FutureBasic rnd function
Syntax
`randomInteger = rnd(expr)`

Description
This function returns a pseudo-random long integer uniformly distributed in the range 1 through expr. The expr parameter should be greater than 1, and must not exceed 65536. If the value returned is to be assigned to a 16-bit integer (randomInteger>), expr should not exceed 32767. The actual sequence of numbers returned by rnd depends on the random number generator's "seed" value; see the random statement for more information. Note that `rnd(1)` always returns the value 1.

Example
To get a random integer between two arbitrary limits min and max, use this statement:

`randomInteger = rnd(max - min + 1) + min - 1`

(Note `max - min` must be less than or equal to 65536.)

To get a random fraction, greater than or equal to zero and less than 1, use this statement:

`frac! = (rnd(65536)-1)/65536.0`

To get a random long integer in the range 1 through 2,147,483,647, use this statement:

`randomInteger = ((rnd(65536) - 1)<<15) + rnd(32767)`