1 # -*- coding: utf-8 -*-

     2 """

     3     sphinx.ext.mathbase

     4     ~~~~~~~~~~~~~~~~~~~

     5 

     6     Set up math support in source files and LaTeX/text output.

     7 

     8     :copyright: 2008 by Georg Brandl.

     9     :license: BSD.

    10 """

    11 

    12 from docutils import nodes, utils

    13 from docutils.parsers.rst import directives

    14 

    15 

    16 class math(nodes.Inline, nodes.TextElement):

    17     pass

    18 

    19 class displaymath(nodes.Part, nodes.Element):

    20     pass

    21 

    22 class eqref(nodes.Inline, nodes.TextElement):

    23     pass

    24 

    25 

    26 def wrap_displaymath(math, label):

    27     parts = math.split('\n\n')

    28     ret = []

    29     for i, part in enumerate(parts):

    30         if label is not None and i == 0:

    31             ret.append('\\begin{split}%s\\end{split}' % part +

    32                        (label and '\\label{'+label+'}' or ''))

    33         else:

    34             ret.append('\\begin{split}%s\\end{split}\\notag' % part)

    35     return '\\begin{gather}\n' + '\\\\'.join(ret) + '\n\\end{gather}'

    36 

    37 

    38 def math_role(role, rawtext, text, lineno, inliner, options={}, content=[]):

    39     latex = utils.unescape(text, restore_backslashes=True)

    40     return [math(latex=latex)], []

    41 

    42 def eq_role(role, rawtext, text, lineno, inliner, options={}, content=[]):

    43     text = utils.unescape(text)

    44     node = eqref('(?)', '(?)', target=text)

    45     node['docname'] = inliner.document.settings.env.docname

    46     return [node], []

    47 

    48 def math_directive(name, arguments, options, content, lineno,

    49                    content_offset, block_text, state, state_machine):

    50     latex = '\n'.join(content)

    51     if arguments and arguments[0]:

    52         latex = arguments[0] + '\n\n' + latex

    53     node = displaymath()

    54     node['latex'] = latex

    55     node['label'] = options.get('label', None)

    56     node['nowrap'] = 'nowrap' in options

    57     node['docname'] = state.document.settings.env.docname

    58     ret = [node]

    59     if node['label']:

    60         tnode = nodes.target('', '', ids=['equation-' + node['label']])

    61         state.document.note_explicit_target(tnode)

    62         ret.insert(0, tnode)

    63     return ret

    64 

    65 

    66 def latex_visit_math(self, node):

    67     self.body.append('$' + node['latex'] + '$')

    68     raise nodes.SkipNode

    69 

    70 def latex_visit_displaymath(self, node):

    71     if node['nowrap']:

    72         self.body.append(node['latex'])

    73     else:

    74         label = node['label'] and node['docname'] + '-' + node['label'] or None

    75         self.body.append(wrap_displaymath(node['latex'], label))

    76     raise nodes.SkipNode

    77 

    78 def latex_visit_eqref(self, node):

    79     self.body.append('\\eqref{%s-%s}' % (node['docname'], node['target']))

    80     raise nodes.SkipNode

    81 

    82 

    83 def text_visit_math(self, node):

    84     self.add_text(node['latex'])

    85     raise nodes.SkipNode

    86 

    87 def text_visit_displaymath(self, node):

    88     self.new_state()

    89     self.add_text(node['latex'])

    90     self.end_state()

    91     raise nodes.SkipNode

    92 

    93 def text_visit_eqref(self, node):

    94     self.add_text(node['target'])

    95     raise nodes.SkipNode

    96 

    97 

    98 def html_visit_eqref(self, node):

    99     self.body.append('<a href="#equation-%s">' % node['target'])

   100 

   101 def html_depart_eqref(self, node):

   102     self.body.append('</a>')

   103 

   104 

   105 def number_equations(app, doctree, docname):

   106     num = 0

   107     numbers = {}

   108     for node in doctree.traverse(displaymath):

   109         if node['label'] is not None:

   110             num += 1

   111             node['number'] = num

   112             numbers[node['label']] = num

   113         else:

   114             node['number'] = None

   115     for node in doctree.traverse(eqref):

   116         if node['target'] not in numbers:

   117             continue

   118         num = '(%d)' % numbers[node['target']]

   119         node[0] = nodes.Text(num, num)

   120 

   121 

   122 def setup(app, htmlinlinevisitors, htmldisplayvisitors):

   123     app.add_node(math,

   124                  latex=(latex_visit_math, None),

   125                  text=(text_visit_math, None),

   126                  html=htmlinlinevisitors)

   127     app.add_node(displaymath,

   128                  latex=(latex_visit_displaymath, None),

   129                  text=(text_visit_displaymath, None),

   130                  html=htmldisplayvisitors)

   131     app.add_node(eqref,

   132                  latex=(latex_visit_eqref, None),

   133                  text=(text_visit_eqref, None),

   134                  html=(html_visit_eqref, html_depart_eqref))

   135     app.add_role('math', math_role)

   136     app.add_role('eq', eq_role)

   137     app.add_directive('math', math_directive, 1, (0, 1, 1),

   138                       label=directives.unchanged, nowrap=directives.flag)

   139     app.connect('doctree-resolved', number_equations)