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Diffstat (limited to 'src/regress/lib/libc/cephes/drand.c')
| -rw-r--r-- | src/regress/lib/libc/cephes/drand.c | 174 |
1 files changed, 0 insertions, 174 deletions
diff --git a/src/regress/lib/libc/cephes/drand.c b/src/regress/lib/libc/cephes/drand.c deleted file mode 100644 index 7f7000b4e8..0000000000 --- a/src/regress/lib/libc/cephes/drand.c +++ /dev/null | |||
| @@ -1,174 +0,0 @@ | |||
| 1 | /* $OpenBSD: drand.c,v 1.1 2011/07/02 18:11:01 martynas Exp $ */ | ||
| 2 | |||
| 3 | /* | ||
| 4 | * Copyright (c) 2008 Stephen L. Moshier <steve@moshier.net> | ||
| 5 | * | ||
| 6 | * Permission to use, copy, modify, and distribute this software for any | ||
| 7 | * purpose with or without fee is hereby granted, provided that the above | ||
| 8 | * copyright notice and this permission notice appear in all copies. | ||
| 9 | * | ||
| 10 | * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES | ||
| 11 | * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF | ||
| 12 | * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR | ||
| 13 | * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES | ||
| 14 | * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN | ||
| 15 | * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF | ||
| 16 | * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. | ||
| 17 | */ | ||
| 18 | |||
| 19 | /* drand.c | ||
| 20 | * | ||
| 21 | * Pseudorandom number generator | ||
| 22 | * | ||
| 23 | * | ||
| 24 | * | ||
| 25 | * SYNOPSIS: | ||
| 26 | * | ||
| 27 | * double y, drand(); | ||
| 28 | * | ||
| 29 | * drand( &y ); | ||
| 30 | * | ||
| 31 | * | ||
| 32 | * | ||
| 33 | * DESCRIPTION: | ||
| 34 | * | ||
| 35 | * Yields a random number 1.0 <= y < 2.0. | ||
| 36 | * | ||
| 37 | * The three-generator congruential algorithm by Brian | ||
| 38 | * Wichmann and David Hill (BYTE magazine, March, 1987, | ||
| 39 | * pp 127-8) is used. The period, given by them, is | ||
| 40 | * 6953607871644. | ||
| 41 | * | ||
| 42 | * Versions invoked by the different arithmetic compile | ||
| 43 | * time options DEC, IBMPC, and MIEEE, produce | ||
| 44 | * approximately the same sequences, differing only in the | ||
| 45 | * least significant bits of the numbers. The UNK option | ||
| 46 | * implements the algorithm as recommended in the BYTE | ||
| 47 | * article. It may be used on all computers. However, | ||
| 48 | * the low order bits of a double precision number may | ||
| 49 | * not be adequately random, and may vary due to arithmetic | ||
| 50 | * implementation details on different computers. | ||
| 51 | * | ||
| 52 | * The other compile options generate an additional random | ||
| 53 | * integer that overwrites the low order bits of the double | ||
| 54 | * precision number. This reduces the period by a factor of | ||
| 55 | * two but tends to overcome the problems mentioned. | ||
| 56 | * | ||
| 57 | */ | ||
| 58 | |||
| 59 | #include "mconf.h" | ||
| 60 | |||
| 61 | |||
| 62 | /* Three-generator random number algorithm | ||
| 63 | * of Brian Wichmann and David Hill | ||
| 64 | * BYTE magazine, March, 1987 pp 127-8 | ||
