From 40e5a5811c6ffce9b0974e93cdd927cbcf60c157 Mon Sep 17 00:00:00 2001 From: Joe Hunkeler Date: Tue, 11 Aug 2015 16:51:37 -0400 Subject: Repatch (from linux) of OSX IRAF --- unix/f2c/libf2c/pow_zi.c | 60 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 60 insertions(+) create mode 100644 unix/f2c/libf2c/pow_zi.c (limited to 'unix/f2c/libf2c/pow_zi.c') diff --git a/unix/f2c/libf2c/pow_zi.c b/unix/f2c/libf2c/pow_zi.c new file mode 100644 index 00000000..1c0a4b07 --- /dev/null +++ b/unix/f2c/libf2c/pow_zi.c @@ -0,0 +1,60 @@ +#include "f2c.h" +#ifdef __cplusplus +extern "C" { +#endif + +#ifdef KR_headers +VOID pow_zi(p, a, b) /* p = a**b */ + doublecomplex *p, *a; integer *b; +#else +extern void z_div(doublecomplex*, doublecomplex*, doublecomplex*); +void pow_zi(doublecomplex *p, doublecomplex *a, integer *b) /* p = a**b */ +#endif +{ + integer n; + unsigned long u; + double t; + doublecomplex q, x; + static doublecomplex one = {1.0, 0.0}; + + n = *b; + q.r = 1; + q.i = 0; + + if(n == 0) + goto done; + if(n < 0) + { + n = -n; + z_div(&x, &one, a); + } + else + { + x.r = a->r; + x.i = a->i; + } + + for(u = n; ; ) + { + if(u & 01) + { + t = q.r * x.r - q.i * x.i; + q.i = q.r * x.i + q.i * x.r; + q.r = t; + } + if(u >>= 1) + { + t = x.r * x.r - x.i * x.i; + x.i = 2 * x.r * x.i; + x.r = t; + } + else + break; + } + done: + p->i = q.i; + p->r = q.r; + } +#ifdef __cplusplus +} +#endif -- cgit