pcauchy
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## pcauchy

pcauchy — Cauchy distribution random number generator (positive values only).

## Description

Cauchy distribution random number generator (positive values only). This is an x-class noise generator.

## Syntax

    ares pcauchy kalpha

    ires pcauchy kalpha

    kres pcauchy kalpha

## Performance

pcauchy kalpha -- controls the spread from zero (big kalpha = big spread). Outputs positive numbers only.

For more detailed explanation of these distributions, see:

1. C. Dodge - T.A. Jerse 1985. Computer music. Schirmer books. pp.265 - 286

2. D. Lorrain. A panoply of stochastic cannons. In C. Roads, ed. 1989. Music machine . Cambridge, Massachusetts: MIT press, pp. 351 - 379.

## Examples

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

Example 742. Example of the pcauchy opcode.

See the sections Real-time Audio and Command Line Flags for more information on using command line flags.

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

    sr = 44100
    ksmps = 32
    nchnls = 2
    0dbfs  = 1

    instr 1  	; every run time same values

    kalpha	pcauchy	1000
    	printk	.2, kalpha		; look
    aout	oscili	0.8, 440+kalpha, 1	; & listen
    	outs	aout, aout
    endin

    instr 2		; every run time different values

    	seed 0
    kalpha	pcauchy	1000
    	printk	.2, kalpha		; look
    aout	oscili	0.8, 440+kalpha, 1	; & listen
    	outs	aout, aout
    endin
    </CsInstruments>
    <CsScore>
    ; sine wave
    f 1 0 16384 10 1

    i 1 0 2
    i 2 3 2
    e

    </CsScore>
    </CsoundSynthesizer>

Its output should include a line like this:

     i   1 time     0.00033:    10.48851
     i   1 time     0.20033:     0.29508
     i   1 time     0.40033:     1.75214
     i   1 time     0.60033:    22.88281
     i   1 time     0.80033:    16.06435
     i   1 time     1.00000:     0.43110
     i   1 time     1.20033:    16.51694
     i   1 time     1.40033:     2.98797
     i   1 time     1.60033:     1.32767
     i   1 time     1.80000:    17.94039
     i   1 time     2.00000:     4.85994
     Seeding from current time 1526147515
     i   2 time     3.00033:     0.89797
     i   2 time     3.20033:     9.19447
     i   2 time     3.40033:     0.73053
     i   2 time     3.60000:     7.43371
     i   2 time     3.80033:     5.87640
     i   2 time     4.00000:     0.80456
     i   2 time     4.20000:     4.50637
     i   2 time     4.40033:     2.08145
     i   2 time     4.60033:    13.47125
     i   2 time     4.80033:     3.16399
     i   2 time     5.00000:    11.05428

## See also

Random (Noise) Generators

## Credits

Author: Paris Smaragdis
MIT, Cambridge
1995

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