Random Number from 0 to X

Posted on 2006-07-05
Last Modified: 2010-04-01
I need a random number generator that will give me a different number each time it is executed. The purpose of this is to insert random FLOAT numbers into an array.
Question by:strickdd
  • 2
LVL 17

Accepted Solution

rstaveley earned 500 total points
ID: 17043402

Expert Comment

ID: 17043526
Hi there,

//** a = [0...1[  
double a = (double)(rand()%RAND_MAX) / RAND_MAX

will generate pseudo random floating point values between 0 and 0.999...
There are better random number generators than the standard c implentation.

Get back if you have higher demands on the randomness.



Expert Comment

ID: 17043554
one addition:

The rand() function wll provide the same sequence of random integer values [0...RANDMAX] whenever your application restarts.
Use srand((unisnged int) time());
to intialize ('seed') the random number sequence.


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