y Statement (or Seed Statement)

a — Set seed for random numbers.

Description

Set seed for random numbers, either from p1 or, if omitted, the clock.

Syntax

y [p1]

Initialization

p1 -- An integer value between 0 and 232 used as a new seed for random numbers. If omitted, the system clock value will be used instead.

Performance

The tilde symbol ˜ can be used in an expression wherever a number is permissible to use. Each ˜ will evaluate to a random value between zero (0) and one (1). If there is no y statement in the score, the pseudo-random generator will yield the same numbers in each performance. If a fixed seed is given, a different predictable series of pseudo-random numbers will be generated from this seed. If a y statement is used without p1, the system clock will be used as a seed, yielding a different series of pseudo-random numbers for each performance.

Examples

Here is an example of the y statement. It uses the file y_statement.csd.

Example 1124. Example of the y statement.

<CsoundSynthesizer>
<CsOptions>
; Select audio/midi flags here according to platform
; Audio out   Audio in    No messages
-odac           -iadc     -d     ;;;RT audio I/O
; For Non-realtime ouput leave only the line below:
; -o 0dbfs.wav -W ;;; for file output any platform
</CsOptions>
<CsInstruments>

; Initialize the global variables.
sr = 44100
ksmps = 10
nchnls = 2
0dbfs = 1

instr 1
  print p4
endin
</CsInstruments>
<CsScore>

y

i 1 0 1 [~ * 9 + 1]
i 1 + 1 [~ * 9 + 1]
i 1 + 1 [~ * 9 + 1]
i 1 + 1 [~ * 9 + 1]
e

</CsScore>
</CsoundSynthesizer>


Each time this example is run, different values between 1 and 10 will be displayed. The seed used will be displayed as well.

Credits

Author: John ffitch, 2014

New in version 6.03