[gameprogrammer] Re: Random Integer Problem :(

Perhaps you can explain why the modulus would be the improper way of getting
a random number?

On 9/24/06, Olivier Delannoy <olivier.delannoy@xxxxxxxxx> wrote: 

       In  Numerical Recipes in C: The Art of Scientific Computing
(William H.
       Press, Brian P. Flannery, Saul A. Teukolsky, William T. Vetterling;
New
       York:  Cambridge University Press, 1992 (2nd ed., p. 277)), the
follow-
       ing comments are made:

              "If you want to generate a random integer between 1 and
10,  you
              should always do it by using high-order bits, as in

                     j = 1 + (int) (10.0 * (rand() / (RAND_MAX + 1.0)));

              and never by anything resembling

                     j = 1 + (rand() % 10);


from unix man page of rand
$> man 3 rand

On 9/24/06, Chris Nystrom <cnystrom@xxxxxxxxx> wrote:
>
>
> On 9/23/06, Sahan Chandrasekara <sahanthegamecreator@xxxxxxxxx> wrote:
> > Hi,
> >
> > I'm trying to use this code to generate a random number between 1 and
six
> inclusive:
> >
> >
> > int random_int() {
> >     srand(time(NULL));
> >     int random_num=rand()%7;
> >     return random_num;
> > }
> >
> > But it dosen't work. My program is programmed to quit immediantly if
the
> number is not between 1 and six inclusive, and that is what it does
>
> I believe for 1-6 you want something like:
>
> random_num = ((rand() % 6) + 1);
>
> Chris
>
> --
> E-Mail: Chris Nystrom <cnystrom@xxxxxxxxx >
> http://www.newio.org/
> AIM: nystromchris


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--
./Andrew

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