##// END OF EJS Templates
Make copy of notebook node object to make sure the source doesn't get modified
Make copy of notebook node object to make sure the source doesn't get modified

File last commit:

r11088:a50cba11
r11375:410cedc0
Show More
latex.py
115 lines | 3.6 KiB | text/x-python | PythonLexer
"""Latex filters.
Module of useful filters for processing Latex within Jinja latex templates.
"""
#-----------------------------------------------------------------------------
# Copyright (c) 2013, the IPython Development Team.
#
# Distributed under the terms of the Modified BSD License.
#
# The full license is in the file COPYING.txt, distributed with this software.
#-----------------------------------------------------------------------------
#-----------------------------------------------------------------------------
# Imports
#-----------------------------------------------------------------------------
import re
#-----------------------------------------------------------------------------
# Globals and constants
#-----------------------------------------------------------------------------
#Latex substitutions for escaping latex.
LATEX_SUBS = (
(re.compile('\033\[[0-9;]+m'),''), # handle console escapes
(re.compile(r'\\'), r'\\textbackslash'),
(re.compile(r'([{}_#%&$])'), r'\\\1'),
(re.compile(r'~'), r'\~{}'),
(re.compile(r'\^'), r'\^{}'),
(re.compile(r'"'), r"''"),
(re.compile(r'\.\.\.+'), r'\\ldots'),
)
#-----------------------------------------------------------------------------
# Functions
#-----------------------------------------------------------------------------
__all__ = [
'escape_latex',
'rm_math_space'
]
def escape_latex(text):
"""
Escape characters that may conflict with latex.
Parameters
----------
text : str
Text containing characters that may conflict with Latex
"""
return_text = text
for pattern, replacement in LATEX_SUBS:
return_text = pattern.sub(replacement, return_text)
return return_text
def rm_math_space(text):
"""
Remove the space between latex math commands and enclosing $ symbols.
This filter is important because latex isn't as flexible as the notebook
front end when it comes to flagging math using ampersand symbols.
Parameters
----------
text : str
Text to filter.
"""
# First, scan through the markdown looking for $. If
# a $ symbol is found, without a preceding \, assume
# it is the start of a math block. UNLESS that $ is
# not followed by another within two math_lines.
math_regions = []
math_lines = 0
within_math = False
math_start_index = 0
ptext = ''
last_character = ""
skip = False
for index, char in enumerate(text):
#Make sure the character isn't preceeded by a backslash
if (char == "$" and last_character != "\\"):
# Close the math region if this is an ending $
if within_math:
within_math = False
skip = True
ptext = ptext+'$'+text[math_start_index+1:index].strip()+'$'
math_regions.append([math_start_index, index+1])
else:
# Start a new math region
within_math = True
math_start_index = index
math_lines = 0
# If we are in a math region, count the number of lines parsed.
# Cancel the math region if we find two line breaks!
elif char == "\n":
if within_math:
math_lines += 1
if math_lines > 1:
within_math = False
ptext = ptext+text[math_start_index:index]
# Remember the last character so we can easily watch
# for backslashes
last_character = char
if not within_math and not skip:
ptext = ptext+char
if skip:
skip = False
return ptext