufnum))
			),
			0,
			0.5
		)
	)
}).play(s, [\i_bufnum, b]);
)
b.free;
::
 |