Thread: How to generate a random number in the interval of -1 and 1?

Originally Posted by hamster_nz

There is one more number between 1.0-DBL_EPSILON and 1.0

Ahhh... of course, since we change the scale from 2⁰ to 2⁻¹! Nice catch.

Me? I would most likely do what I did when I needed random numbers that were inside a sphere. Generate random numbers between -1 and 1 (inclusive), and if it s >= 1.0 or <= -1.0 then just loop and try again.... so

Code:

    do {
       x = (double)rand()/RAND_MAX*2.0-1.0;
   while(x <= -1.0 || x >= 1.0);

Guys, I am sorry to be late to deliver THANKS to everyone. Appreciated so much that I have learned from your code. Thanks again.