is there any way to get random numbers in a user-definable range? the old RAND function will only return numbers between 0 and 0x7fff. i don''t want it to do that. i want to return numbers between 0 and some number the use types in. is there another random function i could use? or is there some way of mangling RAND()''s output to return a number in a certain range? thanks

The easiest, (yet somewhat innacurate to get even spread) way is

randnum=rand()%(highestnum-1)+lowestnum;

ie

randnum=rand()%9;

would output a num between 0 and 8.

thanks

You really shouldn''t use modulus (%) with rand in that way.
I can''t be bothered to go into the details on why, but there''s several other threads here on gamedev where it''s been discussed. Search for one of them.

-Neophyte

Well, ktuluorion''s method doesn''t work from what I can see . If you want to have a number between 3 and 8, for example, with his method you would get numbers between 3 and 10. If you want to do it modulo-style, it''d look like this:

randnum=rand()%(1+Highest-Lowest)+Lowest;

Still it''s not the best way to do things but I can''t find the thread where it was discussed right now as search is still disabled . Someone posted this in it, however, when I tried it out, it didn''t work iirc...

int rand_good (int N) { return( N * rand () / ((int)RAND_MAX + 1)); }

(It actually should work.. you''d just have to combine it with the above: rand_good(1+Highest-Lowest)+Lowest

double rand_01() { return (double)rand() / (double)RAND_MAX; )

long rand_n( long n ) { return (long)( n*rand_01() ); }

long rand_nm( long nmin, long nmax ) { return rand_n( nmax - nmin ) + nmin; }

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