| r""" |
| |
| .. redirect-from:: /tutorials/text/pgf |
| |
| .. _pgf: |
| |
| ************************************************************ |
| Text rendering with XeLaTeX/LuaLaTeX via the ``pgf`` backend |
| ************************************************************ |
| |
| Using the ``pgf`` backend, Matplotlib can export figures as pgf drawing |
| commands that can be processed with pdflatex, xelatex or lualatex. XeLaTeX and |
| LuaLaTeX have full Unicode support and can use any font that is installed in |
| the operating system, making use of advanced typographic features of OpenType, |
| AAT and Graphite. Pgf pictures created by ``plt.savefig('figure.pgf')`` |
| can be embedded as raw commands in LaTeX documents. Figures can also be |
| directly compiled and saved to PDF with ``plt.savefig('figure.pdf')`` by |
| switching the backend :: |
| |
| matplotlib.use('pgf') |
| |
| or by explicitly requesting the use of the ``pgf`` backend :: |
| |
| plt.savefig('figure.pdf', backend='pgf') |
| |
| or by registering it for handling pdf output :: |
| |
| from matplotlib.backends.backend_pgf import FigureCanvasPgf |
| matplotlib.backend_bases.register_backend('pdf', FigureCanvasPgf) |
| |
| The last method allows you to keep using regular interactive backends and to |
| save xelatex, lualatex or pdflatex compiled PDF files from the graphical user |
| interface. |
| |
| Matplotlib's pgf support requires a recent LaTeX_ installation that includes |
| the TikZ/PGF packages (such as TeXLive_), preferably with XeLaTeX or LuaLaTeX |
| installed. If either pdftocairo or ghostscript is present on your system, |
| figures can optionally be saved to PNG images as well. The executables |
| for all applications must be located on your :envvar:`PATH`. |
| |
| `.rcParams` that control the behavior of the pgf backend: |
| |
| ================= ===================================================== |
| Parameter Documentation |
| ================= ===================================================== |
| pgf.preamble Lines to be included in the LaTeX preamble |
| pgf.rcfonts Setup fonts from rc params using the fontspec package |
| pgf.texsystem Either "xelatex" (default), "lualatex" or "pdflatex" |
| ================= ===================================================== |
| |
| .. note:: |
| |
| TeX defines a set of special characters, such as:: |
| |
| # $ % & ~ _ ^ \ { } |
| |
| Generally, these characters must be escaped correctly. For convenience, |
| some characters (_, ^, %) are automatically escaped outside of math |
| environments. Other characters are not escaped as they are commonly needed |
| in actual TeX expressions. However, one can configure TeX to treat them as |
| "normal" characters (known as "catcode 12" to TeX) via a custom preamble, |
| such as:: |
| |
| plt.rcParams["pgf.preamble"] = ( |
| r"\AtBeginDocument{\catcode`\&=12\catcode`\#=12}") |
| |
| .. _pgf-rcfonts: |
| |
| |
| Multi-Page PDF Files |
| ==================== |
| |
| The pgf backend also supports multipage pdf files using |
| `~.backend_pgf.PdfPages` |
| |
| .. code-block:: python |
| |
| from matplotlib.backends.backend_pgf import PdfPages |
| import matplotlib.pyplot as plt |
| |
| with PdfPages('multipage.pdf', metadata={'author': 'Me'}) as pdf: |
| |
| fig1, ax1 = plt.subplots() |
| ax1.plot([1, 5, 3]) |
| pdf.savefig(fig1) |
| |
| fig2, ax2 = plt.subplots() |
| ax2.plot([1, 5, 3]) |
| pdf.savefig(fig2) |
| |
| |
| Font specification |
| ================== |
| |
| The fonts used for obtaining the size of text elements or when compiling |
| figures to PDF are usually defined in the `.rcParams`. You can also use the |
| LaTeX default Computer Modern fonts by clearing the lists for :rc:`font.serif`, |
| :rc:`font.sans-serif` or :rc:`font.monospace`. Please note that the glyph |
| coverage of these fonts is very limited. If you want to keep the Computer |
| Modern font face but require extended Unicode support, consider installing the |
| `Computer Modern Unicode`__ fonts *CMU Serif*, *CMU Sans Serif*, etc. |
| |
| __ https://sourceforge.net/projects/cm-unicode/ |
| |
| When saving to ``.pgf``, the font configuration Matplotlib used for the |
| layout of the figure is included in the header of the text file. |
| |
| .. literalinclude:: /gallery/userdemo/pgf_fonts.py |
| :end-before: fig.savefig |
| |
| |
| .. _pgf-preamble: |
| |
