RAND

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rand, randh, randi

     kr   rand      xamp[, iseed]
     kr   randh     kamp, kcps[, iseed]
     kr   randi     kamp, kcps[, iseed]
     ar   rand      xamp[, iseed]
     ar   randh     xamp, xcps[, iseed]
     ar   randi     xamp, xcps[, iseed]

DESCRIPTION

Output is a controlled random number series between +amp and -amp

INITIALIZATION

iseed (optional) - seed value for the recursive psuedo-random formula. A value between 0 and +1 will produce an initial output of kamp * iseedA negative value will cause seed re-initialization to be skipped. The default seed value is .5.

PERFORMANCE

The internal psuedo-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 cps 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; randi will produce straightline interpolation between each new number and the next.

EXAMPLE:

   i1   =      octpch(p5) ; center pitch, to be modified
   k1   randh  1,10       ;10 time/sec by random displacements up to 1 octave
   a1   oscil  5000, cpsoct(i1+k1), 1

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