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
|
// Copyright (C) 2000-2007, Luca Padovani <padovani@sti.uniurb.it>.
//
// This file is part of GtkMathView, a flexible, high-quality rendering
// engine for MathML documents.
//
// GtkMathView is free software; you can redistribute it and/or modify it
// under the terms of the GNU Lesser General Public License as published
// by the Free Software Foundation; either version 3 of the License, or
// (at your option) any later version.
//
// GtkMathView is distributed in the hope that it will be useful, but
// WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
// Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with this program. If not, see <http://www.gnu.org/licenses/>.
/* Generate a continued fraction that represents the square root of
* the first argument (default = 2.0) to the second argument (default
* = 2) levels. The third argument optional argument is a file to
* save the resulting xml to. */
#include <gtk/gtk.h>
#include "gtkmathview_libxml2.h"
#include <stdio.h>
#include <libxml/parser.h>
#include <libxml/tree.h>
#include <math.h>
int main(int argc, char *argv[]) {
gtk_init (&argc, &argv);
GtkWidget *window = gtk_window_new (GTK_WINDOW_TOPLEVEL);
gtk_widget_show (window);
g_signal_connect(GTK_OBJECT(window),
"delete_event",
(GtkSignalFunc) gtk_main_quit, NULL);
GtkWidget* math_view = gtk_math_view_new(NULL, NULL);
/*
* Creates a new document, a node and set it as a root node
*/
xmlDocPtr doc = xmlNewDoc(BAD_CAST "1.0");
xmlNodePtr root_node = xmlNewNode(NULL, BAD_CAST "math");
xmlDocSetRootElement(doc, root_node);
// gtk_math_view_load_document is very picky about the namespace
// used, so we have to make sure we set the ns for the document.
xmlNsPtr ns = xmlNewNs(root_node, BAD_CAST "http://www.w3.org/1998/Math/MathML", BAD_CAST "m");
xmlNewProp(root_node, BAD_CAST "display" , BAD_CAST "block");
xmlSetNs(root_node, ns);
/*
* xmlNewChild() creates a new node, which is "attached" as child node
* of root_node node.
*/
/* Here is the sort of mathml we want to generate.
<mi>1</mi>
<mo>+</mo>
<mfrac>
<mi>1</mi>
<mrow>
<mi>1</mi>
<mo>+</mo>
<mfrac>
<mi>1</mi>
<mrow>
<mi>1</mi>
<mo>+</mo>
<mi>...</mi>
</mrow>
</mfrac>
</mrow>
</mfrac>
*/
double rootand = 2;
if(argc > 1) {
sscanf(argv[1], "%lf", &rootand);
}
// We could just let a = 1 and b = rootand - 1, but this is more fun.
double a = trunc(sqrt(rootand));
double b = rootand - a*a;
printf("rooting %g (%g^2 + %g)\n", rootand, a, b);
char rootand_str[256], a_str[256], b_str[256];
sprintf(rootand_str, "%g", rootand);
sprintf(a_str, "%g", a);
sprintf(b_str, "%g", b);
xmlNodePtr sqrt_node = xmlNewChild(root_node, NULL, BAD_CAST "msqrt", NULL);
xmlNewChild(sqrt_node, ns, BAD_CAST "mi", BAD_CAST rootand_str);
xmlNewChild(root_node, ns, BAD_CAST "mo", BAD_CAST "=");
xmlNewChild(root_node, ns, BAD_CAST "mi", BAD_CAST a_str);
xmlNewChild(root_node, ns, BAD_CAST "mo", BAD_CAST "+");
// Now we must create the continued fraction
sprintf(rootand_str, "%g", rootand-1);
xmlNodePtr node = root_node;
int layers = 2;
if(argc > 2) {
sscanf(argv[2], "%d", &layers);
}
for (; --layers >= 0;) {
node = xmlNewChild(node, NULL, BAD_CAST "mfrac", NULL);
xmlNewChild(node, ns, BAD_CAST "mi", BAD_CAST b_str);
xmlNodePtr denom = xmlNewChild(node, NULL, BAD_CAST "mrow", NULL);
xmlNewChild(denom, ns, BAD_CAST "mi", BAD_CAST a_str);
xmlNewChild(denom, ns, BAD_CAST "mo", BAD_CAST "+");
node = denom;
}
xmlNewChild(node, ns, BAD_CAST "mi", BAD_CAST "...");
// If we have a second argument, save the mathml to disk.
if(argc > 3)
xmlSaveFormatFileEnc(argv[3], doc, "UTF-8", 1);
gtk_math_view_load_document(GTK_MATH_VIEW(math_view), doc);
gtk_container_add (GTK_CONTAINER (window), math_view);
gtk_widget_show (math_view);
gtk_main ();
/*free the document */
xmlFreeDoc(doc);
/*
*Free the global variables that may
*have been allocated by the parser.
*/
xmlCleanupParser();
return 0;
}
|
