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# poisson

poisson -- Poisson distribution random number generator (positive values only).

## Description

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

## Syntax

ar poisson klambda

ir poisson klambda

kr poisson klambda

## Performance

klambda -- the mean of the distribution. Outputs only positive numbers.

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 poisson opcode. It uses the files poisson.orc and poisson.sco.

Example 1. Example of the poisson opcode.

    /* poisson.orc */
    ; Initialize the global variables.
    sr = 44100
    kr = 4410
    ksmps = 10
    nchnls = 1

    ; Instrument #1.
    instr 1
      ; Generates a random number in a poisson distribution.
      ; klambda = 1

      i1 poisson 1

      print i1
    endin
    /* poisson.orc */

    /* poisson.sco */
    ; Play Instrument #1 for one second.
    i 1 0 1
    e
    /* poisson.sco */

Its output should include a line like this:

    instr 1:  i1 = 1.000

## See Also

betarand, bexprnd, cauchy, exprand, gauss, linrand, pcauchy, trirand, unirand, weibull

## Credits

Author: Paris Smaragdis
MIT, Cambridge
1995

Example written by Kevin Conder.

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