1253 lines
46 KiB
Python
1253 lines
46 KiB
Python
# :Id: $Id: latex2mathml.py 9536 2024-02-01 13:04:22Z milde $
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# :Copyright: © 2005 Jens Jørgen Mortensen [1]_
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# © 2010, 2021, 2024 Günter Milde.
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#
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# :License: Released under the terms of the `2-Clause BSD license`_, in short:
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#
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# Copying and distribution of this file, with or without modification,
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# are permitted in any medium without royalty provided the copyright
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# notice and this notice are preserved.
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# This file is offered as-is, without any warranty.
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#
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# .. _2-Clause BSD license: https://opensource.org/licenses/BSD-2-Clause
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#
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# .. [1] the original `rst2mathml.py` in `sandbox/jensj/latex_math`
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"""Convert LaTex maths code into presentational MathML.
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This module is provisional:
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the API is not settled and may change with any minor Docutils version.
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"""
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# Usage:
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#
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# >>> from latex2mathml import *
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import re
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import unicodedata
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from docutils.utils.math import (MathError, mathalphabet2unichar,
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tex2unichar, toplevel_code)
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from docutils.utils.math.mathml_elements import (
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math, mtable, mrow, mtr, mtd, menclose, mphantom, msqrt, mi, mn, mo,
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mtext, msub, msup, msubsup, munder, mover, munderover, mroot, mfrac,
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mspace, MathRow)
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# Character data
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# --------------
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# LaTeX math macro to Unicode mappings.
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# Character categories.
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# identifiers -> <mi>
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letters = {'hbar': 'ℏ'} # Compatibility mapping: \hbar resembles italic ħ
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# "unicode-math" unifies \hbar and \hslash to ℏ.
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letters.update(tex2unichar.mathalpha)
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ordinary = tex2unichar.mathord # Miscellaneous symbols
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# special case: Capital Greek letters: (upright in TeX style)
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greek_capitals = {
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'Phi': '\u03a6', 'Xi': '\u039e', 'Sigma': '\u03a3',
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'Psi': '\u03a8', 'Delta': '\u0394', 'Theta': '\u0398',
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'Upsilon': '\u03d2', 'Pi': '\u03a0', 'Omega': '\u03a9',
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'Gamma': '\u0393', 'Lambda': '\u039b'}
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# functions -> <mi>
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functions = {
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# functions with a space in the name
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'liminf': 'lim\u202finf',
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'limsup': 'lim\u202fsup',
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'injlim': 'inj\u202flim',
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'projlim': 'proj\u202flim',
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# embellished function names (see handle_cmd() below)
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'varlimsup': 'lim',
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'varliminf': 'lim',
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'varprojlim': 'lim',
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'varinjlim': 'lim',
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# custom function name
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'operatorname': None,
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}
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functions.update((name, name) for name in
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('arccos', 'arcsin', 'arctan', 'arg', 'cos',
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'cosh', 'cot', 'coth', 'csc', 'deg',
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'det', 'dim', 'exp', 'gcd', 'hom',
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'ker', 'lg', 'ln', 'log', 'Pr',
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'sec', 'sin', 'sinh', 'tan', 'tanh'))
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# Function with limits: 'lim', 'sup', 'inf', 'max', 'min':
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# use <mo> to allow "movablelimits" attribute (see below).
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# modulo operator/arithmetic
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modulo_functions = {
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# cmdname: (binary, named, parentheses, padding)
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'bmod': (True, True, False, '0.278em'), # a mod n
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'pmod': (False, True, True, '0.444em'), # a (mod n)
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'mod': (False, True, False, '0.667em'), # a mod n
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'pod': (False, False, True, '0.444em'), # a (n)
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}
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# "mathematical alphabets": map identifiers to the corresponding
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# characters from the "Mathematical Alphanumeric Symbols" block
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math_alphabets = {
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# 'cmdname': 'mathvariant value' # package
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'mathbb': 'double-struck', # amssymb
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'mathbf': 'bold',
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'mathbfit': 'bold-italic', # isomath
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'mathcal': 'script',
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'mathfrak': 'fraktur', # amssymb
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'mathit': 'italic',
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'mathrm': 'normal',
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'mathscr': 'script', # mathrsfs et al
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'mathsf': 'sans-serif',
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'mathbfsfit': 'sans-serif-bold-italic', # unicode-math
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'mathsfbfit': 'sans-serif-bold-italic', # isomath
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'mathsfit': 'sans-serif-italic', # isomath
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'mathtt': 'monospace',
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# unsupported: bold-fraktur
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# bold-script
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# bold-sans-serif
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}
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# operator, fence, or separator -> <mo>
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stretchables = {
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# extensible delimiters allowed in left/right cmds
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'backslash': '\\',
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'uparrow': '\u2191', # ↑ UPWARDS ARROW
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'downarrow': '\u2193', # ↓ DOWNWARDS ARROW
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'updownarrow': '\u2195', # ↕ UP DOWN ARROW
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'Uparrow': '\u21d1', # ⇑ UPWARDS DOUBLE ARROW
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'Downarrow': '\u21d3', # ⇓ DOWNWARDS DOUBLE ARROW
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'Updownarrow': '\u21d5', # ⇕ UP DOWN DOUBLE ARROW
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'lmoustache': '\u23b0', # ⎰ … CURLY BRACKET SECTION
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'rmoustache': '\u23b1', # ⎱ … LEFT CURLY BRACKET SECTION
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'arrowvert': '\u23d0', # ⏐ VERTICAL LINE EXTENSION
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'bracevert': '\u23aa', # ⎪ CURLY BRACKET EXTENSION
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'lvert': '|', # left |
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'lVert': '\u2016', # left ‖
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'rvert': '|', # right |
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'rVert': '\u2016', # right ‖
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'Arrowvert': '\u2016', # ‖
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}
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stretchables.update(tex2unichar.mathfence)
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stretchables.update(tex2unichar.mathopen) # Braces
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stretchables.update(tex2unichar.mathclose) # Braces
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# >>> print(' '.join(sorted(set(stretchables.values()))))
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# [ \ ] { | } ‖ ↑ ↓ ↕ ⇑ ⇓ ⇕ ⌈ ⌉ ⌊ ⌋ ⌜ ⌝ ⌞ ⌟ ⎪ ⎰ ⎱ ⏐ ⟅ ⟆ ⟦ ⟧ ⟨ ⟩ ⟮ ⟯ ⦇ ⦈
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operators = {
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# negated symbols without pre-composed Unicode character
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'nleqq': '\u2266\u0338', # ≦̸
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'ngeqq': '\u2267\u0338', # ≧̸
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'nleqslant': '\u2a7d\u0338', # ⩽̸
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'ngeqslant': '\u2a7e\u0338', # ⩾̸
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'ngtrless': '\u2277\u0338', # txfonts
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'nlessgtr': '\u2276\u0338', # txfonts
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'nsubseteqq': '\u2AC5\u0338', # ⫅̸
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'nsupseteqq': '\u2AC6\u0338', # ⫆̸
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# compatibility definitions:
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'centerdot': '\u2B1D', # BLACK VERY SMALL SQUARE | mathbin
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'varnothing': '\u2300', # ⌀ DIAMETER SIGN | empty set
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'varpropto': '\u221d', # ∝ PROPORTIONAL TO | sans serif
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'triangle': '\u25B3', # WHITE UP-POINTING TRIANGLE | mathord
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'triangledown': '\u25BD', # WHITE DOWN-POINTING TRIANGLE | mathord
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# alias commands:
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'dotsb': '\u22ef', # ⋯ with binary operators/relations
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'dotsc': '\u2026', # … with commas
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'dotsi': '\u22ef', # ⋯ with integrals
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'dotsm': '\u22ef', # ⋯ multiplication dots
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'dotso': '\u2026', # … other dots
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# functions with movable limits (requires <mo>)
