[Commit-gnuradio] r4370 - gnuradio/branches/developers/jcorgan/digital/gnuradio-examples/python/digital

[jcorgan]

Author: jcorgan
Date: 2007-02-04 13:12:37 -0700 (Sun, 04 Feb 2007)
New Revision: 4370

Added:
   
gnuradio/branches/developers/jcorgan/digital/gnuradio-examples/python/digital/run_length.py
Modified:
   
gnuradio/branches/developers/jcorgan/digital/gnuradio-examples/python/digital/README
Log:
Added utility to determine maximum bit run length in a file.


Modified: 
gnuradio/branches/developers/jcorgan/digital/gnuradio-examples/python/digital/README
===================================================================
--- 
gnuradio/branches/developers/jcorgan/digital/gnuradio-examples/python/digital/README
        2007-02-04 19:59:02 UTC (rev 4369)
+++ 
gnuradio/branches/developers/jcorgan/digital/gnuradio-examples/python/digital/README
        2007-02-04 20:12:37 UTC (rev 4370)
@@ -75,3 +75,10 @@
 
 This now uses a carrier sense MAC, so you should be able to ssh
 between the machines, web browse, etc.
+
+* run_length.py: This program takes a single argument '-f FILE' and
+outputs the number of runs of similar bits within the file. It is
+useful as a diagnostic tool when experimenting with line coding or
+whitening algorithms.
+
+

Added: 
gnuradio/branches/developers/jcorgan/digital/gnuradio-examples/python/digital/run_length.py
===================================================================
--- 
gnuradio/branches/developers/jcorgan/digital/gnuradio-examples/python/digital/run_length.py
                         (rev 0)
+++ 
gnuradio/branches/developers/jcorgan/digital/gnuradio-examples/python/digital/run_length.py
 2007-02-04 20:12:37 UTC (rev 4370)
@@ -0,0 +1,83 @@
+#!/usr/bin/env python
+#
+# Copyright 2007 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 2, 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 optparse import OptionParser
+import sys
+
+def main():
+    parser = OptionParser()
+    parser.add_option("-f", "--file", default=None,
+                      help="Choose file to read data from.")
+    (options, args) = parser.parse_args()
+
+    if options.file == None:
+        print "Must specify file to read from using '-f'."
+        sys.exit(1)
+    print "Using", options.file, "for data."
+
+    f = open(options.file, 'r')
+    runs = []
+    count = 0
+    current = 0
+    bytes = 0
+    bits = 0
+    
+    for ch in f.read():
+        x = ord(ch)
+        bytes = bytes + 1
+        for i in range(7,-1,-1):
+            bits = bits + 1
+            t = (x >> i) & 0x1
+            if t == current:
+                count = count + 1
+            else:
+                if count > 0:
+                    if len(runs) < count:
+                        for j in range(count - len(runs)):
+                            runs.append(0);
+                    runs[count-1] = runs[count-1] + 1
+
+                current = 1-current;
+                count = 1
+
+    # Deal with last run at EOF
+    if len(runs) < count and count > 0:
+        for j in range(count - len(runs)):
+            runs.append(0);
+    runs[count-1] = runs[count-1] + 1
+
+    chk = 0
+    print "Bytes read: ", bytes
+    print "Bits read:  ", bits
+    print
+    for i in range(len(runs)):
+        chk = chk + runs[i]*(i+1)
+        print "Runs of length", i+1, ":", runs[i]
+    print
+    print "Sum of runs:", chk, "bits"
+    print
+    print "Maximum run length is", len(runs), "bits"
+
+if __name__ == "__main__":
+    main()
+
+    


Property changes on: 
gnuradio/branches/developers/jcorgan/digital/gnuradio-examples/python/digital/run_length.py
___________________________________________________________________
Name: svn:executable
   + *