randh
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## randh

randh — Generates random numbers and holds them for a period of time.

## Description

Generates random numbers and holds them for a period of time.

## Syntax

    ares randh xamp, xcps [, iseed] [, isize] [, ioffset]

    kres randh kamp, kcps [, iseed] [, isize] [, ioffset]

## Initialization

iseed (optional, default=0.5) -- seed value for the recursive pseudo-random formula. A value between 0 and +1 will produce an initial output of kamp * iseed. A negative value will cause seed re-initialization to be skipped. A value greater than 1 will seed from system time, this is the best option to generate a different random sequence for each run.

isize (optional, default=0) -- if zero, a 16 bit number is generated. If non-zero, a 31-bit random number is generated. Default is 0.

ioffset (optional, default=0) -- a base value added to the random result. New in Csound version 4.03.

## Performance

kamp, xamp -- range over which random numbers are distributed.

kcps, xcps -- the frequency which new random numbers are generated.

The internal pseudo-random formula produces values which are uniformly distributed over the range -kamp to +kamp. rand will thus generate uniform white noise with an R.M.S value of kamp / root 2.

The remaining units produce band-limited noise: the kcps and xcps parameters permit the user to specify that new random numbers are to be generated at a rate less than the sampling or control frequencies. randh will hold each new number for the period of the specified cycle.

## Examples

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

Example 424. Example of the randh 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
    ; Audio out   Audio in
    -odac           -iadc    ;;;RT audio I/O
    ; For Non-realtime ouput leave only the line below:
    ; -o randh.wav -W ;;; for file output any platform
    </CsOptions>
    <CsInstruments>

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

    ; Instrument #1.
    instr 1
      ; Choose a random frequency between 200 and 1000.
      ; Generate new random numbers at 4 Hz.
      ; kamp = 400
      ; kcps = 4
      ; iseed = 0.5
      ; isize = 0
      ; ioffset = 600

      kcps randh 400, 4, 0.5, 0, 600
      printk2 kcps

      a1 oscil 30000, kcps, 1
      out a1
    endin

    </CsInstruments>
    <CsScore>

    ; Table #1, a sine wave.
    f 1 0 16384 10 1

    ; Play Instrument #1 for one second.
    i 1 0 5
    e

    </CsScore>
    </CsoundSynthesizer>

## See Also

rand, randi

## Credits

Example written by Kevin Conder.

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