Ns rand

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Man page: http://aolserver.com/docs/tcl/ns_rand.html


NAME

ns_rand - Generate a random number

SYNOPSIS

ns_rand ?maximum?

DESCRIPTION

This command generates a cryptographically secure random number. If maximum is not specified, the random number returned is a floating-point value n such that 0.0 <= n < 1.0. If maximum is specified, it must be a positive integer between 1 and 2147483647, in which case ns_rand will return an integer value n such that 0 <= n <= max - 1.
Internally ns_rand is implemented with the drand48() and lrand48() standard library functions. An internal random seed is generated the first time ns_rand is called after the server starts.

EXAMPLES

   % ns_rand
   0.39938485692
   % ns_rand 10
   7

CAVEAT

[ns_rand 1] will always produce the result 0. [ns_rand 2] will produce the desired "coin flip" outcome of 0 or 1. This is standard with Java's java.util.Random implementation of nextInt and most other random number libraries.

SEE ALSO