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'lim': 'lim',
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'sup': 'sup',
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'inf': 'inf',
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'max': 'max',
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'min': 'min',
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}
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operators.update(tex2unichar.mathbin) # Binary symbols
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operators.update(tex2unichar.mathrel) # Relation symbols, arrow symbols
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operators.update(tex2unichar.mathpunct) # Punctuation
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operators.update(tex2unichar.mathop) # Variable-sized symbols
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operators.update(stretchables)
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# special cases
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thick_operators = {
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# style='font-weight: bold;'
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'thicksim': '\u223C', # ∼
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'thickapprox': '\u2248', # ≈
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}
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small_operators = {
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# mathsize='75%'
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'shortmid': '\u2223', # ∣
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'shortparallel': '\u2225', # ∥
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'nshortmid': '\u2224', # ∤
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'nshortparallel': '\u2226', # ∦
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'smallfrown': '\u2322', # ⌢ FROWN
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'smallsmile': '\u2323', # ⌣ SMILE
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'smallint': '\u222b', # ∫ INTEGRAL
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}
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# Operators and functions with limits above/below in display formulas
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# and in index position inline (movablelimits=True)
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movablelimits = ('bigcap', 'bigcup', 'bigodot', 'bigoplus', 'bigotimes',
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'bigsqcup', 'biguplus', 'bigvee', 'bigwedge',
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'coprod', 'intop', 'ointop', 'prod', 'sum',
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'lim', 'max', 'min', 'sup', 'inf')
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# Depending on settings, integrals may also be in this category.
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# (e.g. if "amsmath" is loaded with option "intlimits", see
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# http://mirror.ctan.org/macros/latex/required/amsmath/amsldoc.pdf)
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# movablelimits.extend(('fint', 'iiiint', 'iiint', 'iint', 'int', 'oiint',
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# 'oint', 'ointctrclockwise', 'sqint',
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# 'varointclockwise',))
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# horizontal space -> <mspace>
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spaces = {'qquad': '2em', # two \quad
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'quad': '1em', # 18 mu
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'thickspace': '0.2778em', # 5mu = 5/18em
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';': '0.2778em', # 5mu thickspace
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' ': '0.25em', # inter word space
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'\n': '0.25em', # inter word space
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'medspace': '0.2222em', # 4mu = 2/9em
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':': '0.2222em', # 4mu medspace
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'thinspace': '0.1667em', # 3mu = 1/6em
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',': '0.1667em', # 3mu thinspace
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'negthinspace': '-0.1667em', # -3mu = -1/6em
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'!': '-0.1667em', # negthinspace
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'negmedspace': '-0.2222em', # -4mu = -2/9em
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'negthickspace': '-0.2778em', # -5mu = -5/18em
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}
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# accents: -> <mo stretchy="false"> in <mover>
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accents = {
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# TeX: spacing combining
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'acute': '´', # '\u0301'
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'bar': 'ˉ', # '\u0304'
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'breve': '˘', # '\u0306'
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'check': 'ˇ', # '\u030C'
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'dot': '˙', # '\u0307'
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'ddot': '¨', # '\u0308'
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'dddot': '˙˙˙', # '\u20DB' # or … ?
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'ddddot': '˙˙˙˙', # '\u20DC' # or ¨¨ ?
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'grave': '`', # '\u0300'
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'hat': 'ˆ', # '\u0302'
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'mathring': '˚', # '\u030A'
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'tilde': '~', # '\u0303' # tilde ~ or small tilde ˜?
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'vec': '→', # '\u20d7' # → too heavy, use scriptlevel="+1"
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}
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# limits etc. -> <mo> in <mover> or <munder>
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over = {
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# TeX: (char, offset-correction/em)
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'overbrace': ('\u23DE', -0.2), # DejaVu Math -0.6
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'overleftarrow': ('\u2190', -0.2),
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'overleftrightarrow': ('\u2194', -0.2),
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'overline': ('_', -0.2), # \u2012 does not stretch
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'overrightarrow': ('\u2192', -0.2),
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'widehat': ('^', -0.5),
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'widetilde': ('~', -0.3),
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}
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under = {'underbrace': ('\u23DF', 0.1), # DejaVu Math -0.7
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'underleftarrow': ('\u2190', -0.2),
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'underleftrightarrow': ('\u2194', -0.2),
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'underline': ('_', -0.8),
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'underrightarrow': ('\u2192', -0.2),
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}
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# Character translations
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# ----------------------
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# characters with preferred alternative in mathematical use
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# cf. https://www.w3.org/TR/MathML3/chapter7.html#chars.anomalous
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anomalous_chars = {'-': '\u2212', # HYPHEN-MINUS -> MINUS SIGN
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':': '\u2236', # COLON -> RATIO
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'~': '\u00a0', # NO-BREAK SPACE
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}
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# blackboard bold (Greek characters not working with "mathvariant" (Firefox 78)
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mathbb = {'Γ': '\u213E', # ℾ
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'Π': '\u213F', # ℿ
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'Σ': '\u2140', # ⅀
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'γ': '\u213D', # ℽ
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'π': '\u213C', # ℼ
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}
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# Matrix environments
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matrices = {
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# name: fences
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'matrix': ('', ''),
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'smallmatrix': ('', ''), # smaller, see begin_environment()!
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'pmatrix': ('(', ')'),
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'bmatrix': ('[', ']'),
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'Bmatrix': ('{', '}'),
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'vmatrix': ('|', '|'),
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'Vmatrix': ('\u2016', '\u2016'), # ‖
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'aligned': ('', ''),
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'cases': ('{', ''),
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}
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layout_styles = {
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'displaystyle': {'displaystyle': True, 'scriptlevel': 0},
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'textstyle': {'displaystyle': False, 'scriptlevel': 0},
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'scriptstyle': {'displaystyle': False, 'scriptlevel': 1},
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'scriptscriptstyle': {'displaystyle': False, 'scriptlevel': 2},
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}
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# See also https://www.w3.org/TR/MathML3/chapter3.html#presm.scriptlevel
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fractions = {
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# name: attributes
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'frac': {},
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'cfrac': {'displaystyle': True, 'scriptlevel': 0,
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'class': 'cfrac'}, # in LaTeX with padding
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'dfrac': layout_styles['displaystyle'],
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'tfrac': layout_styles['textstyle'],
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'binom': {'linethickness': 0},
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'dbinom': layout_styles['displaystyle'] | {'linethickness': 0},
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'tbinom': layout_styles['textstyle'] | {'linethickness': 0},
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}
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delimiter_sizes = ['', '1.2em', '1.623em', '2.047em', '2.470em']
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bigdelimiters = {'left': 0,
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'right': 0,
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'bigl': 1,
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'bigr': 1,
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'Bigl': 2,
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'Bigr': 2,
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'biggl': 3,
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'biggr': 3,
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'Biggl': 4,
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'Biggr': 4,
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}
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# LaTeX to MathML translation
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# ---------------------------
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# auxiliary functions
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# ~~~~~~~~~~~~~~~~~~~
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def tex_cmdname(string):
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"""Return leading TeX command name and remainder of `string`.
