newlib/winsup/mingw/mingwex/complex/csqrt.c
Danny Smith 3c7a7a5fca Add ISO C99 complex support for doubles.
* include/complex.h: New file.
	* mingwex/complex: New directory.
	* mingwex/complex/cabs.c: New file.
	* mingwex/complex/cacos.c: New file.
	* mingwex/complex/cacosh.c: New file.
	* mingwex/complex/casin.c: New file.
	* mingwex/complex/casinh.c: New file.
	* mingwex/complex/catan.c: New file.
	* mingwex/complex/catanh.c: New file.
	* mingwex/complex/ccos.c: New file.
	* mingwex/complex/ccosh.c: New file.
	* mingwex/complex/cexp.c: New file.
	* mingwex/complex/cimag.c: New file.
	* mingwex/complex/clog.c: New file.
	* mingwex/complex/cpow.c: New file.
	* mingwex/complex/cproj.c: New file.
	* mingwex/complex/creal.c: New file.
	* mingwex/complex/csin.c: New file.
	* mingwex/complex/csinh.c: New file.
	* mingwex/complex/csqrt.c: New file.
	* mingwex/complex/ctan.c: New file.
	* mingwex/complex/ctanh.c: New file.
	* mingwex/Makefile.in (COMPLEX_DISTFILES): New list of
	files.
	(dist): Use it.
	(COMPLEX_OBJS): New list of objects.
	(LIB_OBJS): Include it in the library.
2003-10-21 09:43:22 +00:00

56 lines
867 B
C

/*
csqrt.c
Contributed by Danny Smith
2003-10-20
*/
#include <math.h>
#include <complex.h>
double complex csqrt (double complex Z)
{
double complex Res;
double t;
double x = __real__ Z;
double y = __imag__ Z;
if (y == 0.0)
{
if (x < 0.0)
{
__real__ Res = 0.0;
__imag__ Res = sqrt (-x);
}
else
{
__real__ Res = sqrt (x);
__imag__ Res = 0.0;
}
}
else if (x == 0.0)
{
t = sqrt(0.5 * fabs (y));
__real__ Res = y > 0 ? t : -t;
__imag__ Res = t;
}
else
{
t = sqrt (2.0 * (_hypot (x, y) + fabs (x)));
if ( x > 0.0)
{
__real__ Res = 0.5 * t;
__imag__ Res = y / t;
}
else
{
__real__ Res = fabs ( y / t);
__imag__ Res = (y < 0.0 ? -0.5 : 0.5) * t;
}
}
return Res;
}