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java - how do i get a random double within a specified range?

I really thought this would work, but when I ran it, I always get some random huge decimal and it makes no sense. The logic is right, so why doesn't the code work?

do{
  value = rnd.nextDouble();
}while(value>min && value<max);

Keep in mind "min" and "max" are actually functions that do some simple arithmetic operations then return that value, but I just put min and max for simplicity so I don't have to post the entire class.

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You can declare a start and end variables (int or double), and use nextDouble() like:

value = rnd.nextDouble() * (end - start) + start;

Remember that:

public double nextDouble() Returns the next pseudorandom, uniformly distributed double value between 0.0 and 1.0 from this random number generator's sequence.


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