| /** |
| * This file has no copyright assigned and is placed in the Public Domain. |
| * This file is part of the w64 mingw-runtime package. |
| * No warranty is given; refer to the file DISCLAIMER.PD within this package. |
| */ |
| /* |
| 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 = t; |
| __imag__ Res = y > 0 ? t : -t; |
| } |
| |
| else |
| { |
| t = sqrt (2.0 * (_hypot (x, y) + fabs (x))); |
| double u = t / 2.0; |
| if ( x > 0.0) |
| { |
| __real__ Res = u; |
| __imag__ Res = y / t; |
| } |
| else |
| { |
| __real__ Res = fabs ( y / t); |
| __imag__ Res = y < 0.0 ? -u : u; |
| } |
| } |
| |
| return Res; |
| } |
| |