BSD 4_4 release

[unix-history] / usr / src / usr.bin / f77 / libF77 / pow_ci.c

diff --git a/usr/src/usr.bin/f77/libF77/pow_ci.c b/usr/src/usr.bin/f77/libF77/pow_ci.c
index 8ff29bc..dad213e 100644 (file)
--- a/usr/src/usr.bin/f77/libF77/pow_ci.c
+++ b/usr/src/usr.bin/f77/libF77/pow_ci.c
@@ -1,20 +1,71 @@
-/*
- *     "@(#)pow_ci.c   1.1"
+/*-
+ * Copyright (c) 1980 The Regents of the University of California.
+ * All rights reserved.
+ *
+ * This module is believed to contain source code proprietary to AT&T.
+ * Use and redistribution is subject to the Berkeley Software License
+ * Agreement and your Software Agreement with AT&T (Western Electric).

  */
 
  */
 

+#ifndef lint
+static char sccsid[] = "@(#)pow_ci.c   5.4 (Berkeley) 4/12/91";
+#endif /* not lint */
+

 #include "complex"
 
 #include "complex"
 

+#ifdef tahoe
+
+#define        C_MULEQ(A,B)    \
+       t = (A).real * (B).real - (A).imag * (B).imag,\
+       (A).imag = (A).real * (B).imag + (A).imag * (B).real,\
+       (A).real = t    /* A *= B */
+
+void

 pow_ci(p, a, b)        /* p = a**b  */
 pow_ci(p, a, b)        /* p = a**b  */

-complex *p, *a;
-long int *b;
+       complex *p, *a;
+       long *b;

 {
 {

-dcomplex p1, a1;
+       register long n = *b;
+       register float t;
+       complex x;

 
 

-a1.dreal = a->real;
-a1.dimag = a->imag;
+       x = *a;
+       p->real = (float)1, p->imag = (float)0;
+       if (!n)
+               return;
+       if (n < 0) {
+               c_div(&x, p, a);
+               n = -n;
+       }
+       while (!(n&1)) {
+               C_MULEQ(x, x);
+               n >>= 1;
+       }
+       for (*p = x; --n > 0; C_MULEQ(*p, x))
+               while (!(n&1)) {
+                       C_MULEQ(x, x);
+                       n >>= 1;
+               }
+}
+
+#else /* !tahoe */

 
 

-pow_zi(&p1, &a1, b);
+extern void pow_zi();

 
 

-p->real = p1.dreal;
-p->imag = p1.dimag;
+void
+pow_ci(p, a, b)        /* p = a**b  */
+       complex *p, *a;
+       long *b;
+{
+       dcomplex p1, a1;
+
+       a1.dreal = a->real;
+       a1.dimag = a->imag;
+
+       pow_zi(&p1, &a1, b);
+
+       p->real = p1.dreal;
+       p->imag = p1.dimag;

 }
 }

+
+#endif /* tahoe */