36 lines
991 B
Python
36 lines
991 B
Python
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from sympy.external import import_module
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from sympy.utilities.decorator import doctest_depends_on
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from .errors import LaTeXParsingError # noqa
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@doctest_depends_on(modules=('antlr4',))
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def parse_latex(s):
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r"""Converts the string ``s`` to a SymPy ``Expr``
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Parameters
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==========
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s : str
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The LaTeX string to parse. In Python source containing LaTeX,
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*raw strings* (denoted with ``r"``, like this one) are preferred,
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as LaTeX makes liberal use of the ``\`` character, which would
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trigger escaping in normal Python strings.
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Examples
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========
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>>> from sympy.parsing.latex import parse_latex
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>>> expr = parse_latex(r"\frac {1 + \sqrt {\a}} {\b}")
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>>> expr
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(sqrt(a) + 1)/b
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>>> expr.evalf(4, subs=dict(a=5, b=2))
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1.618
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"""
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_latex = import_module(
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'sympy.parsing.latex._parse_latex_antlr',
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import_kwargs={'fromlist': ['X']})
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if _latex is not None:
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return _latex.parse_latex(s)
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