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{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"Pip install can't find freetype and png despite them being installed","articleBody":"I have a virtual environment on a new device for Python2.7. I want to install matplotlib, but it is throwing me the following error:\r\n\r\n```\r\n(venv2.7) osm:~$ pip install matplotlib \r\nDEPRECATION: Python 2.7 will reach the end of its life on January 1st, 2020. Please upgrade your Python as Python 2.7 won't be maintained after that date. A future version of pip will drop support for Python 2.7. More details about Python 2 support in pip, can be found at https://pip.pypa.io/en/latest/development/release-process/#python-2-support\r\nCollecting matplotlib\r\n  Using cached https://files.pythonhosted.org/packages/1e/20/2032ad99f0dfe0f60970941af36e8d0942d3713f442bb3df37ac35d67358/matplotlib-2.2.4.tar.gz\r\n    ERROR: Command errored out with exit status 1:\r\n     command: /home/osm/venv2.7/bin/python2.7 -c 'import sys, setuptools, tokenize; sys.argv[0] = '\"'\"'/tmp/pip-install-v0wvdH/matplotlib/setup.py'\"'\"'; __file__='\"'\"'/tmp/pip-install-v0wvdH/matplotlib/setup.py'\"'\"';f=getattr(tokenize, '\"'\"'open'\"'\"', open)(__file__);code=f.read().replace('\"'\"'\\r\\n'\"'\"', '\"'\"'\\n'\"'\"');f.close();exec(compile(code, __file__, '\"'\"'exec'\"'\"'))' egg_info --egg-base pip-egg-info\r\n         cwd: /tmp/pip-install-v0wvdH/matplotlib/\r\n    Complete output (62 lines):\r\n    ============================================================================\r\n    Edit setup.cfg to change the build options\r\n    \r\n    BUILDING MATPLOTLIB\r\n                matplotlib: yes [2.2.4]\r\n                    python: yes [2.7.15+ (default, Nov 27 2018, 23:36:35)  [GCC\r\n                            7.3.0]]\r\n                  platform: yes [linux2]\r\n    \r\n    REQUIRED DEPENDENCIES AND EXTENSIONS\r\n                     numpy: yes [version 1.16.5]\r\n          install_requires: yes [handled by setuptools]\r\n                    libagg: yes [pkg-config information for 'libagg' could not\r\n                            be found. Using local copy.]\r\n-----\u003e            freetype: no  [The C/C++ header for freetype2 (ft2build.h)\r\n                            could not be found.  You may need to install the\r\n                            development package.]\r\n-----\u003e                 png: no  [The C/C++ header for libpng (png.h) could not\r\n                            be found.  You may need to install the development\r\n                            package.]\r\n                     qhull: yes [pkg-config information for 'libqhull' could not\r\n                            be found. Using local copy.]\r\n    \r\n    OPTIONAL SUBPACKAGES\r\n               sample_data: yes [installing]\r\n                  toolkits: yes [installing]\r\n                     tests: no  [skipping due to configuration]\r\n            toolkits_tests: no  [skipping due to configuration]\r\n    \r\n    OPTIONAL BACKEND EXTENSIONS\r\n                    macosx: no  [Mac OS-X only]\r\n                    qt5agg: no  [PySide2 not found; PyQt5 not found]\r\n                    qt4agg: no  [PySide not found; PyQt4 not found]\r\n                   gtk3agg: no  [Requires pygobject to be installed.]\r\n                 gtk3cairo: no  [Requires cairocffi or pycairo to be installed.]\r\n                    gtkagg: no  [Requires pygtk]\r\n                     tkagg: yes [installing; run-time loading from Python Tcl /\r\n                            Tk]\r\n                     wxagg: no  [requires wxPython]\r\n                       gtk: no  [Requires pygtk]\r\n                       agg: yes [installing]\r\n                     cairo: no  [cairocffi or pycairo not found]\r\n                 windowing: no  [Microsoft Windows only]\r\n    \r\n    OPTIONAL LATEX DEPENDENCIES\r\n                    dvipng: no\r\n               ghostscript: yes [version 9.26]\r\n                     latex: no\r\n                   pdftops: yes [version 0.62.0]\r\n    \r\n    OPTIONAL PACKAGE DATA\r\n                      dlls: no  [skipping due to configuration]\r\n    \r\n    ============================================================================\r\n                            * The following required packages can not be built:\r\n                            * freetype, png\r\n                            * Try installing freetype with `apt-get install\r\n                            * libfreetype6-dev` and pkg-config with `apt-get\r\n                            * install pkg-config`\r\n                            * Try installing png with `apt-get install\r\n                            * libpng12-dev` and pkg-config with `apt-get install\r\n                            * pkg-config`\r\n    ----------------------------------------\r\nERROR: Command errored out with exit status 1: python setup.py egg_info Check the logs for full command output.\r\n```\r\n\r\nHowever, considering the `png.h` file, I know that the header file is in my path, as \r\n\r\n```\r\n(venv2.7) osm:~$ echo $CPATH\r\n/home/osm/.local/include:\r\n(venv2.7) osm:~$ echo $C_INCLUDE_PATH\r\n/home/osm/.local/include:\r\n```\r\nand\r\n```\r\n(venv2.7) osm:~$ tree /home/osm/.local/include/ -L 1\r\n/home/osm/.local/include/\r\n├── freetype2\r\n├── gsl\r\n├── libpng16\r\n├── ncurses\r\n├── pngconf.h -\u003e libpng16/pngconf.h\r\n├── png.h -\u003e libpng16/png.h\r\n└── pnglibconf.h -\u003e libpng16/pnglibconf.h\r\n```\r\n\r\nI have just done local installs from source for both freetype and png and so I have no idea why it can't find the headers for these. \r\n\r\n\u003e I know this problem is similar to \r\n\u003e https://github.com/matplotlib/matplotlib/issues/12169/","author":{"url":"https://github.com/oliversheridanmethven","@type":"Person","name":"oliversheridanmethven"},"datePublished":"2019-08-29T13:35:04.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":6},"url":"https://github.com/15155/matplotlib/issues/15155"}