Description

Generates random numbers with a user-defined limit and holds them for a period of time.

Syntax

ares randomh kmin, kmax, xcps [,imode] [,ifirstval]

kres randomh kmin, kmax, kcps [,imode] [,ifirstval]

Initialization

imode (optional, default=0) -- generation mode of the first output value (see below)

ifirstval (optional, default=0) -- first output value

Performance

kmin -- minimum range limit

kmax -- maximum range limit

kcps, xcps -- rate of random break-point generation

The randomh opcode is similar to randh but allows the user to set arbitrary minimum and maximum values.

When imode = 0 (the default), the kmin argument value is outputted during 1/kcps (resp. 1/xcps) seconds at the beginning of the note. Then, the normal process takes place with a new random number generated and held every 1/kcps (resp. 1/xcps) seconds.

When imode = 2, the ifirstval argument value is outputted during 1/kcps (resp. 1/xcps) seconds at the beginning of the note. Then, the normal process takes place with a new random number generated and held every 1/kcps (resp. 1/xcps) seconds.

When imode = 3, the generation process begins with a random value from the initialization time.

Examples

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

<CsoundSynthesizer>
<CsOptions>
; Select audio/midi flags here according to platform
; Audio out   Audio in
-odac           -iadc    ;;;RT audio I/O
; For Non-realtime ouput leave only the line below:
; -o randomh.wav -W ;;; for file output any platform
</CsOptions>
<CsInstruments>

; Initialize the global variables.
sr = 44100
kr = 4410
ksmps = 10
nchnls = 1

     seed 0
     
; Instrument #1.
instr 1
  ; Choose a random frequency between 220 and 440 Hz.
  ; Generate new random numbers at 10 Hz.
  kmin    init 220
  kmax    init 440
  kcps    init 10
  imode   =    p4
  ifstval =    p5
  
     printf_i "\nMode: %d\n", 1, imode
  k1 randomh kmin, kmax, kcps, imode, ifstval
     printk2 k1
endin

</CsInstruments>
<CsScore>

; Play Instrument #1 for one second,
; each time with a different mode.
i 1 0 1
i 1 1 1 2 330
i 1 2 1 3
e

</CsScore>
</CsoundSynthesizer>

Its output should include lines like this:

Mode: 0
 i1   220.00000
 i1   396.26079
 i1   240.75446
 i1   364.24577
    ...

Mode: 2
 i1   330.00000
 i1   416.50935
 i1   356.11619
 i1   433.59324
    ...

Mode: 3
 i1   261.17741
 i1   402.00891
 i1   393.86592
 i1   307.19839
    ...

See Also

randh, random, randomi

Credits

Author: Gabriel Maldonado

Arguments imode and ifirstval added by François Pinot, Jan. 2011, after a discussion with Peiman Khosravi on the csnd list.

Example written by Kevin Conder, adapted for new args by François Pinot.