1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
|
%D \module
%D [ file=supp-ran,
%D version=1998.01.21,
%D title=\CONTEXT\ Support Macros,
%D subtitle=Random Number Generation,
%D author=Hans Hagen,
%D date=\currentdate,
%D copyright={PRAGMA ADE \& \CONTEXT\ Development Team}]
%C
%C This module is part of the \CONTEXT\ macro||package and is
%C therefore copyrighted by \PRAGMA. See mreadme.pdf for
%C details.
\writestatus{loading}{ConTeXt Support Macros / Random Number Generation}
%D \macros
%D {getrandomcount, getrandomdimen,
%D getrandomfloat, getrandomnumber,
%D setrandomseed, getrandomseed}
%D
%D This module load Donald Arseneau's generic file
%D \type{random.tex}. A small shell is needed because we
%D redefine some \TEX\ primitives. We also use different names
%D for the two generators and add an extra one.
%D
%D \starttyping
%D \getrandomcount \countregister {minimum} {maximum}
%D \getrandomdimen \dimenregister {minimum} {maximum}
%D \getrandomnumber \macroname {minimum} {maximum}
%D \getrandomfloat \macroname {minimum} {maximum}
%D \stoptyping
%D
%D Of course the file \type{random.tex} needs to be present.
%D To prevent name clashes, the \CONTEXT\ distribution
%D contains a copy in \type {thrd-ran.tex}.
%D
%D The randomseed can be set by:
%D
%D \starttyping
%d \setrandomseed{number>0}
%D \stoptyping
%D
%D and get by:
%D
%D \starttyping
%D \getrandomseed\randomseed
%D \stoptyping
\input thrd-ran.mkii
\ifx\uniformdeviate\undefined
\let\verynormalnextrandom\nextrandom
\def\normalnextrandom
{\bgroup
\let\time \normaltime
\let\day \normalday
\let\month\normalmonth
\let\year \normalyear
\verynormalnextrandom
\egroup}
\else
\writestatus{loading}{using TeX's built in randomizer (overloading macro)}
% For the meaning of the magic number, see \type {thrd-ran.tex}.
%
% Taco suggested to use the following alternative because \type
% {\uniformdeviate} can return a zero (as expected) while
% Donalds Arseneau's alternative has a minimum of~1.
\def\nextrandom
{\normalsetrandomseed\randomi\relax
\global\randomi\numexpr\normaluniformdeviate2147483646+1\relax}
\let\normalnextrandom\nextrandom
\fi
\def\nextrandom
{\bgroup
\normalnextrandom
\gdef\nextrandom{\ifcase\randomseedfrozen\normalnextrandom\fi}%
\egroup}
\chardef\randomseedfrozen\zerocount
\def\freezerandomseed
{\ifcase\randomseedfrozen
\nextrandom \global\chardef\randomseedfrozen\plusone
\fi}
\def\defrostrandomseed
{\ifcase\randomseedfrozen\else
\global\chardef\randomseedfrozen\zerocount \nextrandom
\fi}
\let\getrandomcount\setrannum
\let\getrandomdimen\setrandim
\def\getrandomnumber#1#2#3%
{\getrandomcount\scratchcounter{#2}{#3}%
\edef#1{\the\scratchcounter}}
\def\getrandomfloat#1#2#3%
{\getrandomdimen\scratchdimen{#2\points}{#3\points}%
\edef#1{\withoutpt\the\scratchdimen}}
\unexpanded \def\setrandomseed#1%
{\global\randomi#1\relax} % global added
\unexpanded \def\getrandomseed#1%
{\edef#1{\number\randomi}}
\def\getnewrandomseed#1%
{\setrandomseed\minusone % signals thrd-ran to auto reseed
\nextrandom % this signal is needed for the
#1\randomi} % pseudo randomizer (see: third-ran)
\endinput
|
