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
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
|
%D \module
%D [ file=lang-frq,
%D version=2004.01.15,
%D title=\CONTEXT\ Language Macros,
%D subtitle=Frequency Tables,
%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.
\endinput
\writestatus{loading}{ConTeXt Language Macros / Frequency Tables}
%D Some day I might redo this \LUA. But anyway, who uses it. It's rather
%D old code.
\unprotect
%M \usemodule[layout]
%D \macros
%D {charwidthmethod}
%D
%D This module implements a method for determining the width of an
%D average character in a language. It uses the dimensions of the
%D current fonts.
%D
%D \def\ShwChrWd#1#2#3%
%D {\chardef\charwidthmethod#1\relax
%D \mainlanguage[#2#3]\the\dimexpr(\averagecharwidth)}
%D
%D \starttabulate[|c|c|c|c|c|c|]
%D \HL
%D \NC \NC\bf0=amount\NC\bf1=.5em\NC2=ex\NC\bf3=frequency\NC\bf4=list\NC\NR
%D \HL
%D \NC\bf en\NC\ShwChrWd0en\NC\ShwChrWd1en\NC\ShwChrWd2en\NC\ShwChrWd3en\NC\ShwChrWd4en\NC\NR
%D \NC\bf nl\NC\ShwChrWd0nl\NC\ShwChrWd1nl\NC\ShwChrWd2nl\NC\ShwChrWd3nl\NC\ShwChrWd4nl\NC\NR
%D \NC\bf de\NC\ShwChrWd0de\NC\ShwChrWd1de\NC\ShwChrWd2de\NC\ShwChrWd3de\NC\ShwChrWd4de\NC\NR
%D \HL
%D \stoptabulate
%D
%D Method~1 ignores the widths and assumes that each character has a
%D width of .5em, which is true for most monospaced fonts. Method~2
%D takes the x as starting point, and assumes that it's height kind of
%D matches its width. Method~3 is the best one, and determines the
%D average width based on the language specific character table.
%D Method~4 is a mixture between the first two methods: character
%D specific widths applied to an equal distribution. Method~0 reports
%D the total count, which normally is~100.
\chardef\charwidthmethod=3 % 0=amount 1=em 2=ex 3=frequency 4=flattened >4=ex
%D \macros
%D {charwidthlanguage}
%D
%D The language used for the calculations is defined as:
\def\charwidthlanguage{\currentmainlanguage}
%D \macros
%D {charfreq}
%D
%D This method comes into action in the following macro:
\def\charfreq#1 #2 % character fraction
{+(\ifcase\charwidthmethod
#2\dimexpr100\onepoint\relax
\or
#2\dimexpr\emwidth/2\relax
\or
#2\dimexpr\exheight\relax
\or
#2\fontcharwd\font`#1%
\or
\dimexpr100\fontcharwd\font`#1/\charactertsize\charwidthlanguage\relax % ugly hack
\else
#2\dimexpr\exheight\relax
\fi)}
%D \macros
%D {startcharactertable}
%D
%D A frequency table is defined with the following macro. The \type
%D {charfreq} macro is used in this table.
\installcorenamespace{frequencywidths}
\installcorenamespace{frequencycounts}
\let\stopcharactertable\relax
\unexpanded\def\startcharactertable[#1]#2\stopcharactertable % \dimexpr has fuzzy lookahead
{\startnointerference
\setgvalue{\??frequencywidths#1}{#2}% the width vector
\scratchcounter\zerocount \def\charfreq##1 ##2 {\advance\scratchcounter\plusone} #2%
\setxvalue{\??frequencycounts#1}{\the\scratchcounter}% the character count
\stopnointerference}
%D \macros
%D {charactertable,charactertsize}
%D
%D The table content as well as the number of entries can be fetched with
%D the following two macros. The architecture of the table and calling
%D macro permits a fully expandable application.
