rsc3/doc-schelp/HelpSource/Classes/BinaryOpUGen.schelp

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class:: BinaryOpUGen
summary:: Apply a binary operation to the values of an input UGen
related:: Classes/UnaryOpUGen, Classes/BinaryOpFunction, Classes/Pbinop, Overviews/Operators
categories:: UGens>Algebraic
description::
BinaryOpUGens are created as the result of a binary operator applied to a link::Classes/UGen::.
code::
(SinOsc.ar(200) * ClipNoise.ar).dump;
(SinOsc.ar(200).thresh(0.5)).dump;
::
The use of the binary operators code::*:: and code::thresh:: above each instantiate a BinaryOpUGen. The operators themselves (which are methods) are not to be confused with the resulting BinaryOpUGen (which is an object). The unary and binary operators are defined in link::Classes/UGen::'s superclass link::Classes/AbstractFunction::, which creates the
BinaryOpUGen as a result of the operation.
When operating on UGens instead of numbers, what results is not a result of the calculation, but a structure that represents that calculation. For the immediate operations on numbers, see for example link::Classes/SimpleNumber::.
See link::Overviews/Operators:: for an overview of common operators.
classmethods::
private:: new1
method::new
return a new instance that applies the operator code::selector:: to the UGens code::a:: and code::b:: normally, this is implicitly called when applying an operator to a link::Classes/UGen::.
argument:: selector
The selector symbol for the binary operator
argument:: a
left operand
argument:: b
right operand
returns:: A new instance of BinaryOpUGen
instancemethods::
private:: init, optimizeGraph, constantFolding
examples::
code::
a = WhiteNoise.ar; // a WhiteNoise
b = a + 2; // a BinaryOpUGen.
b.operator; // +
// sound example
(
{
var a = LFSaw.ar(300);
var b = LFSaw.ar(329.1);
a % b * 0.1
}.play;
)
::
subsection::The comparison operators
The operators code:: >, >=, <, <= :: are particularly useful for triggering. They should not be confused with their use in conditionals. Compare:
code::
if(1 > 0) { "1 is greater than 0".postln }; // > returns a boolean
::
with
code::
// trigger an envelope
(
{
var trig;
trig = SinOsc.ar(1) > 0.1;
EnvGen.kr(Env.perc, trig, doneAction: Done.none) * SinOsc.ar(440,0,0.1)
}.play
) // > outputs 0 or 1
::
See link::Overviews/Operators:: or the implementation of these in link::Classes/AbstractFunction:: for more detail.
Since the equality operator ( code::==:: ) is used to distinguish objects including UGens, it cannot be used to create a BinaryOpUGen by application. Instead, to get a trigger value each time two signals are the same (instead of just finding out whether two UGens are the same), one can instantiate a BinaryOpUGen directly:
code::
(
{
var a = SinOsc.ar(1).round(0.1);
var b = SinOsc.ar(1.2).round(0.1);
BinaryOpUGen('==', a, b) * 0.1
}.play;
)
::