r_sign.c

SuperLU is a general purpose library for the direct solution of large, sparse, nonsymmetric systems

#include "f2c.h"

#ifdef KR_headers
double r_sign(a,b) real *a, *b;
#else
double r_sign(real *a, real *b)
#endif
{
double x;
x = (*a >= 0 ? *a : - *a);
return( *b >= 0 ? x : -x);
}