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>>> tex_cmdname('mymacro2') # up to first non-letter
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('mymacro', '2')
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>>> tex_cmdname('name 2') # strip trailing whitespace
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('name', '2')
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>>> tex_cmdname('_2') # single non-letter character
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('_', '2')
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"""
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m = re.match(r'([a-zA-Z]+)[ \n]*(.*)', string, re.DOTALL)
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if m is None:
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m = re.match(r'(.?)(.*)', string, re.DOTALL)
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return m.group(1), m.group(2)
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# Test:
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#
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# >>> tex_cmdname('name\nnext') # strip trailing whitespace, also newlines
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# ('name', 'next')
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# >>> tex_cmdname('name_2') # first non-letter terminates
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# ('name', '_2')
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# >>> tex_cmdname('name_2\nnext line') # line-break allowed
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# ('name', '_2\nnext line')
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# >>> tex_cmdname(' next') # leading whitespace is returned
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# (' ', 'next')
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# >>> tex_cmdname('1 2') # whitespace after non-letter is kept
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# ('1', ' 2')
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# >>> tex_cmdname('1\n2\t3') # whitespace after non-letter is kept
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# ('1', '\n2\t3')
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# >>> tex_cmdname('') # empty string
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# ('', '')
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def tex_number(string):
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"""Return leading number literal and remainder of `string`.
|
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>>> tex_number('123.4')
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('123.4', '')
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"""
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m = re.match(r'([0-9.,]*[0-9]+)(.*)', string, re.DOTALL)
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if m is None:
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return '', string
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return m.group(1), m.group(2)
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# Test:
|
||
#
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# >>> tex_number(' 23.4b') # leading whitespace -> no number
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# ('', ' 23.4b')
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# >>> tex_number('23,400/2') # comma separator included
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# ('23,400', '/2')
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# >>> tex_number('23. 4/2') # trailing separator not included
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# ('23', '. 4/2')
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# >>> tex_number('4, 2') # trailing separator not included
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# ('4', ', 2')
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# >>> tex_number('1 000.4')
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# ('1', ' 000.4')
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def tex_token(string):
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"""Return first simple TeX token and remainder of `string`.
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||
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>>> tex_token('\\command{without argument}')
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('\\command', '{without argument}')
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>>> tex_token('or first character')
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('o', 'r first character')
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"""
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m = re.match(r"""((?P<cmd>\\[a-zA-Z]+)\s* # TeX command, skip whitespace
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|(?P<chcmd>\\.) # one-character TeX command
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||
|(?P<ch>.?)) # first character (or empty)
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(?P<remainder>.*$) # remaining part of string
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""", string, re.VERBOSE | re.DOTALL)
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cmd, chcmd, ch, remainder = m.group('cmd', 'chcmd', 'ch', 'remainder')
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return cmd or chcmd or ch, remainder
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# Test:
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||
#
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# >>> tex_token('{opening bracket of group}')
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# ('{', 'opening bracket of group}')
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# >>> tex_token('\\skip whitespace after macro name')
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# ('\\skip', 'whitespace after macro name')
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# >>> tex_token('. but not after single char')
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# ('.', ' but not after single char')
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# >>> tex_token('') # empty string.
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# ('', '')
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# >>> tex_token('\{escaped bracket')
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# ('\\{', 'escaped bracket')
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def tex_group(string):
|
||
"""Return first TeX group or token and remainder of `string`.
|
||
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||
>>> tex_group('{first group} returned without brackets')
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('first group', ' returned without brackets')
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||
|
||
"""
|
||
split_index = 0
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||
nest_level = 0 # level of {{nested} groups}
|
||
escape = False # the next character is escaped (\)
|
||
|
||
if not string.startswith('{'):
|
||
# special case: there is no group, return first token and remainder
|
||
return string[:1], string[1:]
|
||
for c in string:
|
||
split_index += 1
|
||
if escape:
|
||
escape = False
|
||
elif c == '\\':
|
||
escape = True
|
||
elif c == '{':
|
||
nest_level += 1
|
||
elif c == '}':
|
||
nest_level -= 1
|
||
if nest_level == 0:
|
||
break
|
||
else:
|
||
raise MathError('Group without closing bracket!')
|
||
return string[1:split_index-1], string[split_index:]
|
||
|
||
|
||
# >>> tex_group('{} empty group')
|
||
# ('', ' empty group')
|
||
# >>> tex_group('{group with {nested} group} ')
|
||
# ('group with {nested} group', ' ')
|
||
# >>> tex_group('{group with {nested group}} at the end')
|
||
# ('group with {nested group}', ' at the end')
|
||
# >>> tex_group('{{group} {with {{complex }nesting}} constructs}')
|
||
# ('{group} {with {{complex }nesting}} constructs', '')
|
||
# >>> tex_group('{group with \\{escaped\\} brackets}')
|
||
# ('group with \\{escaped\\} brackets', '')
|
||
# >>> tex_group('{group followed by closing bracket}} from outer group')
|
||
# ('group followed by closing bracket', '} from outer group')
|
||
# >>> tex_group('No group? Return first character.')
|
||
# ('N', 'o group? Return first character.')
|
||
# >>> tex_group(' {also whitespace}')
|
||
# (' ', '{also whitespace}')
|
||
|
||
|
||
def tex_token_or_group(string):
|
||
"""Return first TeX group or token and remainder of `string`.
|
||
|
||
>>> tex_token_or_group('\\command{without argument}')
|
||
('\\command', '{without argument}')
|
||
>>> tex_token_or_group('first character')
|
||
('f', 'irst character')
|
||
>>> tex_token_or_group(' also whitespace')
|
||
(' ', 'also whitespace')
|
||
>>> tex_token_or_group('{first group} keep rest')
|
||
('first group', ' keep rest')
|
||
|
||
"""
|
||
arg, remainder = tex_token(string)
|
||
if arg == '{':
|
||
arg, remainder = tex_group(string.lstrip())
|
||
return arg, remainder
|
||
|
||
# >>> tex_token_or_group('\{no group but left bracket')
|
||
# ('\\{', 'no group but left bracket')
|
||
|
||
|
||
def tex_optarg(string):
|
||
"""Return optional argument and remainder.
|
||
|
||
>>> tex_optarg('[optional argument] returned without brackets')
|
||
('optional argument', ' returned without brackets')
|
||
>>> tex_optarg('{empty string, if there is no optional arg}')
|
||
('', '{empty string, if there is no optional arg}')
|
||
|
||
"""
|
||
m = re.match(r"""\s* # leading whitespace
|
||
\[(?P<optarg>(\\]|[^\[\]]|\\])*)\] # [group] without nested groups
|
||
(?P<remainder>.*$)
|
||
""", string, re.VERBOSE | re.DOTALL)
|
||
if m is None and not string.startswith('['):
|
||
return '', string
|
||
try:
|
||
return m.group('optarg'), m.group('remainder')
|
||
except AttributeError:
|
||
raise MathError(f'Could not extract optional argument from "{string}"!')
