Return to pow_ri.c CVS log

Up to [CSRG BSD Unix] / 43BSDReno / lib / libF77

Annotation of 43BSDReno/lib/libF77/pow_ri.c, revision 1.1.1.1

1.1       root        1: /*
                      2:  * Copyright (c) 1980 Regents of the University of California.
                      3:  * All rights reserved.  The Berkeley software License Agreement
                      4:  * specifies the terms and conditions for redistribution.
                      5:  *
                      6:  *     @(#)pow_ri.c    5.4     1/24/88
                      7:  */
                      8: 
                      9: #ifdef tahoe
                     10: #define        double  float
                     11: #endif /* tahoe */
                     12: 
                     13: float
                     14: pow_ri(ap, bp)
                     15:        float *ap;
                     16:        long *bp;
                     17: {
                     18:        register long n = *bp;
                     19: #ifdef tahoe
                     20:        register
                     21: #endif /* tahoe */
                     22:        double y, x = *ap;
                     23: 
                     24:        if (!n)
                     25:                return((double)1);
                     26:        if (n < 0) {
                     27:                x = (double)1 / x;
                     28:                n = -n;
                     29:        }
                     30:        while (!(n&1)) {
                     31:                x *= x;
                     32:                n >>= 1;
                     33:        }
                     34:        for (y = x; --n > 0; y *= x)
                     35:                while (!(n&1)) {
                     36:                        x *= x;
                     37:                        n >>= 1;
                     38:                }
                     39:        return(y);
                     40: }
                     41: #ifdef tahoe
                     42: #undef double
                     43: #endif /* tahoe */

This archive runs on limited infrastructure. Preserving old code on modern bandwidth. Automated agents are requested to crawl responsibly.