libf2c/libF77/r_mod.c

   1 #include "f2c.h"
   2
   3 #ifdef IEEE_drem
   4 double drem (double, double);
   5 #else
   6 #undef abs
   7 #include <math.h>
   8 #endif
   9 double
  10 r_mod (real * x, real * y)
  11 {
  12 #ifdef IEEE_drem
  13   double xa, ya, z;
  14   if ((ya = *y) < 0.)
  15     ya = -ya;
  16   z = drem (xa = *x, ya);
  17   if (xa > 0)
  18     {
  19       if (z < 0)
  20         z += ya;
  21     }
  22   else if (z > 0)
  23     z -= ya;
  24   return z;
  25 #else
  26   double quotient;
  27   if ((quotient = (double) *x / *y) >= 0)
  28     quotient = floor (quotient);
  29   else
  30     quotient = -floor (-quotient);
  31   return (*x - (*y) * quotient);
  32 #endif
  33 }