Add error handling for invalid position data arrays when drawing. Fixes #74.
Add error handling for invalid position data arrays when drawing.
Fixes #74.

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extra : convert_revision : svn%3A3ed01bd8-26fb-0310-9e4c-ca1a4053419f/networkx/trunk%40460

nathania/networkx,blublud/networkx,yashu-seth/networkx,jakevdp/networkx,farhaanbukhsh/networkx,kernc/networkx,wasade/networkx,ghdk/networkx,dhimmel/networkx,tmilicic/networkx,kernc/networkx,nathania/networkx,jtorrents/networkx,andnovar/networkx,RMKD/networkx,farhaanbukhsh/networkx,ionanrozenfeld/networkx,debsankha/networkx,sharifulgeo/networkx,dmoliveira/networkx,jfinkels/networkx,harlowja/networkx,bzero/networkx,harlowja/networkx,nathania/networkx,kai5263499/networkx,michaelpacer/networkx,bzero/networkx,debsankha/networkx,jni/networkx,ghdk/networkx,dhimmel/networkx,jtorrents/networkx,ionanrozenfeld/networkx,jni/networkx,RMKD/networkx,beni55/networkx,jakevdp/networkx,jni/networkx,dmoliveira/networkx,blublud/networkx,chrisnatali/networkx,RMKD/networkx,dmoliveira/networkx,jakevdp/networkx,chrisnatali/networkx,harlowja/networkx,OrkoHunter/networkx,aureooms/networkx,ionanrozenfeld/networkx,sharifulgeo/networkx,jcurbelo/networkx,aureooms/networkx,farhaanbukhsh/networkx,cmtm/networkx,JamesClough/networkx,Sixshaman/networkx,dhimmel/networkx,blublud/networkx,aureooms/networkx,kernc/networkx,debsankha/networkx,bzero/networkx,SanketDG/networkx,ltiao/networkx,goulu/networkx,kai5263499/networkx,NvanAdrichem/networkx,kai5263499/networkx,sharifulgeo/networkx,ghdk/networkx,chrisnatali/networkx