source: project/random-swb/trunk/random-swb-eggdoc.scm @ 7358

Last change on this file since 7358 was 7358, checked in by Ivan Raikov, 12 years ago

Updated author address.

File size: 5.4 KB
Line 
1
2(use eggdoc)
3
4(define doc
5  `((eggdoc:begin
6     (name "swb-random")
7     (description "A random number generator based on the subtract-with-borrow (SWB) method.")
8     (author (url "http://chicken.wiki.br/ivan raikov" "Ivan Raikov"))
9
10     (history 
11      (version "1.5" "Bug fix in the setup file")
12      (version "1.4" "Removed easyffi dependency")
13      (version "1.3" "Build script updated for better cross-platform compatibility")
14      (version "1.2" "Fixed the .meta file to include the documentation")
15      (version "1.1" "License upgrade to GPL v3")
16      (version "1.0" "Initial release"))
17
18     (requires)
19
20     (usage "(require-extension swb-random)")
21
22     (download "swb-random.egg")
23
24     (documentation
25     
26      (p "The swb-random library is a port of the SML/NJ implementation of "
27         "a random number generator using the subtract-with-borrow (SWB) method "
28         "described by Marsaglia and Zaman in " 
29         (pre "A New Class of Random Number Generators, "
30              "Ann. Applied Prob. 1(3), 1991, pp. 462-480. "))
31
32      (p "The SWB generator implemented in this library is a 30-bit generator with lags 48 and 8. "
33         "It has period " (tt "(2^1487 - 2^247)/105") " or about " (tt "10^445") 
34         ". The SWB generator acts locally like a lagged Fibonacci generator "
35         "and thus it is combined with a linear congruential generator "
36         (tt "(48271*a)mod(2^30-1)") ". ")
37
38      (subsection "Procedures"
39
40                  (procedure "make-swb-random-state:: CONG-SEED SHR-SEED -> SWB-STATE"
41                             (p "Creates an initial seed array and generator state. "
42                                "The seed vector is filled one bit at a time by taking "
43                                "the leading bit of the xor of a shift register and a "
44                                "congruential sequence.  The congruential generator is "
45                                (tt "(c*48271) mod (2^30 - 1)") ". The shift register "
46                                "generator is " (tt "c(I + L18)(I + R13)") ".  "
47                                "The same congruential generator continues to be used as a "
48                                "mixing generator with the SWB generator."))
49
50                  (procedure "swb-random!:: SWB-STATE -> FIXNUM"
51                             (p "Computes the next random number. The output from the SWB "
52                                "generator is xor-ed with a number from the linear "
53                                "congruential generator. This procedure modifies its input "
54                                "argument. "))
55
56                  (procedure "swb-random-natural!:: SWB-STATE -> FIXNUM"
57                             (p "Computes the next random number and returns its absolute value. "
58                                "The output from the SWB generator is xor-ed with a number from the "
59                                "linear congruential generator. This procedure modifies its input "
60                                "argument. "))
61
62                  (procedure "swb-random-real!:: SWB-STATE -> FLONUM"
63                             (p "Computes the two next random numbers and uses them to construct "
64                                "a real number of the range " (tt "[0..1]") ". "
65                                "The output from the SWB generator is xor-ed with a number from the "
66                                "linear congruential generator. This procedure modifies its input "
67                                "argument. "))
68
69                  (procedure "swb-random-range!:: (FIXNUM * FIXNUM) -> (SWB-STATE -> FIXNUM)"
70                             (p "Given a range " (tt "[i..j], 0 <= i < j") ",  returns a "
71                                "procedure that takes in a random number generator state and "
72                                "computes a random number in the given range. "
73                                "The output from the SWB generator is xor-ed with a number from the "
74                                "linear congruential generator. The returned procedure modifies its input "
75                                "argument. "))
76
77                  (procedure "swb-random:: SWB-STATE -> SWB-STATE * FIXNUM"
78                             (p "Computes the next random number. The output from the SWB "
79                                "generator is xor-ed with a number from the linear "
80                                "congruential generator. The new generator state is returned along "
81                                "with the random number. "))
82
83                  (procedure "swb-random-natural:: SWB-STATE -> SWB-STATE * FIXNUM"
84                             (p "Computes the next random number and returns its absolute values. "
85                                "The output from the SWB generator is xor-ed with a number from the linear "
86                                "congruential generator. The new generator state is returned along "
87                                "with the random number. "))
88
89                  (procedure "swb-random-real:: SWB-STATE -> SWB-STATE * FLONUM"
90                             (p "Computes the two next random numbers and uses them to construct "
91                                "a real number of the range " (tt "[0..1]") ". "
92                                "The output from the SWB generator is xor-ed with a number from the "
93                                "linear congruential generator. The new generator state is returned along "
94                                "with the random number. "))
95
96                  (procedure "swb-random-range:: (FIXNUM * FIXNUM) -> (SWB-STATE -> SWB-STATE * FIXNUM)"
97                             (p "Given a range " (tt "[i..j], 0 <= i < j") ",  returns a "
98                                "procedure that takes in a random number generator state and "
99                                "computes a random number in the given range. "
100                                "The output from the SWB generator is xor-ed with a number from the "
101                                "linear congruential generator. The new generator state is returned along "
102                                "with the random number. "))))
103                 
104
105     (examples)
106
107     (license
108      "Copyright 2007 Ivan Raikov.
109
110This program is free software: you can redistribute it and/or modify
111it under the terms of the GNU General Public License as published by
112the Free Software Foundation, either version 3 of the License, or (at
113your option) any later version.
114
115This program is distributed in the hope that it will be useful, but
116WITHOUT ANY WARRANTY; without even the implied warranty of
117MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
118General Public License for more details.
119
120A full copy of the GPL license can be found at
121<http://www.gnu.org/licenses/>."))))
122
123(if (eggdoc->html doc) (void))
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