|
||
|
||
# Test:
|
||
# >>> tex_optarg(' [optional argument] after whitespace')
|
||
# ('optional argument', ' after whitespace')
|
||
# >>> tex_optarg('[missing right bracket')
|
||
# Traceback (most recent call last):
|
||
# ...
|
||
# docutils.utils.math.MathError: Could not extract optional argument from "[missing right bracket"!
|
||
# >>> tex_optarg('[group with [nested group]]')
|
||
# Traceback (most recent call last):
|
||
# ...
|
||
# docutils.utils.math.MathError: Could not extract optional argument from "[group with [nested group]]"!
|
||
|
||
|
||
def parse_latex_math(root, source):
|
||
"""Append MathML conversion of `string` to `node` and return it.
|
||
|
||
>>> parse_latex_math(math(), r'\alpha')
|
||
math(mi('α'))
|
||
>>> parse_latex_math(mrow(), r'x_{n}')
|
||
mrow(msub(mi('x'), mi('n')))
|
||
|
||
"""
|
||
# Normalize white-space:
|
||
string = source # not-yet handled part of source
|
||
node = root # the current "insertion point"
|
||
|
||
# Loop over `string` while changing it.
|
||
while len(string) > 0:
|
||
# Take off first character:
|
||
c, string = string[0], string[1:]
|
||
|
||
if c in ' \n':
|
||
continue # whitespace is ignored in LaTeX math mode
|
||
if c == '\\': # start of a LaTeX macro
|
||
cmdname, string = tex_cmdname(string)
|
||
node, string = handle_cmd(cmdname, node, string)
|
||
elif c in "_^":
|
||
node = handle_script_or_limit(node, c)
|
||
elif c == '{':
|
||
if isinstance(node, MathRow) and node.nchildren == 1:
|
||
# LaTeX takes one arg, MathML node accepts a group
|
||
node.nchildren = None # allow appending until closed by '}'
|
||
else: # wrap group in an <mrow>
|
||
new_node = mrow()
|
||
node.append(new_node)
|
||
node = new_node
|
||
elif c == '}':
|
||
node = node.close()
|
||
elif c == '&':
|
||
new_node = mtd()
|
||
node.close().append(new_node)
|
||
node = new_node
|
||
elif c.isalpha():
|
||
node = node.append(mi(c))
|
||
elif c.isdigit():
|
||
number, string = tex_number(string)
|
||
node = node.append(mn(c+number))
|
||
elif c in anomalous_chars:
|
||
# characters with a special meaning in LaTeX math mode
|
||
# fix spacing before "unary" minus.
|
||
attributes = {}
|
||
if c == '-' and len(node):
|
||
previous_node = node[-1]
|
||
if (previous_node.text and previous_node.text in '([='
|
||
or previous_node.get('class') == 'mathopen'):
|
||
attributes['form'] = 'prefix'
|
||
node = node.append(mo(anomalous_chars[c], **attributes))
|
||
elif c in "/()[]|":
|
||
node = node.append(mo(c, stretchy=False))
|
||
elif c in "+*=<>,.!?`';@":
|
||
node = node.append(mo(c))
|
||
else:
|
||
raise MathError(f'Unsupported character: "{c}"!')
|
||
# TODO: append as <mi>?
|
||
if node is None:
|
||
if not string:
|
||
return root # ignore unbalanced braces
|
||
raise MathError(f'No insertion point for "{string}". '
|
||
f'Unbalanced braces in "{source[:-len(string)]}"?')
|
||
if node.nchildren and len(node) < node.nchildren:
|
||
raise MathError('Last node missing children. Source incomplete?')
|
||
return root
|
||
|
||
# Test:
|
||
|
||
# >>> parse_latex_math(math(), '')
|
||
# math()
|
||
# >>> parse_latex_math(math(), ' \\sqrt{ \\alpha}')
|
||
# math(msqrt(mi('α')))
|
||
# >>> parse_latex_math(math(), '23.4x')
|
||
# math(mn('23.4'), mi('x'))
|
||
# >>> parse_latex_math(math(), '\\sqrt 2 \\ne 3')
|
||
# math(msqrt(mn('2')), mo('≠'), mn('3'))
|
||
# >>> parse_latex_math(math(), '\\sqrt{2 + 3} < 10')
|
||
# math(msqrt(mn('2'), mo('+'), mn('3'), nchildren=3), mo('<'), mn('10'))
|
||
# >>> parse_latex_math(math(), '\\sqrt[3]{2 + 3}')
|
||
# math(mroot(mrow(mn('2'), mo('+'), mn('3'), nchildren=3), mn('3')))
|
||
# >>> parse_latex_math(math(), '\max_x') # function takes limits
|
||
# math(munder(mo('max', movablelimits='true'), mi('x')))
|
||
# >>> parse_latex_math(math(), 'x^j_i') # ensure correct order: base, sub, sup
|
||
# math(msubsup(mi('x'), mi('i'), mi('j')))
|
||
# >>> parse_latex_math(math(), '\int^j_i') # ensure correct order
|
||
# math(msubsup(mo('∫'), mi('i'), mi('j')))
|
||
# >>> parse_latex_math(math(), 'x_{\\alpha}')
|
||
# math(msub(mi('x'), mi('α')))
|
||
# >>> parse_latex_math(math(), 'x_\\text{in}')
|
||
# math(msub(mi('x'), mtext('in')))
|
||
# >>> parse_latex_math(math(), '2⌘')
|
||
# Traceback (most recent call last):
|
||
# docutils.utils.math.MathError: Unsupported character: "⌘"!
|
||
# >>> parse_latex_math(math(), '23}x') # doctest: +ELLIPSIS
|
||
# Traceback (most recent call last):
|
||
# ...
|
||
# docutils.utils.math.MathError: ... Unbalanced braces in "23}"?
|
||
# >>> parse_latex_math(math(), '\\frac{2}')
|
||
# Traceback (most recent call last):
|
||
# ...
|
||
# docutils.utils.math.MathError: Last node missing children. Source incomplete?
|
||
|
||
|
||
def handle_cmd(name, node, string): # noqa: C901 TODO make this less complex
|
||
"""Process LaTeX command `name` followed by `string`.
|
||
|
||
Append result to `node`.
|
||
If needed, parse `string` for command argument.
