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diff --git a/gr-fec/python/fec/LDPC/Generate_LDPC_matrix.py b/gr-fec/python/fec/LDPC/Generate_LDPC_matrix.py
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+#!/usr/bin/env python
+#
+# Copyright 2015 Free Software Foundation, Inc.
+#
+# This file is part of GNU Radio
+#
+# GNU Radio 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, or (at your option)
+# any later version.
+#
+# GNU Radio 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 GNU Radio; see the file COPYING.  If not, write to
+# the Free Software Foundation, Inc., 51 Franklin Street,
+# Boston, MA 02110-1301, USA.
+#
+
+from Generate_LDPC_matrix_functions import *
+
+# This is an example of how to generate a parity check matrix for
+# use with the LDPC Richardson Urbanke encoder. A significant amount
+# of matrix manipulation is required, so this process should be done
+# before using the encoder at run-time. This process can take quite
+# a while, with more time required for larger matrices.
+
+# Not all attempts to create a parity check matrix will be
+# successful. The script will terminate and output error messages
+# when the process fails. To increase verbosity, edit the verbose
+# variable at the top of Generate_LDPC_matrix_functions.py.
+
+# Because random number generation and
+# shuffling methods are used, it is not possible to predict what
+# starting conditions will result in success. It requires a bit of
+# trial and error.
+
+# ----------------------------------------------------------------- #
+
+# First, generate a regular LDPC parity check matrix. Specify
+# the properties desired. For example:
+n = 200   # number of columns, corresponds to codeword length
+p = 3     # column weight
+q = 5     # row weight
+
+parity_check_matrix = LDPC_matrix(n_p_q = [n,p,q])
+
+# Richardson and Urbanke's preprocessing method requires a full rank
+# matrix to start. The matrices generated by the
+# regular_LDPC_code_contructor function will never be full rank. So,
+# use the get_full_rank_H_matrix function.
+newH = get_full_rank_H_matrix(parity_check_matrix.H)
+
+# At this point, the matrix is no longer regular. (The row/column
+# weights are not the same for all rows/columns.)
+
+# Next, some preprocessing steps need to be performed as described
+# Richardson and Urbanke in Modern Coding Theory, Appendix A. This
+# can take a while...
+[bestH,g] = get_best_matrix(newH,100)
+
+# Print out some of the resulting properties.
+n = bestH.shape[1]
+k = n - bestH.shape[0]
+print "Parity check matrix properties:"
+print "\tSize :", bestH.shape
+print "\tRank :", linalg.matrix_rank(bestH)
+print "\tRate : %.3f" % ((k*1.0)/n)
+print "\tn    :", n, " (codeword length)"
+print "\tk    :", k, " (info word length)"
+print "\tgap  : %i" % g
+
+# Save the matrix to an alist file for future use:
+alist_filename = "n_%04i_k_%04i_gap_%02i.alist" % (n,k,g)
+parity_check_matrix.write_alist_file(alist_filename,bestH)
+print '\nMatrix saved to alist file:', alist_filename, "\n"