Returns x with the same sign as y.
    This function is OpenVMS Alpha and Integrity servers only.
    Format
      #include  <math.h>
      double copysign  (double x, double y);
      float copysignf  (float x, float y);
                       (Integrity servers, Alpha)
      long double copysignl  (long double x, long double y);
                             (Integrity servers, Alpha)
Additional Information:
explode
extract