| 65 | * | ||
| 66 | * The period, given by them, is (p-1)(q-1)(r-1)/4 = 6.95e12. | ||
| 67 | */ | ||
| 68 | |||
| 69 | static int sx = 1; | ||
| 70 | static int sy = 10000; | ||
| 71 | static int sz = 3000; | ||
| 72 | |||
| 73 | static union { | ||
| 74 | double d; | ||
| 75 | unsigned short s[4]; | ||
| 76 | } unkans; | ||
| 77 | |||
| 78 | /* This function implements the three | ||
| 79 | * congruential generators. | ||
| 80 | */ | ||
| 81 | |||
| 82 | static int ranwh() | ||
| 83 | { | ||
| 84 | int r, s; | ||
| 85 | |||
| 86 | /* sx = sx * 171 mod 30269 */ | ||
| 87 | r = sx/177; | ||
| 88 | s = sx - 177 * r; | ||
| 89 | sx = 171 * s - 2 * r; | ||
| 90 | if( sx < 0 ) | ||
| 91 | sx += 30269; | ||
| 92 | |||
| 93 | |||
| 94 | /* sy = sy * 172 mod 30307 */ | ||
| 95 | r = sy/176; | ||
| 96 | s = sy - 176 * r; | ||
| 97 | sy = 172 * s - 35 * r; | ||
| 98 | if( sy < 0 ) | ||
| 99 | sy += 30307; | ||
| 100 | |||
| 101 | /* sz = 170 * sz mod 30323 */ | ||
| 102 | r = sz/178; | ||
| 103 | s = sz - 178 * r; | ||
| 104 | sz = 170 * s - 63 * r; | ||
| 105 | if( sz < 0 ) | ||
| 106 | sz += 30323; | ||
| 107 | /* The results are in static sx, sy, sz. */ | ||
| 108 | return 0; | ||
| 109 | } | ||
| 110 | |||
| 111 | /* drand.c | ||
| 112 | * | ||
| 113 | * Random double precision floating point number between 1 and 2. | ||
| 114 | * | ||
| 115 | * C callable: | ||
| 116 | * drand( &x ); | ||
| 117 | */ | ||
| 118 | |||
| 119 | int drand( a ) | ||
| 120 | double *a; | ||
| 121 | { | ||
| 122 | unsigned short r; | ||
| 123 | #ifdef DEC | ||
| 124 | unsigned short s, t; | ||
| 125 | #endif | ||
| 126 | |||
| 127 | /* This algorithm of Wichmann and Hill computes a floating point | ||
| 128 | * result: | ||
| 129 | */ | ||
| 130 | ranwh(); | ||
| 131 | unkans.d = sx/30269.0 + sy/30307.0 + sz/30323.0; | ||
| 132 | r = unkans.d; | ||
| 133 | unkans.d -= r; | ||
| 134 | unkans.d += 1.0; | ||
| 135 | |||
| 136 | /* if UNK option, do nothing further. | ||
| 137 | * Otherwise, make a random 16 bit integer | ||
| 138 | * to overwrite the least significant word | ||
| 139 | * of unkans. | ||
| 140 | */ | ||
| 141 | #ifdef UNK | ||
| 142 | /* do nothing */ | ||
| 143 | #else | ||
| 144 | ranwh(); | ||
| 145 | r = sx * sy + sz; | ||
| 146 | #endif | ||
| 147 | |||
| 148 | #ifdef DEC | ||
| 149 | /* To make the numbers as similar as possible | ||
| 150 | * in all arithmetics, the random integer has | ||
| 151 | * to be inserted 3 bits higher up in a DEC number. | ||
| 152 | * An alternative would be put it 3 bits lower down | ||
| 153 | * in all the other number types. | ||
| 154 | */ | ||
| 155 | s = unkans.s[2]; | ||
| 156 | t = s & 07; /* save these bits to put in at the bottom */ | ||
| 157 | s &= 0177770; | ||
| 158 | s |= (r >> 13) & 07; | ||
| 159 | unkans.s[2] = s; | ||
| 160 | t |= r << 3; | ||
| 161 | unkans.s[3] = t; | ||
| 162 | #endif | ||
| 163 | |||
| 164 | #ifdef IBMPC | ||
| 165 | unkans.s[0] = r; | ||
| 166 | #endif | ||
| 167 | |||
| 168 | #ifdef MIEEE | ||
| 169 | unkans.s[3] = r; | ||
| 170 | #endif | ||
| 171 | |||
| 172 | *a = unkans.d; | ||
| 173 | return 0; | ||
| 174 | } | ||
