Das deutsche Python-Forum

#! /usr/bin/env python
# -*- coding: utf8 -*-
import os
import sys

#from ipHelp import IPS, ip_syshook
#ip_syshook(0) # personal IPython debug stuff

# inspired by the forum thread:
#http://www.matheplanet.com/matheplanet/nuke/html/viewtopic.php?post_id=729017&topic=94327

# pretty much taken from eqtexsvg.py by Julien Vitard (as part of inkscape)
# therefore the whole script is licenced under the terms of the
# GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.

# needs: latex, dvipng, pngcrush

def createPNG(symbolText, finalpng_filename):

    base_dir="./"
    latex_file = os.path.join(base_dir, "eq.tex")
    aux_file = os.path.join(base_dir, "eq.aux")
    log_file = os.path.join(base_dir, "eq.log")
    dvi_file = os.path.join(base_dir, "eq.dvi")
    out_file = os.path.join(base_dir, "eq.out")
    png_file = os.path.join(base_dir, "eq.png")

    def clean():
        os.remove(latex_file)
        os.remove(aux_file)
        os.remove(log_file)
        os.remove(dvi_file)
        os.remove(out_file)

    def create_equation_tex(filename, equation):
        tex = open(filename, 'w')
        tex.write("""%% processed with kilehilfe.py
\\documentclass{article}
\\usepackage{amsmath}
\\usepackage{amssymb}
\\usepackage{amsfonts}

\\thispagestyle{empty}
\\begin{document}
    """)

        # maybe you will have to add some packages above
        tex.write(equation)
        tex.write("\n\\end{document}\n")
        tex.close()

    create_equation_tex(latex_file, symbolText)
    #os.system('cd ' + base_dir)
    os.system('latex -output-directory=' + base_dir + ' -halt-on-error ' +
                                                latex_file + ' > ' + out_file)
    try:
        os.stat(dvi_file)
    except OSError:
        print >>sys.stderr, "invalid LaTeX input:"
        print >>sys.stderr, symbolText
        print >>sys.stderr, "temporary files were left in:", base_dir
        sys.exit(1)

    os.system('dvipng -T tight -o ' +png_file + ' ' + dvi_file)
    # -T tight cuts off all the empty blank space arround the symbol

    if symbolText[0]+symbolText[-1]=="$$":
       symbolText=symbolText[1:-1] # "$\aplha$" -> "\alpha"

    ## maybe pngcrush could be made obsolate by using this:
    ## (manipultating png-metadata with python)
    ##http://blog.modp.com/2007/08/python-pil-and-png-metadata-take-2.html
    cmd = 'pngcrush -text b "Command" "%s" %s %s ' %(symbolText, png_file,
                                                    finalpng_filename)
    os.system(cmd)
    clean()

###
# main program:

#render a symbol for every element of the list
#using raw strings (r'my_raw_sting') to prevent python from
#interpreting the backslash-character by itself
symbolList=[r'$\dot{q_1}$', r'$\ddot{q_1}$', r'$\dot{q_2}$', r'$\ddot{q_2}$',
            r'$\tilde{q_2}$', r'$\dot{\tilde{q_2}}$', r'$\stackrel{!}{=}$',
            r'$\mathbf{M}$', r'$\text{abc}$', ]


# now iterate over the list
for i, symb in enumerate(symbolList):
    createPNG(symb, "symb%03d.png" % i)