From: W. Trevor King <wking@drexel.edu>
Date: Thu, 15 Mar 2012 11:51:55 +0000 (-0400)
Subject: Fix soft jump handling for unknown `last_output`.
X-Git-Tag: 0.7~23
X-Git-Url: http://git.tremily.us/?a=commitdiff_plain;h=3e0d22c9b07c55f2d2e6f73a94c752e24ca0e10a;p=pypiezo.git

Fix soft jump handling for unknown `last_output`.

Also return after a successful soft jump.  The previous implementation
duplicated the final step.
---

diff --git a/pypiezo/base.py b/pypiezo/base.py
index 5fecd64..3e5a079 100644
--- a/pypiezo/base.py
+++ b/pypiezo/base.py
@@ -524,11 +524,20 @@ class Piezo (object):
         "Move the output named `axis_name` to `position`."
         _LOG.debug('jump %s to %s in %d steps' % (axis_name, position, steps))
         if steps > 1:
-            orig_pos = self.last_output[axis_name]
-            for pos in _numpy.linspace(orig_pos, position, steps+1)[1:]:
-                self.jump(axis_name=axis_name, position=pos)
-                if sleep:
-                    _sleep(sleep)
+            try:
+                orig_pos = self.last_output[axis_name]
+            except KeyError, e:
+                _LOG.warn(
+                    ("cannot make a soft jump to {} because we don't have a "
+                     'last-output position for {}').format(
+                        position, axis_name))
+                steps = 1
+            else:
+                for pos in _numpy.linspace(orig_pos, position, steps+1)[1:]:
+                    self.jump(axis_name=axis_name, position=pos)
+                    if sleep:
+                        _sleep(sleep)
+                return
         position = int(position)
         channel = self.channel_by_name(name=axis_name)
         channel.data_write(position)