|
||
Return new current node and remainder of `string`:
|
||
|
||
>>> handle_cmd('hbar', math(), r' \frac')
|
||
(math(mi('ℏ')), ' \\frac')
|
||
>>> handle_cmd('hspace', math(), r'{1ex} (x)')
|
||
(math(mspace(width='1ex')), ' (x)')
|
||
|
||
"""
|
||
|
||
# Token elements
|
||
# ==============
|
||
|
||
# identifier -> <mi>
|
||
|
||
if name in letters:
|
||
new_node = mi(letters[name])
|
||
if name in greek_capitals:
|
||
# upright in "TeX style" but MathML sets them italic ("ISO style").
|
||
# CSS styling does not change the font style in Firefox 78.
|
||
# Use 'mathvariant="normal"'?
|
||
new_node.set('class', 'capital-greek')
|
||
node = node.append(new_node)
|
||
return node, string
|
||
|
||
if name in ordinary:
|
||
# <mi mathvariant="normal"> well supported by Chromium but
|
||
# Firefox 115.5.0 puts additional space around the symbol, e.g.
|
||
# <mi mathvariant="normal">∂</mi><mi>t</mi> looks like ∂ t, not ∂t
|
||
# return node.append(mi(ordinary[name], mathvariant='normal')), string
|
||
return node.append(mi(ordinary[name])), string
|
||
|
||
if name in functions:
|
||
# use <mi> followed by invisible function applicator character
|
||
# (see https://www.w3.org/TR/MathML3/chapter3.html#presm.mi)
|
||
if name == 'operatorname':
|
||
# custom function name, e.g. ``\operatorname{abs}(x)``
|
||
# TODO: \operatorname* -> with limits
|
||
arg, string = tex_token_or_group(string)
|
||
new_node = mi(arg, mathvariant='normal')
|
||
else:
|
||
new_node = mi(functions[name])
|
||
# embellished function names:
|
||
if name == 'varliminf': # \underline\lim
|
||
new_node = munder(new_node, mo('_'))
|
||
elif name == 'varlimsup': # \overline\lim
|
||
new_node = mover(new_node, mo('¯'), accent=False)
|
||
elif name == 'varprojlim': # \underleftarrow\lim
|
||
new_node = munder(new_node, mo('\u2190'))
|
||
elif name == 'varinjlim': # \underrightarrow\lim
|
||
new_node = munder(new_node, mo('\u2192'))
|
||
|
||
node = node.append(new_node)
|
||
# add ApplyFunction when appropriate (not \sin^2(x), say)
|
||
# cf. https://www.w3.org/TR/MathML3/chapter3.html#presm.mi
|
||
if string and string[0] not in ('^', '_'):
|
||
node = node.append(mo('\u2061')) # ⁡
|
||
return node, string
|
||
|
||
if name in modulo_functions:
|
||
(binary, named, parentheses, padding) = modulo_functions[name]
|
||
if binary:
|
||
node = node.append(mo('mod', lspace=padding, rspace=padding))
|
||
return node, string
|
||
# left padding
|
||
if node.in_block():
|
||
padding = '1em'
|
||
node = node.append(mspace(width=padding))
|
||
if parentheses:
|
||
node = node.append(mo('(', stretchy=False))
|
||
if named:
|
||
node = node.append(mi('mod'))
|
||
node = node.append(mspace(width='0.333em'))
|
||
arg, string = tex_token_or_group(string)
|
||
node = parse_latex_math(node, arg)
|
||
if parentheses:
|
||
node = node.append(mo(')', stretchy=False))
|
||
return node, string
|
||
|
||
# font changes or mathematical alphanumeric characters
|
||
|
||
if name in ('boldsymbol', 'pmb'): # \pmb is "poor mans bold"
|
||
new_node = mrow(CLASS='boldsymbol')
|
||
node.append(new_node)
|
||
return new_node, string
|
||
|
||
if name in math_alphabets:
|
||
return handle_math_alphabet(name, node, string)
|
||
|
||
# operator, fence, or separator -> <mo>
|
||
|
||
if name == 'colon': # trailing punctuation, not binary relation
|
||
node = node.append(mo(':', form='postfix', lspace='0', rspace='0.28em'))
|
||
return node, string
|
||
|
||
if name == 'idotsint': # AMS shortcut for ∫︀···∫︀
|
||
node = parse_latex_math(node, r'\int\dotsi\int')
|
||
return node, string
|
||
|
||
if name in thick_operators:
|
||
node = node.append(mo(thick_operators[name], style='font-weight: bold'))
|
||
return node, string
|
||
|
||
if name in small_operators:
|
||
node = node.append(mo(small_operators[name], mathsize='75%'))
|
||
return node, string
|
||
|
||
if name in operators:
|
||
attributes = {}
|
||
if name in movablelimits and string and string[0] in ' _^':
|
||
attributes['movablelimits'] = True
|
||
elif name in ('lvert', 'lVert'):
|
||
attributes['class'] = 'mathopen'
|
||
node = node.append(mo(operators[name], **attributes))
|
||
return node, string
|
||
|
||
if name in bigdelimiters:
|
||
delimiter_attributes = {}
|
||
size = delimiter_sizes[bigdelimiters[name]]
|
||
delimiter, string = tex_token_or_group(string)
|
||
if delimiter not in '()[]/|.':
|
||
try:
|
||
delimiter = stretchables[delimiter.lstrip('\\')]
|
||
except KeyError:
|
||
raise MathError(f'Unsupported "\\{name}" delimiter '
|
||
f'"{delimiter}"!')
|
||
if size:
|
||
delimiter_attributes['maxsize'] = size
|
||
delimiter_attributes['minsize'] = size
|
||
delimiter_attributes['symmetric'] = True
|
||
if name == 'left' or name.endswith('l'):
|
||
row = mrow()
|
||
node.append(row)
|
||
node = row
|
||
if delimiter != '.': # '.' stands for "empty delimiter"
|
||
node.append(mo(delimiter, **delimiter_attributes))
|
||
if name == 'right' or name.endswith('r'):
|
||
node = node.close()
|
||
return node, string
|
||
|
||
if name == 'not':
|
||
# negation: LaTeX just overlays next symbol with "/".
|
||
arg, string = tex_token(string)
|
||
if arg == '{':
|
||
return node, '{\\not ' + string
|
||
if arg.startswith('\\'): # LaTeX macro
|
||
try:
|
||
arg = operators[arg[1:]]
|
||
except KeyError:
|
||
raise MathError(rf'"\not" cannot negate: "{arg}"!')
|
||
arg = unicodedata.normalize('NFC', arg+'\u0338')
|
||
node = node.append(mo(arg))
|
||
return node, string
|
||
|
||
# arbitrary text (usually comments) -> <mtext>
|
||
if name in ('text', 'mbox', 'textrm'):
|
||
arg, string = tex_token_or_group(string)
|
||
parts = arg.split('$') # extract inline math
|
||
for i, part in enumerate(parts):
