newlib/winsup/mingw/mingwex/complex/casin.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

49 lines
900 B
C

/*
casin.c
Contributed by Danny Smith
2003-10-20
*/
#include <math.h>
#include <complex.h>
/* casin (Z ) = -I * clog(I * Z + csqrt (1.0 - Z * Z))) */
double complex casin (double complex Z)
{
double complex Res;
double x, y;
x = __real__ Z;
y = __imag__ Z;
if (y == 0.0)
{
__real__ Res = asin (x);
__imag__ Res = 0.0;
}
else /* -I * clog(I * Z + csqrt(1.0 - Z * Z))) */
{
double complex ZZ;
/* Z * Z = ((x - y) * (x + y)) + (2.0 * x * y) * I */
/* calculate 1 - Z * Z */
__real__ ZZ = 1.0 - (x - y) * (x + y);
__imag__ ZZ = -2.0 * x * y;
ZZ = csqrt (ZZ);
/* add I * Z to ZZ */
__real__ ZZ -= y;
__imag__ ZZ += x;
ZZ = clog (ZZ);
/* mult by -I */
__real__ Res = __imag__ ZZ;
__imag__ Res = - __real__ ZZ;
}
return (Res);
}