From 1c2e953f173223129a710459e79c2d61ad61ddb1 Mon Sep 17 00:00:00 2001 From: Maximilian Albert Date: Sun, 6 Nov 2016 17:52:17 +0000 Subject: [PATCH] DOC: Tweak error message to make it slightly more readable / easier to parse. --- pandas/tools/merge.py | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/pandas/tools/merge.py b/pandas/tools/merge.py index 86e2e8aabbee1..d2060185c3246 100644 --- a/pandas/tools/merge.py +++ b/pandas/tools/merge.py @@ -816,8 +816,8 @@ def _validate_specification(self): self.left_on = self.right_on = common_cols elif self.on is not None: if self.left_on is not None or self.right_on is not None: - raise MergeError('Can only pass on OR left_on and ' - 'right_on') + raise MergeError('Can only pass argument "on" OR "left_on" ' + 'and "right_on", not a combination of both.') self.left_on = self.right_on = self.on elif self.left_on is not None: n = len(self.left_on)