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 value greater than 1 will be used directly, without scaling. A negative value will cause seed re-initialization to be skipped. The default seed value is .5.
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.
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.
Here is an example of the rand opcode. It uses the files rand.orc and rand.sco.
Example 1. Example of the rand opcode.
/* rand.orc */
/* Written by Kevin Conder */
; Initialize the global variables.
sr = 44100
kr = 4410
ksmps = 10
nchnls = 1
; Instrument #1.
instr 1
; Choose a random frequency between 4,100 and 44,100.
kfreq rand 40000
kcps = kfreq + 4100
a1 oscil 30000, kcps, 1
out a1
endin
/* rand.orc */
/* rand.sco */
/* Written by Kevin Conder */
; Table #1, a sine wave.
f 1 0 16384 10 1
; Play Instrument #1 for one second.
i 1 0 1
e
/* rand.sco */