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authorJoseph Hunkeler <jhunkeler@gmail.com>2015-07-08 20:46:52 -0400
committerJoseph Hunkeler <jhunkeler@gmail.com>2015-07-08 20:46:52 -0400
commitfa080de7afc95aa1c19a6e6fc0e0708ced2eadc4 (patch)
treebdda434976bc09c864f2e4fa6f16ba1952b1e555 /unix/f2c/libf2c/pow_di.c
downloadiraf-linux-fa080de7afc95aa1c19a6e6fc0e0708ced2eadc4.tar.gz
Initial commit
Diffstat (limited to 'unix/f2c/libf2c/pow_di.c')
-rw-r--r--unix/f2c/libf2c/pow_di.c41
1 files changed, 41 insertions, 0 deletions
diff --git a/unix/f2c/libf2c/pow_di.c b/unix/f2c/libf2c/pow_di.c
new file mode 100644
index 00000000..abf36cb7
--- /dev/null
+++ b/unix/f2c/libf2c/pow_di.c
@@ -0,0 +1,41 @@
+#include "f2c.h"
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#ifdef KR_headers
+double pow_di(ap, bp) doublereal *ap; integer *bp;
+#else
+double pow_di(doublereal *ap, integer *bp)
+#endif
+{
+double pow, x;
+integer n;
+unsigned long u;
+
+pow = 1;
+x = *ap;
+n = *bp;
+
+if(n != 0)
+ {
+ if(n < 0)
+ {
+ n = -n;
+ x = 1/x;
+ }
+ for(u = n; ; )
+ {
+ if(u & 01)
+ pow *= x;
+ if(u >>= 1)
+ x *= x;
+ else
+ break;
+ }
+ }
+return(pow);
+}
+#ifdef __cplusplus
+}
+#endif