|
||
if i % 2 == 0: # i is even
|
||
# LaTeX keeps whitespace in, e.g., ``\text{ foo }``,
|
||
# <mtext> displays only internal whitespace.
|
||
# → replace marginal whitespace with NBSP
|
||
part = re.sub('(^[ \n]|[ \n]$)', '\u00a0', part)
|
||
node = node.append(mtext(part))
|
||
else:
|
||
parse_latex_math(node, part)
|
||
return node, string
|
||
|
||
# horizontal space -> <mspace>
|
||
if name in spaces:
|
||
node = node.append(mspace(width='%s'%spaces[name]))
|
||
return node, string
|
||
|
||
if name in ('hspace', 'mspace'):
|
||
arg, string = tex_group(string)
|
||
if arg.endswith('mu'):
|
||
# unit "mu" (1mu=1/18em) not supported by MathML
|
||
arg = '%sem' % (float(arg[:-2])/18)
|
||
node = node.append(mspace(width='%s'%arg))
|
||
return node, string
|
||
|
||
if name == 'phantom':
|
||
new_node = mphantom()
|
||
node.append(new_node)
|
||
return new_node, string
|
||
|
||
if name == 'boxed':
|
||
# CSS padding is broken in Firefox 115.6.0esr
|
||
# therefore we still need the deprecated <menclose> element
|
||
new_node = menclose(notation='box', CLASS='boxed')
|
||
node.append(new_node)
|
||
return new_node, string
|
||
|
||
# Complex elements (Layout schemata)
|
||
# ==================================
|
||
|
||
if name == 'sqrt':
|
||
radix, string = tex_optarg(string)
|
||
if radix:
|
||
indexnode = mrow()
|
||
new_node = mroot(indexnode, switch=True)
|
||
parse_latex_math(indexnode, radix)
|
||
indexnode.close()
|
||
else:
|
||
new_node = msqrt()
|
||
node.append(new_node)
|
||
return new_node, string
|
||
|
||
if name in fractions:
|
||
attributes = fractions[name]
|
||
if name == 'cfrac':
|
||
optarg, string = tex_optarg(string)
|
||
optargs = {'l': 'left', 'r': 'right'}
|
||
if optarg in optargs:
|
||
attributes = attributes.copy()
|
||
attributes['numalign'] = optargs[optarg] # "numalign" is deprecated
|
||
attributes['class'] += ' numalign-' + optargs[optarg]
|
||
new_node = frac = mfrac(**attributes)
|
||
if name.endswith('binom'):
|
||
new_node = mrow(mo('('), new_node, mo(')'), CLASS='binom')
|
||
new_node.nchildren = 3
|
||
node.append(new_node)
|
||
return frac, string
|
||
|
||
if name == '\\': # end of a row
|
||
entry = mtd()
|
||
new_node = mtr(entry)
|
||
node.close().close().append(new_node)
|
||
return entry, string
|
||
|
||
if name in accents:
|
||
accent_node = mo(accents[name], stretchy=False)
|
||
# mi() would be simpler, but semantically wrong
|
||
# --- https://w3c.github.io/mathml-core/#operator-fence-separator-or-accent-mo
|
||
if name == 'vec':
|
||
accent_node.set('scriptlevel', '+1') # scale down arrow
|
||
new_node = mover(accent_node, accent=True, switch=True)
|
||
node.append(new_node)
|
||
return new_node, string
|
||
|
||
if name in over:
|
||
# set "accent" to False (otherwise dots on i and j are dropped)
|
||
# but to True on accent node get "textstyle" (full size) symbols on top
|
||
new_node = mover(mo(over[name][0], accent=True),
|
||
switch=True, accent=False)
|
||
node.append(new_node)
|
||
return new_node, string
|
||
|
||
if name == 'overset':
|
||
new_node = mover(switch=True)
|
||
node.append(new_node)
|
||
return new_node, string
|
||
|
||
if name in under:
|
||
new_node = munder(mo(under[name][0]), switch=True)
|
||
node.append(new_node)
|
||
return new_node, string
|
||
|
||
if name == 'underset':
|
||
new_node = munder(switch=True)
|
||
node.append(new_node)
|
||
return new_node, string
|
||
|
||
if name in ('xleftarrow', 'xrightarrow'):
|
||
subscript, string = tex_optarg(string)
|
||
base = mo(operators['long'+name[1:]])
|
||
if subscript:
|
||
new_node = munderover(base)
|
||
sub_node = parse_latex_math(mrow(), subscript)
|
||
if len(sub_node) == 1:
|
||
sub_node = sub_node[0]
|
||
new_node.append(sub_node)
|
||
else:
|
||
new_node = mover(base)
|
||
node.append(new_node)
|
||
return new_node, string
|
||
|
||
if name in layout_styles: # 'displaystyle', 'textstyle', ...
|
||
if len(node) > 0:
|
||
raise MathError(rf'Declaration "\{name}" must be first command '
|
||
'in a group!')
|
||
for k, v in layout_styles[name].items():
|
||
node.set(k, v)
|
||
return node, string
|
||
|
||
if name.endswith('limits'):
|
||
arg, remainder = tex_token(string)
|
||
if arg in '_^': # else ignore
|
||
string = remainder
|
||
node = handle_script_or_limit(node, arg, limits=name)
|
||
return node, string
|
||
|
||
# Environments
|
||
|
||
if name == 'begin':
|
||
return begin_environment(node, string)
|
||
|
||
if name == 'end':
|
||
return end_environment(node, string)
|
||
|
||
raise MathError(rf'Unknown LaTeX command "\{name}".')
