JG>   int a,b,;
JG>   double u,z;
JG>   z = (double) a/b;
JG>   /* what's the purpose of the "()" on double here? */
JG>   u = (double) (a/b);
JG>   /* what's the purpose of the 2 "()" here? */
   a and b are integer values. In order to preserve the decimal
   portion of the quotient, you need to explicitly cast it to
   type. Otherwise, the remainder will be lost.
   If you want to see the difference it makes, then run an
   example program. In the first instance, a will be cast to
   double, but not b, and in the second, the quotient will be
   cast to double.
#include 
int main(void)
{
   int a, b;
   printf("(double)a/b = %f\n", (double)a / b);
   printf("(double)(a/b) = %f\n", (double)(a / b));
   return 0;
}

> ] "Does that motor sound funny to you?"  :  Buddy Holly.......

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