# HG changeset patch
# User Jeff Hammel <k0scist@gmail.com>
# Date 1415141650 28800
# Node ID 75270e7a051b48d10bf980e23e1c9d68a3213b39
# Parent  c2c92c8da61132cba7333e6068046b4b9c05dc86
add ability to add an index and fix a few bugs

diff -r c2c92c8da611 -r 75270e7a051b numerics/read.py
--- a/numerics/read.py	Thu Oct 09 15:01:01 2014 -0700
+++ b/numerics/read.py	Tue Nov 04 14:54:10 2014 -0800
@@ -99,6 +99,9 @@
         self.add_argument('-o', '--output', dest='output',
                           type=argparse.FileType('a'), default=sys.stdout,
                           help='output destination, or stdout')
+        self.add_argument('--index', dest='index',
+                          action='store_true', default=False,
+                          help="prepend each row with numeric index")
         self.options = None
 
     def parse_args(self, *args, **kw):
@@ -126,8 +129,14 @@
             row.extend(options.added_columns)
 
     if options.columns:
-        rows = [[row[column] for column in options[columns]]
-                for row in rows]
+        # filter by column
+        data = [[row[column] for column in options.columns]
+                for row in data]
+
+    if options.index:
+        # prepend numeric index
+        for index, row in enumerate(data):
+            row.insert(0, index)
 
     # write CSV
     writer = csv.writer(options.output)