result = RndF()
RndF() can be set using the RndSeed() function.
Note that before Hollywood 8.0 this function's upper boundary was documented as 1.0 (inclusive).
This was wrong. The value returned by RndF() is guaranteed to be less than 1.0.
num = RndF()
num is set to random floating point number between 0.0 and 1.0.