|
||
|
||
# >>> handle_cmd('left', math(), '[a\\right]')
|
||
# (mrow(mo('[')), 'a\\right]')
|
||
# >>> handle_cmd('left', math(), '. a)') # empty \left
|
||
# (mrow(), ' a)')
|
||
# >>> handle_cmd('left', math(), '\\uparrow a)') # cmd
|
||
# (mrow(mo('↑')), 'a)')
|
||
# >>> handle_cmd('not', math(), '\\equiv \\alpha)') # cmd
|
||
# (math(mo('≢')), '\\alpha)')
|
||
# >>> handle_cmd('text', math(), '{ for } i>0') # group
|
||
# (math(mtext('\xa0for\xa0')), ' i>0')
|
||
# >>> handle_cmd('text', math(), '{B}T') # group
|
||
# (math(mtext('B')), 'T')
|
||
# >>> handle_cmd('text', math(), '{number of apples}}') # group
|
||
# (math(mtext('number of apples')), '}')
|
||
# >>> handle_cmd('text', math(), 'i \\sin(x)') # single char
|
||
# (math(mtext('i')), ' \\sin(x)')
|
||
# >>> handle_cmd(' ', math(), ' next') # inter word space
|
||
# (math(mspace(width='0.25em')), ' next')
|
||
# >>> handle_cmd('\n', math(), '\nnext') # inter word space
|
||
# (math(mspace(width='0.25em')), '\nnext')
|
||
# >>> handle_cmd('sin', math(), '(\\alpha)')
|
||
# (math(mi('sin'), mo('\u2061')), '(\\alpha)')
|
||
# >>> handle_cmd('sin', math(), ' \\alpha')
|
||
# (math(mi('sin'), mo('\u2061')), ' \\alpha')
|
||
# >>> handle_cmd('operatorname', math(), '{abs}(x)')
|
||
# (math(mi('abs', mathvariant='normal'), mo('\u2061')), '(x)')
|
||
# >>> handle_cmd('overline', math(), '{981}')
|
||
# (mover(mo('_', accent='true'), switch=True, accent='false'), '{981}')
|
||
# >>> handle_cmd('bar', math(), '{x}')
|
||
# (mover(mo('ˉ', stretchy='false'), switch=True, accent='true'), '{x}')
|
||
# >>> handle_cmd('xleftarrow', math(), r'[\alpha]{10}')
|
||
# (munderover(mo('⟵'), mi('α')), '{10}')
|
||
# >>> handle_cmd('xleftarrow', math(), r'[\alpha=5]{10}')
|
||
# (munderover(mo('⟵'), mrow(mi('α'), mo('='), mn('5'))), '{10}')
|
||
# >>> handle_cmd('left', math(), '< a)')
|
||
# Traceback (most recent call last):
|
||
# docutils.utils.math.MathError: Unsupported "\left" delimiter "<"!
|
||
# >>> handle_cmd('not', math(), '{< b} c') # LaTeX ignores the braces, too.
|
||
# (math(), '{\\not < b} c')
|
||
|
||
|
||
def handle_math_alphabet(name, node, string):
|
||
attributes = {}
|
||
if name == 'mathscr':
|
||
attributes['class'] = 'mathscr'
|
||
arg, string = tex_token_or_group(string)
|
||
# Shortcut for text arg like \mathrm{out} with more than one letter:
|
||
if name == 'mathrm' and arg.isalpha() and len(arg) > 1:
|
||
node = node.append(mi(arg)) # <mi> defaults to "normal" font
|
||
return node, string
|
||
# Parse into an <mrow>
|
||
container = mrow(**attributes)
|
||
node.append(container)
|
||
parse_latex_math(container, arg)
|
||
key = name.replace('mathscr', 'mathcal').replace('mathbfsfit', 'mathsfbfit')
|
||
a2ch = getattr(mathalphabet2unichar, key, {})
|
||
for subnode in container.iter():
|
||
if isinstance(subnode, mn):
|
||
# a number may consist of more than one digit
|
||
subnode.text = ''.join(a2ch.get(ch, ch) for ch in subnode.text)
|
||
elif isinstance(subnode, mi):
|
||
# don't convert multi-letter identifiers (functions)
|
||
subnode.text = a2ch.get(subnode.text, subnode.text)
|
||
if name == 'mathrm' and subnode.text.isalpha():
|
||
subnode.set('mathvariant', 'normal')
|
||
return container.close(), string
|
||
|
||
# >>> handle_math_alphabet('mathrm', math(), '\\alpha')
|
||
# (math(mi('α', mathvariant='normal')), '')
|
||
# >>> handle_math_alphabet('mathbb', math(), '{R} = 3')
|
||
# (math(mi('ℝ')), ' = 3')
|
||
# >>> handle_math_alphabet('mathcal', math(), '{F = 3}')
|
||
# (math(mrow(mi('ℱ'), mo('='), mn('3'), nchildren=3)), '')
|
||
# >>> handle_math_alphabet('mathrm', math(), '{out} = 3') # drop <mrow>
|
||
# (math(mi('out')), ' = 3')
|
||
#
|
||
# Single letters in \mathrm require "mathvariant='normal'":
|
||
# >>> handle_math_alphabet('mathrm', math(), '{V = 3}') # doctest: +ELLIPSIS
|
||
# (math(mrow(mi('V', mathvariant='normal'), mo('='), mn('3'), ...)), '')
|
||
|
||
|
||
def handle_script_or_limit(node, c, limits=''):
|
||
"""Append script or limit element to `node`."""
|
||
child = node.pop()
|
||
if limits == 'limits':
|
||
child.set('movablelimits', 'false')
|
||
elif (limits == 'movablelimits'
|
||
or getattr(child, 'text', '') in movablelimits):
|
||
child.set('movablelimits', 'true')
|
||
|
||
if c == '_':
|
||
if isinstance(child, mover):
|
||
new_node = munderover(*child, switch=True)
|
||
elif isinstance(child, msup):
|
||
new_node = msubsup(*child, switch=True)
|
||
elif (limits in ('limits', 'movablelimits')
|
||
or limits == '' and child.get('movablelimits', None)):
|
||
new_node = munder(child)
|
||
else:
|
||
new_node = msub(child)
|
||
elif c == '^':
|
||
if isinstance(child, munder):
|
||
new_node = munderover(*child)
|
||
elif isinstance(child, msub):
|
||
new_node = msubsup(*child)
|
||
elif (limits in ('limits', 'movablelimits')
|
||
or limits == '' and child.get('movablelimits', None)):
|
||
new_node = mover(child)
|
||
else:
|
||
new_node = msup(child)
|
||
node.append(new_node)
|
||
return new_node
|
||
|
||
|
||
def begin_environment(node, string):
|
||
name, string = tex_group(string)
|
||
if name in matrices:
|
||
left_delimiter = matrices[name][0]
|
||
attributes = {}
|
||
if left_delimiter:
|
||
wrapper = mrow(mo(left_delimiter))
|
||
if name == 'cases':
|
||
wrapper = mrow(mo(left_delimiter, rspace='0.17em'))
|
||
attributes['columnalign'] = 'left'
|
||
attributes['class'] = 'cases'
|
||
node.append(wrapper)
|
||
node = wrapper
|
||
elif name == 'smallmatrix':
|
||
attributes['rowspacing'] = '0.02em'
|
||
attributes['columnspacing'] = '0.333em'
|
||
attributes['scriptlevel'] = '1'
|
||
elif name == 'aligned':
|
||
attributes['class'] = 'ams-align'
|
||
# TODO: array, aligned & alignedat take an optional [t], [b], or [c].
|
||
entry = mtd()
|
||
node.append(mtable(mtr(entry), **attributes))
|
||
node = entry
|
||
else:
|
||
raise MathError(f'Environment "{name}" not supported!')
|
||
return node, string
|
||
|
||
|
||
def end_environment(node, string):
|
||
name, string = tex_group(string)
|
||
if name in matrices:
|
||
node = node.close().close().close() # close: mtd, mdr, mtable
|
||
right_delimiter = matrices[name][1]
|
||
if right_delimiter:
|
||
node = node.append(mo(right_delimiter))
|
||
node = node.close()
|
||
elif name == 'cases':
|
||
node = node.close()
|
||
else:
|
||
raise MathError(f'Environment "{name}" not supported!')
|
||
return node, string
|
||
|
||
|
||
# Return the number of "equation_columns" in `code_lines`. cf. "alignat"
|
||
# in http://mirror.ctan.org/macros/latex/required/amsmath/amsldoc.pdf
|
||
def tex_equation_columns(rows):
|
||
tabs = max(row.count('&') - row.count(r'\&') for row in rows)
|
||
if tabs == 0:
|
||
return 0
|
||
return int(tabs/2 + 1)
