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| author | Joe Hunkeler <jhunkeler@gmail.com> | 2015-08-11 16:51:37 -0400 |
|---|---|---|
| committer | Joe Hunkeler <jhunkeler@gmail.com> | 2015-08-11 16:51:37 -0400 |
| commit | 40e5a5811c6ffce9b0974e93cdd927cbcf60c157 (patch) | |
| tree | 4464880c571602d54f6ae114729bf62a89518057 /unix/f2c/libf2c/z_sqrt.c | |
| download | iraf-osx-40e5a5811c6ffce9b0974e93cdd927cbcf60c157.tar.gz | |
Repatch (from linux) of OSX IRAF
Diffstat (limited to 'unix/f2c/libf2c/z_sqrt.c')
| -rw-r--r-- | unix/f2c/libf2c/z_sqrt.c | 35 |
1 files changed, 35 insertions, 0 deletions
diff --git a/unix/f2c/libf2c/z_sqrt.c b/unix/f2c/libf2c/z_sqrt.c new file mode 100644 index 00000000..35bd44c8 --- /dev/null +++ b/unix/f2c/libf2c/z_sqrt.c @@ -0,0 +1,35 @@ +#include "f2c.h" + +#ifdef KR_headers +double sqrt(), f__cabs(); +VOID z_sqrt(r, z) doublecomplex *r, *z; +#else +#undef abs +#include "math.h" +#ifdef __cplusplus +extern "C" { +#endif +extern double f__cabs(double, double); +void z_sqrt(doublecomplex *r, doublecomplex *z) +#endif +{ + double mag, zi = z->i, zr = z->r; + + if( (mag = f__cabs(zr, zi)) == 0.) + r->r = r->i = 0.; + else if(zr > 0) + { + r->r = sqrt(0.5 * (mag + zr) ); + r->i = zi / r->r / 2; + } + else + { + r->i = sqrt(0.5 * (mag - zr) ); + if(zi < 0) + r->i = - r->i; + r->r = zi / r->i / 2; + } + } +#ifdef __cplusplus +} +#endif |