Try using g4py from Chroma Geant4.
(chroma_env)delta:event blyth$ ll $VIRTUAL_ENV/src/geant4.9.5.p01/environments/g4py/
total 80
-rwxr-xr-x 1 blyth staff 15855 Mar 27 2012 configure
-rw-r--r-- 1 blyth staff 6817 Mar 27 2012 History
-rw-r--r-- 1 blyth staff 596 Mar 27 2012 GNUmakefile
-rw-r--r-- 1 blyth staff 152 Mar 27 2012 AUTHORS
-rw-r--r-- 1 blyth staff 4668 Mar 27 2012 00README
drwxr-xr-x 5 blyth staff 170 Mar 27 2012 ..
drwxr-xr-x 13 blyth staff 442 Mar 27 2012 .
drwxr-xr-x 6 blyth staff 204 Mar 27 2012 tools
drwxr-xr-x 26 blyth staff 884 Mar 27 2012 tests
drwxr-xr-x 24 blyth staff 816 Mar 27 2012 source
drwxr-xr-x 11 blyth staff 374 Mar 27 2012 site-modules
drwxr-xr-x 9 blyth staff 306 Mar 27 2012 examples
drwxr-xr-x 12 blyth staff 408 Mar 27 2012 config
Surprisingly it works, run from ipython to prevent the plot from immediately disappearing as the process exits.
chroma-
cd /usr/local/env/chroma_env/src/geant4.9.5.p01/environments/g4py/examples/emplot
(chroma_env)delta:emplot blyth$ ipython
Python 2.7.6 (default, Nov 18 2013, 15:12:51)
Type "copyright", "credits" or "license" for more information.
IPython 1.2.1 -- 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.
In [1]: run eplot.py
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Geant4 version Name: geant4-09-05-patch-01 (20-March-2012)
Copyright : Geant4 Collaboration
Reference : NIM A 506 (2003), 250-303
WWW : http://cern.ch/geant4
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