|
||
|
||
# >>> tex_equation_columns(['a = b'])
|
||
# 0
|
||
# >>> tex_equation_columns(['a &= b'])
|
||
# 1
|
||
# >>> tex_equation_columns(['a &= b & a \in S'])
|
||
# 2
|
||
# >>> tex_equation_columns(['a &= b & c &= d'])
|
||
# 2
|
||
|
||
|
||
# Return dictionary with attributes to style an <mtable> as align environment:
|
||
# Not used with HTML. Replaced by CSS rule for "mtable.ams-align" in
|
||
# "minimal.css" as "columnalign" is disregarded by Chromium and webkit.
|
||
def align_attributes(rows):
|
||
atts = {'class': 'ams-align',
|
||
'displaystyle': True}
|
||
# get maximal number of non-escaped "next column" markup characters:
|
||
tabs = max(row.count('&') - row.count(r'\&') for row in rows)
|
||
if tabs:
|
||
aligns = ['right', 'left'] * tabs
|
||
spacing = ['0', '2em'] * tabs
|
||
atts['columnalign'] = ' '.join(aligns[:tabs+1])
|
||
atts['columnspacing'] = ' '.join(spacing[:tabs])
|
||
return atts
|
||
|
||
# >>> align_attributes(['a = b'])
|
||
# {'class': 'ams-align', 'displaystyle': True}
|
||
# >>> align_attributes(['a &= b'])
|
||
# {'class': 'ams-align', 'displaystyle': True, 'columnalign': 'right left', 'columnspacing': '0'}
|
||
# >>> align_attributes(['a &= b & a \in S'])
|
||
# {'class': 'ams-align', 'displaystyle': True, 'columnalign': 'right left right', 'columnspacing': '0 2em'}
|
||
# >>> align_attributes(['a &= b & c &= d'])
|
||
# {'class': 'ams-align', 'displaystyle': True, 'columnalign': 'right left right left', 'columnspacing': '0 2em 0'}
|
||
# >>> align_attributes([r'a &= b & c &= d \& e'])
|
||
# {'class': 'ams-align', 'displaystyle': True, 'columnalign': 'right left right left', 'columnspacing': '0 2em 0'}
|
||
# >>> align_attributes([r'a &= b & c &= d & e'])
|
||
# {'class': 'ams-align', 'displaystyle': True, 'columnalign': 'right left right left right', 'columnspacing': '0 2em 0 2em'}
|
||
|
||
|
||
def tex2mathml(tex_math, as_block=False):
|
||
"""Return string with MathML code corresponding to `tex_math`.
|
||
|
||
Set `as_block` to ``True`` for displayed formulas.
|
||
"""
|
||
# Set up tree
|
||
math_tree = math(xmlns='http://www.w3.org/1998/Math/MathML')
|
||
node = math_tree
|
||
if as_block:
|
||
math_tree.set('display', 'block')
|
||
rows = toplevel_code(tex_math).split(r'\\')
|
||
if len(rows) > 1:
|
||
# emulate "align*" environment with a math table
|
||
node = mtd()
|
||
math_tree.append(mtable(mtr(node), CLASS='ams-align',
|
||
displaystyle=True))
|
||
parse_latex_math(node, tex_math)
|
||
math_tree.indent_xml()
|
||
return math_tree.toxml()
|
||
|
||
# >>> print(tex2mathml('3'))
|
||
# <math xmlns="http://www.w3.org/1998/Math/MathML">
|
||
# <mn>3</mn>
|
||
# </math>
|
||
# >>> print(tex2mathml('3', as_block=True))
|
||
# <math xmlns="http://www.w3.org/1998/Math/MathML" display="block">
|
||
# <mn>3</mn>
|
||
# </math>
|
||
# >>> print(tex2mathml(r'a & b \\ c & d', as_block=True))
|
||
# <math xmlns="http://www.w3.org/1998/Math/MathML" display="block">
|
||
# <mtable class="ams-align" displaystyle="true">
|
||
# <mtr>
|
||
# <mtd>
|
||
# <mi>a</mi>
|
||
# </mtd>
|
||
# <mtd>
|
||
# <mi>b</mi>
|
||
# </mtd>
|
||
# </mtr>
|
||
# <mtr>
|
||
# <mtd>
|
||
# <mi>c</mi>
|
||
# </mtd>
|
||
# <mtd>
|
||
# <mi>d</mi>
|
||
# </mtd>
|
||
# </mtr>
|
||
# </mtable>
|
||
# </math>
|
||
# >>> print(tex2mathml(r'a \\ b', as_block=True))
|
||
# <math xmlns="http://www.w3.org/1998/Math/MathML" display="block">
|
||
# <mtable class="ams-align" displaystyle="true">
|
||
# <mtr>
|
||
# <mtd>
|
||
# <mi>a</mi>
|
||
# </mtd>
|
||
# </mtr>
|
||
# <mtr>
|
||
# <mtd>
|
||
# <mi>b</mi>
|
||
# </mtd>
|
||
# </mtr>
|
||
# </mtable>
|
||
# </math>
|
||
|
||
|
||
# TODO: look up more symbols from tr25, e.g.
|
||
#
|
||
#
|
||
# Table 2.8 Using Vertical Line or Solidus Overlay
|
||
# some of the negated forms of mathematical relations that can only be
|
||
# encoded by using either U+0338 COMBINING LONG SOLIDUS OVERLAY or U+20D2
|
||
# COMBINING LONG VERTICAL LINE OVERLAY . (For issues with using 0338 in
|
||
# MathML, see Section 3.2.7, Combining Marks.
|
||
#
|
||
# Table 2.9 Variants of Mathematical Symbols using VS1?
|
||
#
|
||
# Sequence Description
|
||
# 0030 + VS1 DIGIT ZERO - short diagonal stroke form
|
||
# 2205 + VS1 EMPTY SET - zero with long diagonal stroke overlay form
|
||
# 2229 + VS1 INTERSECTION - with serifs
|
||
# 222A + VS1 UNION - with serifs
|
||
# 2268 + VS1 LESS-THAN BUT NOT EQUAL TO - with vertical stroke
|
||
# 2269 + VS1 GREATER-THAN BUT NOT EQUAL TO - with vertical stroke
|
||
# 2272 + VS1 LESS-THAN OR EQUIVALENT TO - following the slant of the lower leg
|
||
# 2273 + VS1 GREATER-THAN OR EQUIVALENT TO - following the slant of the lower leg
|
||
# 228A + VS1 SUBSET OF WITH NOT EQUAL TO - variant with stroke through bottom members
|
||
# 228B + VS1 SUPERSET OF WITH NOT EQUAL TO - variant with stroke through bottom members
|
||
# 2293 + VS1 SQUARE CAP - with serifs
|
||
# 2294 + VS1 SQUARE CUP - with serifs
|
||
# 2295 + VS1 CIRCLED PLUS - with white rim
|
||
# 2297 + VS1 CIRCLED TIMES - with white rim
|
||
# 229C + VS1 CIRCLED EQUALS - equal sign inside and touching the circle
|
||
# 22DA + VS1 LESS-THAN slanted EQUAL TO OR GREATER-THAN
|
||
# 22DB + VS1 GREATER-THAN slanted EQUAL TO OR LESS-THAN
|
||
# 2A3C + VS1 INTERIOR PRODUCT - tall variant with narrow foot
|
||
# 2A3D + VS1 RIGHTHAND INTERIOR PRODUCT - tall variant with narrow foot
|
||
# 2A9D + VS1 SIMILAR OR LESS-THAN - following the slant of the upper leg
|
||
# 2A9E + VS1 SIMILAR OR GREATER-THAN - following the slant of the upper leg
|
||
# 2AAC + VS1 SMALLER THAN OR slanted EQUAL
|
||
# 2AAD + VS1 LARGER THAN OR slanted EQUAL
|
||
# 2ACB + VS1 SUBSET OF ABOVE NOT EQUAL TO - variant with stroke through bottom members
|
||
# 2ACC + VS1 SUPERSET OF ABOVE NOT EQUAL TO - variant with stroke through bottom members
|