problem with rand()

alisina-s · January 4, 2015, 14:06

Hi Everybody
I am using rand function in my solver and somehow I need random numbers between 0 and 6 but the problem is that when I simply use rand() function, I get unexpected huge numbers and these numbers are constant run by run.
I have read somewhere in forum that rand(an integer) should work.but in my case I have error.
can anyone help me with this?
thanks in advance

mprinkey · January 4, 2015, 14:36

rand() returns an int, so you need to normalize by RAND_MAX and convert to float/double if necessary. And if you don't use srand() to seed the PRNG, you will always get the same sequence.

http://eternallyconfuzzled.com/arts/jsw_art_rand.aspx

alisina-s · January 7, 2015, 10:08

thanks Micheal
now it is working fine

January 4, 2015, 14:06	problem with rand()	#1
alisina-s New Member Join Date: Mar 2014 Posts: 21 Rep Power: 12	Hi Everybody I am using rand function in my solver and somehow I need random numbers between 0 and 6 but the problem is that when I simply use rand() function, I get unexpected huge numbers and these numbers are constant run by run. I have read somewhere in forum that rand(an integer) should work.but in my case I have error. can anyone help me with this? thanks in advance

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January 4, 2015, 14:36		#2
mprinkey Senior Member Michael Prinkey Join Date: Mar 2009 Location: Pittsburgh PA Posts: 363 Rep Power: 25	rand() returns an int, so you need to normalize by RAND_MAX and convert to float/double if necessary. And if you don't use srand() to seed the PRNG, you will always get the same sequence. http://eternallyconfuzzled.com/arts/jsw_art_rand.aspx

January 7, 2015, 10:08		#3
alisina-s New Member Join Date: Mar 2014 Posts: 21 Rep Power: 12	thanks Micheal now it is working fine