I installed matplotlib, anaconda, ipython on OS X El Captain. However even after trying to set up the environment variables in all possible ways, I am unable to start up the ipython shell --pylab version.
Here is the error.
ImportError: dlopen(/Users/apple/anaconda/lib/python2.7/site-packages/matplotlib/_png.so, 2): Library not loaded: @rpath/libpng16.16.dylib
Referenced from: /Users/apple/anaconda/lib/python2.7/site-packages/matplotlib/_png.so
Reason: Incompatible library version: _png.so requires version 40.0.0 or later, but libpng16.16.dylib provides version 39.0.0
Initially, matplotlib wasn't showing up after a normal pip install matplotlib. After reinstalling matplotlib from 'conda' using conda install -c conda-forge matplotlib=1.5.2, I am not getting a import error pf package not found but the pylab version is still not functional. I tried upgrading libpng library, and installed it in /usr/local but then also no use. I don't know how _png.so is to be upgraded in the /anaconda/site-packages/matplotlib folder. I have also tried setting up the environment variables of the libpng.x.dylib library I don't know why its not working or may be I have not done it correctly.
Here is the full screenshot just in case its necessary:-
IPython 5.0.0 -- An enhanced Interactive Python.
? -> Introduction and overview of IPython's features.
%quickref -> Quick reference.
help -> Python's own help system.
object? -> Details about 'object', use 'object??' for extra details.
TerminalIPythonApp WARNING | Eventloop or matplotlib integration failed. Is matplotlib installed?
ImportError Traceback (most recent call last)
/Users/apple/anaconda/lib/python2.7/site-packages/IPython/core/shellapp.pyc in <lambda>(key)
196 shell = self.shell
197 if self.pylab:
--> 198 enable = lambda key: shell.enable_pylab(key, import_all=self.pylab_import_all)
199 key = self.pylab
200 elif self.matplotlib:
/Users/apple/anaconda/lib/python2.7/site-packages/IPython/core/interactiveshell.pyc in enable_pylab(self, gui, import_all, welcome_message)
2972 from IPython.core.pylabtools import import_pylab
2973
---> 2974 gui, backend = self.enable_matplotlib(gui)
2975
2976 # We want to prevent the loading of pylab to pollute the user's
/Users/apple/anaconda/lib/python2.7/site-packages/IPython/core/interactiveshell.pyc in enable_matplotlib(self, gui)
2933 gui, backend = pt.find_gui_and_backend(self.pylab_gui_select)
2934
--->2935 pt.activate_matplotlib(backend)
2936 pt.configure_inline_support(self, backend)
2937
/Users/apple/anaconda/lib/python2.7/site-packages/IPython/core/pylabtools.pyc in activate_matplotlib(backend)
293 matplotlib.rcParams['backend'] = backend
294
--> 295 import matplotlib.pyplot
296 matplotlib.pyplot.switch_backend(backend)
297
/Users/apple/anaconda/lib/python2.7/site-packages/matplotlib/pyplot.py in <module>()
27 from cycler import cycler
28 import matplotlib
--->29 import matplotlib.colorbar
30 from matplotlib import style
31 from matplotlib import _pylab_helpers, interactive
/Users/apple/anaconda/lib/python2.7/site-packages/matplotlib/colorbar.py in <module>()
32 import matplotlib.artist as martist
33 import matplotlib.cbook as cbook
---> 34 import matplotlib.collections as collections
35 import matplotlib.colors as colors
36 import matplotlib.contour as contour
/Users/apple/anaconda/lib/python2.7/site-packages/matplotlib/collections.py in <module>()
25 import matplotlib.artist as artist
26 from matplotlib.artist import allow_rasterization
---> 27 import matplotlib.backend_bases as backend_bases
28 import matplotlib.path as mpath
29 from matplotlib import _path
/Users/apple/anaconda/lib/python2.7/site-packages/matplotlib/backend_bases.py in <module>()
60
61 import matplotlib.tight_bbox as tight_bbox
---> 62 import matplotlib.textpath as textpath
63 from matplotlib.path import Path
64 from matplotlib.cbook import mplDeprecation, warn_deprecated
/Users/apple/anaconda/lib/python2.7/site-packages/matplotlib/textpath.py in <module>()
16 from matplotlib.ft2font import FT2Font, KERNING_DEFAULT, LOAD_NO_HINTING
17 from matplotlib.ft2font import LOAD_TARGET_LIGHT
---> 18 from matplotlib.mathtext import MathTextParser
19 import matplotlib.dviread as dviread
20 from matplotlib.font_manager import FontProperties
/Users/apple/anaconda/lib/python2.7/site-packages/matplotlib/mathtext.py in <module>()
58
59 import matplotlib.colors as mcolors
---> 60 import matplotlib._png as _png
61 ####################
62
ImportError: dlopen(/Users/apple/anaconda/lib/python2.7/site-packages/matplotlib/_png.so, 2): Library not loaded: @rpath/libpng16.16.dylib
Referenced from: /Users/apple/anaconda/lib/python2.7/site-packages/matplotlib/_png.so
Reason: Incompatible library version: _png.so requires version 40.0.0 or later, but libpng16.16.dylib provides version 39.0.0