[Yt-svn] yt-commit r1688 - trunk/yt/lagos

[mturk at wrangler.dreamhost.com]

Author: mturk
Date: Fri Apr  9 16:07:22 2010
New Revision: 1688
URL: http://yt.enzotools.org/changeset/1688

Log:
Supporting possibility for no field values to be above zero, and also adding an
editorial comment.



Modified:
   trunk/yt/lagos/DerivedQuantities.py

Modified: trunk/yt/lagos/DerivedQuantities.py
==============================================================================
--- trunk/yt/lagos/DerivedQuantities.py	(original)
+++ trunk/yt/lagos/DerivedQuantities.py	Fri Apr  9 16:07:22 2010
@@ -380,6 +380,8 @@
     :param fields: A field name, or a list of field names
     :param filter: a string to be evaled to serve as a data filter.
     """
+    # There is a heck of a lot of logic in this.  I really wish it were more
+    # elegant.
     fields = ensure_list(fields)
     if filter is not None: this_filter = eval(filter)
     mins, maxs = [], []
@@ -389,9 +391,14 @@
             maxs.append(-1e90)
             continue
         if filter is None:
-            # Note that we're hijacking an argument here
-            if non_zero: nz_filter = data[field]>0.0
-            else: nz_filter = None
+            if non_zero:
+                nz_filter = data[field]>0.0
+                if not nz_filter.any():
+                    mins.append(1e90)
+                    maxs.append(-1e90)
+                    continue
+            else:
+                nz_filter = None
             mins.append(data[field][nz_filter].min())
             maxs.append(data[field][nz_filter].max())
         else: