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# Confusion in random() function

Shivani Prajapati
Greenhorn
Posts: 9
What will be the result of the expression ((int) (Math.random()*4))

Answer in khalid mughal book is � �expression will evaluate to one of the numbers 0,1,2 or 3.�
But how can it be possible?

Paras Jain
Ranch Hand
Posts: 140
Hi,
As per the API random function "Returns a double value with a positive sign, greater than or equal to 0.0 and less than 1.0. Returned values are chosen pseudorandomly with (approximately) uniform distribution from that range."
That means you will get something between 0 and 1(non-inclusive) like 0.1, 0.2,.03 .... 0.999. Any number within this range when multiplied by 4 wil give values between 0 to 4 like
.1*4 = .4 ,
.6*4 = 2.4 .....
.999*4 = 3.996.

Hope you got the point.
Thanks
Paras

Paras Jain
Ranch Hand
Posts: 140
And I forgot to mention that when these numbers will be casted to (int) the values after decimal will be lost
.1*4 = .4 which becomes 0,
.6*4 = 2.4 which becomes 2.....
.999*4 = 3.996 which becomes 3