\def\charactertable#1%
{\csname\??frequencywidths\ifcsname\??frequencywidths#1\endcsname#1\else\s!en\fi\endcsname}
\def\charactertsize#1%
{\csname\??frequencycounts\ifcsname\??frequencycounts#1\endcsname#1\else\s!en\fi\endcsname}
%D Although it is of hardly any use, you can inherit a character table:
%D
%D \starttyping
%D \startcharactertable[cz] \charactertable{en} \stopcharactertable
%D \stoptyping
\startcharactertable[en]
% empty
\stopcharactertable % kind of default
%D \macros
%D {averagecharwidth}
%D
%D This macro reports the average width for the current main
%D language (\the \dimexpr (\averagecharwidth)).
\def\averagecharwidth{\dimexpr(\zeropoint\charactertable\charwidthlanguage)/100\relax}
\unexpanded\def\showcharfreq
{\hbox\bgroup
\charwidthlanguage:%
\dostepwiserecurse\zerocount\plusfour\plusone
{\chardef\charwidthmethod\recurselevel\relax
\enspace\recurselevel/\the\dimexpr(\averagecharwidth)}%
\egroup}
%D Just for fun, we show a few frequency tables as graphic (\in {figure}
%D [fig:charfreq]).
%D
%D \startbuffer
%D \definepalet [charfreq] [en=darkred, nl=darkgreen, de=darkblue]
%D
%D \def\charfreq#1 #2 %
%D {\startMPdrawing
%D interim linejoin := butt ;
%D a := ASCII "#1" ;
%D if (a >= (ASCII "a")) and (a <= (ASCII "z")) :
%D draw ((0,#2*.25cm)--origin--(0,#2*.5cm))
%D shifted (a*4mm+o,0)
%D withpen pencircle scaled .5mm
%D withcolor c;
%D fi ;
%D \stopMPdrawing}
%D
%D \resetMPdrawing
%D \startMPdrawing
%D numeric a, o ; a := o := 0 ;
%D color c ; c := .5white ;
%D string s ; s := "" ;
%D \stopMPdrawing
%D
%D \startMPdrawing o := 0mm ; c := \MPcolor{charfreq:en} ; \stopMPdrawing
%D \charactertable{en}
%D
%D \startMPdrawing o := 1mm ; c := \MPcolor{charfreq:nl} ; \stopMPdrawing
%D \charactertable{nl}
%D
%D \startMPdrawing o := 2mm ; c := \MPcolor{charfreq:de} ; \stopMPdrawing
%D \charactertable{de}
%D
%D \startMPdrawing
%D for a := ASCII "a" upto ASCII "z" :
%D draw textext.bot("\strut\tttf " & char a) shifted (a*4mm+1mm,-1mm) ;
%D endfor ;
%D \stopMPdrawing
%D
%D \MPdrawingdonetrue \getMPdrawing \resetMPdrawing
%D \stopbuffer
%D
%D \placefigure
%D [here]
%D [fig:charfreq]
%D {The character distributions for English, Dutch and German.}
%D {\getbuffer}
%D
%D A few samples of usage of this mechanism are shown below:
%D
%D \startbuffer
%D {\mainlanguage[en]\hsize65\averagecharwidth\mainlanguage[en]\input ward \blank}
%D {\mainlanguage[nl]\hsize65\averagecharwidth\mainlanguage[en]\input ward \blank}
%D {\mainlanguage[de]\hsize65\averagecharwidth\mainlanguage[en]\input ward \blank}
%D \stopbuffer
%D
%D \typebuffer \getbuffer
%D
%D Although the widthts differ, the consequenes for breaking the paragraph
%D into lines are minimal.
%D \macros
%D {freezeaveragecharacterwidth}
%D
%D This macro can be used to make sure that the width does not change during a
%D page break when another font is used.
\let\normalaveragecharacterwidth\averagecharacterwidth
\unexpanded\def\freezeaveragecharacterwidth % global
{\xdef\averagecharacterwidth{\dimexpr\the\normalaveragecharacterwidth\relax}}
%D Example:
%D
%D \starttyping
%D \input lang-frq.mkiv
%D \input lang-frd.mkiv
%D
%D \setupbodyfont
%D [dejavu]
%D
%D \setemeasure{textwidth}{\the\dimexpr70\averagecharwidth}
%D
%D \setuplayout
%D [width=\measure{textwidth}]
%D
%D \showframe
%D
%D \starttext
%D \input ward
%D \stoptext
%D \stoptyping
\protect \endinput
|
