<html><head><meta http-equiv="Content-Type" content="text/html charset=utf-8"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class="">Hi,<div class="">I have a tRNA molecule and I would like to measure the angles between two nitrogenous bases. I created two planes, each for each base. When I select both planes, in order to measure the angles between them (Structure Measurements Axes/Planes/Centroids) I get following message:</div><div class=""><br class=""></div><div class=""><br class=""></div><div class=""><div class=""><i class=""><type 'exceptions.UnboundLocalError'> Exception in Tk callback</i></div><div class=""><i class=""> Function: <bound method SortableTable._browseCmd of <CGLtk.Table.SortableTable instance at 0x117990638>> (type: <type 'instancemethod'>)</i></div><div class=""><i class=""> Args: ('1',)</i></div><div class=""><i class="">Traceback (innermost last):</i></div><div class=""><i class=""> File "/Applications/Chimera.app/Contents/Resources/lib/python2.7/site-packages/Pmw/Pmw_1_3/lib/PmwBase.py", line 1747, in __call__</i></div><div class=""><i class=""> return apply(self.func, args)</i></div><div class=""><i class=""> File "/Applications/Chimera.app/Contents/Resources/share/CGLtk/Table.py", line 1043, in _browseCmd</i></div><div class=""><i class=""> self.userBrowseCmd(self.selected())</i></div><div class=""><i class=""> File "/Applications/Chimera.app/Contents/Resources/share/StructMeasure/Geometry.py", line 268, in _tableCB</i></div><div class=""><i class=""> self.feedback(sels)</i></div><div class=""><i class=""> File "/Applications/Chimera.app/Contents/Resources/share/StructMeasure/Geometry.py", line 113, in feedback</i></div><div class=""><i class=""> diff = " ".join(words2[i:])</i></div><div class=""><i class=""><type 'exceptions.UnboundLocalError'>: local variable 'i' referenced before assignment</i></div><div class=""><i class=""><br class=""></i></div><div class=""><i class="">UnboundLocalError: local variable 'i' referenced before assignment</i></div><div class=""><i class=""><br class=""></i></div><div class=""><i class=""> File "/Applications/Chimera.app/Contents/Resources/share/StructMeasure/Geometry.py", line 113, in feedback</i></div><div class=""><i class=""> diff = " ".join(words2[i:])</i></div><div class=""><i class=""><br class=""></i></div><div class=""><i class="">See reply log for Python traceback.</i></div></div><div class=""><br class=""></div><div class=""><br class=""></div><div class=""><br class=""></div><div class="">I really don’t know how can I solve this problem.. I’d be really grateful if you could help me or give me some hints!</div><div class="">thank you a lot</div><div class=""><br class=""></div><div class="">Letizia</div></body></html>