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signum

Returns the signum of x returning -1, 0 or 1.

Syntax

signum(x) (no rate restriction)

Examples

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

Example of the signum opcode.
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<CsoundSynthesizer>
<CsOptions>
; Select audio/midi flags here according to platform
-odac     ;;;realtime audio out
;-iadc    ;;;uncomment -iadc if realtime audio input is needed too
; For Non-realtime ouput leave only the line below:
; -o signum.wav -W ;;; for file output any platform
</CsOptions>
<CsInstruments>

; by tgrey - 2020

sr     =    44100
ksmps  =    10
nchnls =    2
0dbfs  =    1

instr 1
        iinput = p4
        isignum = signum(iinput)
        print iinput
        print isignum
endin

</CsInstruments>
<CsScore>
i1 0 .1 100
i1 + . 50
i1 + . .25
i1 + . 0
i1 + . -.25
i1 + . -50
i1 + . -100
</CsScore>
</CsoundSynthesizer>

Here is another example of the signum opcode. It uses the file signum2.csd.

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<CsoundSynthesizer>
<CsOptions>
; Select audio/midi flags here according to platform
-odac     ;;;realtime audio out
;-iadc    ;;;uncomment -iadc if realtime audio input is needed too
; For Non-realtime ouput leave only the line below:
; -o signum2.wav -W ;;; for file output any platform
</CsOptions>
<CsInstruments>

sr     =    44100
kr     =    4410
ksmps  =    10
nchnls =    2
0dbfs  =    1

gaArr[]  init  2

instr 1
kEnv transeg    1, p3, -3, 0

a_pi = 4 * taninv(1.0);
a1   phasor 440;
a2   = sin(2 * a_pi * 1/ksmps * a1);
a3   dcblock2 a2
asig = signum(a3)

gaArr[0] = a2   * 0.6 * kEnv 
gaArr[1] = asig * 0.6 * kEnv 

outs  gaArr[0], gaArr[1]
endin

</CsInstruments>
<CsScore>
i 1 0 3

</CsScore>
</CsoundSynthesizer>

A musical example featuring the signum opcode: Signum_Welsh.csd by Kevin Welsh.

See also

Trigonometric Functions

Credits

Author: John ffitch
University of Bath, Codemist Ltd.
Bath, UK
July 2013

New in Csound version 6.01