# HG changeset patch
# User Jeff Hammel <k0scist@gmail.com>
# Date 1421700685 28800
# Node ID e7e49b46832b8ca62704d40fc0f4be105f7e21a3
# Parent  e39643d18d828fd77bd5e78bc54092c60fcfcfbd
make this function semi-meaningful

diff -r e39643d18d82 -r e7e49b46832b numerics/data.py
--- a/numerics/data.py	Mon Jan 19 12:45:06 2015 -0800
+++ b/numerics/data.py	Mon Jan 19 12:51:25 2015 -0800
@@ -6,7 +6,11 @@
 
 from collections import OrderedDict
 
-__all__ = ['ColumnNumberException', 'ColumnLengthException', 'Rows', 'Columns']
+__all__ = ['ColumnNumberException',
+           'ColumnLengthException',
+           'transpose',
+           'Rows',
+           'Columns']
 
 
 class ColumnNumberException(Exception):
@@ -25,10 +29,12 @@
     if not array:
         return array  # nothing to do
 
-    n_cols = len(array[0])
-    retval = [[]] * n_cols
+    n_cols = set([len(row) for row in array])
+    if len(n_cols) != 1:
+        raise Exception("Differing number of columns found: {}".format(', '.join(sorted(n_cols))))
+
     return zip(*array)
-    # XXX this is a nothing function; we shouldn't use this
+
 
 class ColumnLengthException(ColumnNumberException):
     """