--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/numerics/smooth.py	Thu Oct 09 15:01:01 2014 -0700
@@ -0,0 +1,70 @@
+#!/usr/bin/env python
+# -*- coding: utf-8 -*-
+
+"""
+smoothing
+"""
+
+# imports
+import argparse
+import os
+import subprocess
+import sys
+
+# module globals
+__all__ = ['main', 'smooth', 'SmoothingParser']
+
+def smooth(iterations, *values):
+    assert len(values) >= 2
+    while iterations > 0:
+        inner = [sum(i) for i in zip(values[1:], values[:-1])]
+        left = [inner[0]] + inner[:]
+        right = inner[:] + [inner[-1]]
+        values = [0.25*sum(i) for i in zip(left, right)]
+        iterations -= 1
+    return values
+
+class SmoothingParser(argparse.ArgumentParser):
+    """`smooth` CLI option parser"""
+    def __init__(self, **kwargs):
+        kwargs.setdefault('description', __doc__)
+        argparse.ArgumentParser.__init__(self, **kwargs)
+        self.add_argument('input', nargs='?',
+                          type=argparse.FileType('r'), default=sys.stdin,
+                          help='input file, or read from stdin if ommitted')
+        self.add_argument('-o', '--output', dest='output',
+                          type=argparse.FileType('a'), default=sys.stdout,
+                          help="output file to write to, or stdout")
+        self.add_argument('-n', '--iterations', dest='iterations',
+                          type=int, default=1,
+                          help="number of iterations to apply [DEFAULT: %(default)s]")
+        self.options = None
+
+    def parse_args(self, *args, **kw):
+        options = argparse.ArgumentParser.parse_args(self, *args, **kw)
+        self.validate(options)
+        self.options = options
+        return options
+
+    def validate(self, options):
+        """validate options"""
+
+def main(args=sys.argv[1:]):
+    """CLI"""
+
+    # parse command line options
+    parser = SmoothingParser()
+    options = parser.parse_args(args)
+
+    # read data
+    data = options.input.read().strip().split()
+    data = [float(i) for i in data]
+
+    smoothed = smooth(options.iterations, *data)
+
+    # write data
+    options.output.write('\n'.join([str(i) for i in smoothed]))
+
+if __name__ == '__main__':
+    main()
+