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||

Logical OR operator.

Arithmetic operators perform operations of change-sign (negate), don't-change-sign, logical AND logical OR, add, subtract, multiply and divide. Note that a value or an expression may fall between two of these operators, either of which could take it as its left or right argument, as in

\[ a + b * c. \]

In such cases three rules apply:

  1. \(*\) and \(/\) bind to their neighbors more strongly than \(+\) and \(-\). Thus the above expression is taken as:
    \(a + (b * c)\) with \(*\) taking \(b\) and \(c\) and then \(+\) taking \(a\) and \(b * c\).

  2. \(+\) and \(-\) bind more strongly than &&, which in turn is stronger than ||:
    \(a \;\&\&\; b - c \;||\; d\) is taken as \((a \;\&\&\; (b - c))\;||\; d\)

  3. When both operators bind equally strongly, the operations are done left to right:
    \(a - b - c\) is taken as \((a - b) - c\)

Parentheses may be used as above to force particular groupings.

Syntax

a || b  (logical OR; not audio-rate)

where the arguments \(a\) and \(b\) may be further expressions.

Examples

Here is an example of the | operator. It uses the file logicOR.csd.

Example of the | operator.
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<CsoundSynthesizer>
<CsOptions>
; Select audio/midi flags here according to platform
-odac -+rtmidi=virtual -M0   ;;;realtime audio out and virtual midi keyboard
;-iadc    ;;;uncomment -iadc if realtime audio input is needed too
</CsOptions>
<CsInstruments>
;after a UDO from Rory Walsh
sr = 44100
ksmps = 32
nchnls = 2

instr 1 ;displays notes, midi channel and control number information

kstatus, kchan, kdata1, kdata2 midiin
k1 changed kstatus
k2 changed kchan
k3 changed kdata1
k4 changed kdata2
if((k1==1)||(k2==1)||(k3==1)||(k4==1)) then
printks "Value:%d ChanNo:%d CtrlNo:%d\n" , 0, kdata2, kchan, kdata1  
endif 

endin
</CsInstruments>
<CsScore>

i1  0  60       ;print values for 60 seconds

e
</CsScore>
</CsoundSynthesizer>

Its output should include a line like these:

Value:127 ChanNo:11 CtrlNo:62
Value:127 ChanNo:11 CtrlNo:60
Value:127 ChanNo:11 CtrlNo:60
Value:127 ChanNo:11 CtrlNo:60
Value:127 ChanNo:11 CtrlNo:60
....
Value:0 ChanNo:11 CtrlNo:62
Value:0 ChanNo:11 CtrlNo:62
Value:0 ChanNo:11 CtrlNo:62
Value:0 ChanNo:11 CtrlNo:62
....
Value:77 ChanNo:11 CtrlNo:23
Value:77 ChanNo:11 CtrlNo:23
Value:76 ChanNo:11 CtrlNo:23
Value:76 ChanNo:11 CtrlNo:23
....

See also

Arithmetic and Logic Operations