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generating random number in range

Bilal Ali
Ranch Hand

Joined: Jun 14, 2007
Posts: 66
I am trying to write a very simple program that will generate a random number from 65 to 90(betwen 65 and 90) , I dont want to use the Random class or nextInt() method , i simply want to achieve this by using the Math.random() , can some one please help or give some suggestion.
Ulf Dittmer

Joined: Mar 22, 2005
Posts: 42965
random() returns a number between 0.0 and 1.0. You will need to scale this, and shift the result to an appropriate range. So the way to do this would be:

double scale = ???;
double shift = ???;

double rand = Math.random() * scale + shift;

What would appropriate values for scale and shift be?

As an aside, using the Random class might be simpler, since it can return an integer, and has a method that takes care of the scaling built in.
[ February 22, 2008: Message edited by: Ulf Dittmer ]
I agree. Here's the link:
subject: generating random number in range
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