fix for string sub
fix for string sub
sjsrey/pysal_core,pedrovma/pysal,sjsrey/pysal_core,jlaura/pysal,pysal/pysal,ljwolf/pysal_core,schmidtc/pysal,lixun910/pysal,ljwolf/pysal,ljwolf/pysal_core,pastephens/pysal,lixun910/pysal,spreg-git/pysal,nathania/pysal,weikang9009/pysal,TaylorOshan/pysal,darribas/pysal,lanselin/pysal,chhao91/pysal,badjr/pysal,TaylorOshan/pysal,ljwolf/pysal_core,TaylorOshan/pysal,ljwolf/pysal,lixun910/pysal,darribas/pysal,dfolch/pysal,nathania/pysal,badjr/pysal,chhao91/pysal,sjsrey/pysal,pastephens/pysal,pastephens/pysal,sjsrey/pysal_core,hasecbinusr/pysal,ljwolf/pysal,schmidtc/pysal,hasecbinusr/pysal,jlaura/pysal,jlaura/pysal,spreg-git/pysal,dfolch/pysal,hasecbinusr/pysal