| Custom preamble |
| =============== |
| |
| Full customization is possible by adding your own commands to the preamble. |
| Use :rc:`pgf.preamble` if you want to configure the math fonts, |
| using ``unicode-math`` for example, or for loading additional packages. Also, |
| if you want to do the font configuration yourself instead of using the fonts |
| specified in the rc parameters, make sure to disable :rc:`pgf.rcfonts`. |
| |
| .. only:: html |
| |
| .. literalinclude:: /gallery/userdemo/pgf_preamble_sgskip.py |
| :end-before: fig.savefig |
| |
| .. only:: latex |
| |
| .. literalinclude:: /gallery/userdemo/pgf_preamble_sgskip.py |
| :end-before: import matplotlib.pyplot as plt |
| |
| |
| .. _pgf-texsystem: |
| |
| Choosing the TeX system |
| ======================= |
| |
| The TeX system to be used by Matplotlib is chosen by :rc:`pgf.texsystem`. |
| Possible values are ``'xelatex'`` (default), ``'lualatex'`` and ``'pdflatex'``. |
| Please note that when selecting pdflatex, the fonts and Unicode handling must |
| be configured in the preamble. |
| |
| .. literalinclude:: /gallery/userdemo/pgf_texsystem.py |
| :end-before: fig.savefig |
| |
| |
| .. _pgf-troubleshooting: |
| |
| Troubleshooting |
| =============== |
| |
| * Please note that the TeX packages found in some Linux distributions and |
| MiKTeX installations are dramatically outdated. Make sure to update your |
| package catalog and upgrade or install a recent TeX distribution. |
| |
| * On Windows, the :envvar:`PATH` environment variable may need to be modified |
| to include the directories containing the latex, dvipng and ghostscript |
| executables. See :ref:`environment-variables` and |
| :ref:`setting-windows-environment-variables` for details. |
| |
| * Sometimes the font rendering in figures that are saved to png images is |
| very bad. This happens when the pdftocairo tool is not available and |
| ghostscript is used for the pdf to png conversion. |
| |
| * Make sure what you are trying to do is possible in a LaTeX document, |
| that your LaTeX syntax is valid and that you are using raw strings |
| if necessary to avoid unintended escape sequences. |
| |
| * :rc:`pgf.preamble` provides lots of flexibility, and lots of |
| ways to cause problems. When experiencing problems, try to minimalize or |
| disable the custom preamble. |
| |
| * Configuring an ``unicode-math`` environment can be a bit tricky. The |
| TeXLive distribution for example provides a set of math fonts which are |
| usually not installed system-wide. XeTeX, unlike LuaLatex, cannot find |
| these fonts by their name, which is why you might have to specify |
| ``\setmathfont{xits-math.otf}`` instead of ``\setmathfont{XITS Math}`` or |
| alternatively make the fonts available to your OS. See this |
| `tex.stackexchange.com question`__ for more details. |
| |
| __ https://tex.stackexchange.com/q/43642/ |
| |
| * If the font configuration used by Matplotlib differs from the font setting |
| in yout LaTeX document, the alignment of text elements in imported figures |
| may be off. Check the header of your ``.pgf`` file if you are unsure about |
| the fonts Matplotlib used for the layout. |
| |
| * Vector images and hence ``.pgf`` files can become bloated if there are a lot |
| of objects in the graph. This can be the case for image processing or very |
| big scatter graphs. In an extreme case this can cause TeX to run out of |
| memory: "TeX capacity exceeded, sorry" You can configure latex to increase |
| the amount of memory available to generate the ``.pdf`` image as discussed on |
| `tex.stackexchange.com <https://tex.stackexchange.com/q/7953/>`_. |
| Another way would be to "rasterize" parts of the graph causing problems |
| using either the ``rasterized=True`` keyword, or ``.set_rasterized(True)`` as |
| per :doc:`this example </gallery/misc/rasterization_demo>`. |
| |
| * Various math fonts are compiled and rendered only if corresponding font |
| packages are loaded. Specifically, when using ``\mathbf{}`` on Greek letters, |
| the default computer modern font may not contain them, in which case the |
| letter is not rendered. In such scenarios, the ``lmodern`` package should be |
| loaded. |
| |
| * If you still need help, please see :ref:`reporting-problems` |
| |
| .. _LaTeX: http://www.tug.org |
| .. _TeXLive: http://www.tug.org/texlive/ |
| """ |
|
|
