Add CSV file writing helper.

1 files changed, 26 insertions, 0 deletions

diff --git a/util.py b/util.py
index b092858..480ae5f 100644
--- a/util.py
+++ b/util.py
@@ -1,4 +1,5 @@
 import numpy as np
+from tempfile import NamedTemporaryFile as Tmp
 
 def load_csv_file(fname, *args, **kargs):
     f = open(fname)
@@ -7,6 +8,31 @@ def load_csv_file(fname, *args, **kargs):
     f.close() # don't leak file handles
     return data
 
+def write_csv_file(fname, rows, header=None, width=None):
+    if fname is None:
+        f = Tmp()
+    else:
+        f = open(fname, 'w')
+    if width:
+        fmt = "%%%ds" % width
+    else:
+        fmt = "%s"
+
+    if header:
+        f.write('#')
+        f.write(", ".join([fmt % str(x) for x in header]))
+        f.write('\n')
+    for row in rows:
+        f.write(' ')
+        f.write(", ".join([fmt % str(x) for x in row]))
+        f.write('\n')
+    if fname is None:
+        # keep it open
+        f.flush()
+        return f
+    else:
+        f.close()
+
 def select(keep, rows):
     ok_rows = np.zeros(len(rows), dtype=bool)
     for i, row in enumerate(rows):