demos_core added.

demos/demos_core.py

+## NIFTY (Numerical Information Field Theory) has been developed at the
+## Max-Planck-Institute for Astrophysics.
+##
+## Copyright (C) 2014 Max-Planck-Society
+##
+## Author: Marco Selig
+## Project homepage: <http://www.mpa-garching.mpg.de/ift/nifty/>
+##
+## This program is free software: you can redistribute it and/or modify
+## it under the terms of the GNU General Public License as published by
+## the Free Software Foundation, either version 3 of the License, or
+## (at your option) any later version.
+##
+## This program is distributed in the hope that it will be useful,
+## but WITHOUT ANY WARRANTY; without even the implied warranty of
+## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+## See the GNU General Public License for more details.
+##
+## You should have received a copy of the GNU General Public License
+## along with this program. If not, see <http://www.gnu.org/licenses/>.
+
+"""
+    NIFTY provides a number of demonstrations that you can run either using
+    ``execfile`` provided with (absolute or relative) file names or using
+    ``run -m`` providing the module name. You can retrieve the directory of
+    the NIFTY demos calling :py:func:`get_demo_dir`.
+
+"""
+import os
+import nifty as nt
+
+def get_demo_dir():
+    """
+        Returns the path of the NIFTY demos directory.
+
+    """
+    return os.path.split(nt.demos.__file__)[0]
+