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creating random numbers
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Hi.
If I want to generate random numbers between -1 and 1, do I need to write a function to do that or is their something in the stdlib that can do it?
Thanks.
If I want to generate random numbers between -1 and 1, do I need to write a function to do that or is their something in the stdlib that can do it?
Thanks.
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Join Date: Aug 2005
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>>If I want to generate random numbers between -1 and 1
Why? The only number between -1 and 1 is 0. -1, 0 and 1 are all integers, there are no fractions in integer math. rand() returns an integer. So if you want a float return value, such as 0.123 then you will have to write a function that puts the return value from rand() into a float variable then divide it by RAND_MAX (defined in stdlib.h) to make it less than 1. I'm not sure how to make a random number between -1.0 and 0 other than just simply arbitrarily make the result from the above calculations negative.
Why? The only number between -1 and 1 is 0. -1, 0 and 1 are all integers, there are no fractions in integer math. rand() returns an integer. So if you want a float return value, such as 0.123 then you will have to write a function that puts the return value from rand() into a float variable then divide it by RAND_MAX (defined in stdlib.h) to make it less than 1. I'm not sure how to make a random number between -1.0 and 0 other than just simply arbitrarily make the result from the above calculations negative.
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Originally Posted by puppy
If I want to generate random numbers between -1 and 1, do I need to write a function to do that or is their something in the stdlib that can do it?
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