libf2c/libF77/cabs.c

   1 #ifdef KR_headers
   2 extern double sqrt();
   3 double f__cabs(real, imag) double real, imag;
   4 #else
   5 #undef abs
   6 #include <math.h>
   7 double f__cabs(double real, double imag)
   8 #endif
   9 {
  10 double temp;
  11
  12 if(real < 0)
  13         real = -real;
  14 if(imag < 0)
  15         imag = -imag;
  16 if(imag > real){
  17         temp = real;
  18         real = imag;
  19         imag = temp;
  20 }
  21 if((real+imag) == real)
  22         return(real);
  23
  24 temp = imag/real;
  25 temp = real*sqrt(1.0 + temp*temp);  /*overflow!!*/
  26 return(temp);
  27 }