Fix swapped docstrings for CurvePlugin's DifferenceCommand and DerivativeCommand

diff --git a/hooke/plugin/curve.py b/hooke/plugin/curve.py
index b517c0b73f23c9290196734b50ff5b5bddbf9aab..7621fc79d2b2a899a7ac4f91e070722e79bcccfb 100644 (file)
--- a/hooke/plugin/curve.py
+++ b/hooke/plugin/curve.py
@@ -172,11 +172,7 @@ True if you want the column-naming header line.
         f.close()
 
 class DifferenceCommand (Command):
-    """Calculate the derivative (actually, the discrete differentiation)
-    of a curve data block.
-
-    See :func:`hooke.util.calculus.derivative` for implementation
-    details.
+    """Calculate the difference between two blocks of data.
     """
     def __init__(self, plugin):
         super(DifferenceCommand, self).__init__(
@@ -213,7 +209,11 @@ Column of data block to differentiate.
         outqueue.put(out)
 
 class DerivativeCommand (Command):
-    """Calculate the difference between two blocks of data.
+    """Calculate the derivative (actually, the discrete differentiation)
+    of a curve data block.
+
+    See :func:`hooke.util.calculus.derivative` for implementation
+    details.
     """
     def __init__(self, plugin):
         super(DerivativeCommand, self).__init__(