ENH: make sure that number of rows is not < 0
ENH: make sure that number of rows is not < 0

cjh1/VTK,jeffbaumes/jeffbaumes-vtk,aashish24/VTK-old,berendkleinhaneveld/VTK,demarle/VTK,gram526/VTK,collects/VTK,gram526/VTK,mspark93/VTK,mspark93/VTK,Wuteyan/VTK,spthaolt/VTK,sumedhasingla/VTK,SimVascular/VTK,arnaudgelas/VTK,spthaolt/VTK,jeffbaumes/jeffbaumes-vtk,SimVascular/VTK,johnkit/vtk-dev,jmerkow/VTK,ashray/VTK-EVM,candy7393/VTK,aashish24/VTK-old,sankhesh/VTK,keithroe/vtkoptix,sumedhasingla/VTK,biddisco/VTK,daviddoria/PointGraphsPhase1,cjh1/VTK,spthaolt/VTK,spthaolt/VTK,demarle/VTK,Wuteyan/VTK,jmerkow/VTK,biddisco/VTK,johnkit/vtk-dev,arnaudgelas/VTK,jeffbaumes/jeffbaumes-vtk,keithroe/vtkoptix,SimVascular/VTK,naucoin/VTKSlicerWidgets,aashish24/VTK-old,demarle/VTK,SimVascular/VTK,biddisco/VTK,gram526/VTK,jmerkow/VTK,collects/VTK,jmerkow/VTK,mspark93/VTK,SimVascular/VTK,ashray/VTK-EVM,keithroe/vtkoptix,sumedhasingla/VTK,SimVascular/VTK,jeffbaumes/jeffbaumes-vtk,cjh1/VTK,Wuteyan/VTK,candy7393/VTK,cjh1/VTK,jmerkow/VTK,msmolens/VTK,SimVascular/VTK,johnkit/vtk-dev,hendradarwin/VTK,berendkleinhaneveld/VTK,msmolens/VTK,naucoin/VTKSlicerWidgets,berendkleinhaneveld/VTK,msmolens/VTK,candy7393/VTK,candy7393/VTK,naucoin/VTKSlicerWidgets,berendkleinhaneveld/VTK,daviddoria/PointGraphsPhase1,hendradarwin/VTK,biddisco/VTK,mspark93/VTK,johnkit/vtk-dev,berendkleinhaneveld/VTK,aashish24/VTK-old,demarle/VTK,biddisco/VTK,hendradarwin/VTK,sankhesh/VTK,candy7393/VTK,msmolens/VTK,jmerkow/VTK,Wuteyan/VTK,spthaolt/VTK,biddisco/VTK,collects/VTK,sumedhasingla/VTK,naucoin/VTKSlicerWidgets,sankhesh/VTK,arnaudgelas/VTK,demarle/VTK,spthaolt/VTK,hendradarwin/VTK,gram526/VTK,cjh1/VTK,ashray/VTK-EVM,sankhesh/VTK,candy7393/VTK,sumedhasingla/VTK,naucoin/VTKSlicerWidgets,aashish24/VTK-old,mspark93/VTK,demarle/VTK,daviddoria/PointGraphsPhase1,jmerkow/VTK,msmolens/VTK,daviddoria/PointGraphsPhase1,mspark93/VTK,johnkit/vtk-dev,SimVascular/VTK,sumedhasingla/VTK,gram526/VTK,daviddoria/PointGraphsPhase1,candy7393/VTK,mspark93/VTK,ashray/VTK-EVM,johnkit/vtk-dev,aashish24/VTK-old,berendkleinhaneveld/VTK,ashray/VTK-EVM,johnkit/vtk-dev,collects/VTK,keithroe/vtkoptix,demarle/VTK,arnaudgelas/VTK,msmolens/VTK,arnaudgelas/VTK,daviddoria/PointGraphsPhase1,ashray/VTK-EVM,msmolens/VTK,arnaudgelas/VTK,Wuteyan/VTK,gram526/VTK,keithroe/vtkoptix,hendradarwin/VTK,hendradarwin/VTK,berendkleinhaneveld/VTK,gram526/VTK,collects/VTK,gram526/VTK,hendradarwin/VTK,keithroe/vtkoptix,mspark93/VTK,Wuteyan/VTK,sankhesh/VTK,spthaolt/VTK,collects/VTK,msmolens/VTK,sankhesh/VTK,Wuteyan/VTK,naucoin/VTKSlicerWidgets,jmerkow/VTK,demarle/VTK,keithroe/vtkoptix,sankhesh/VTK,candy7393/VTK,cjh1/VTK,ashray/VTK-EVM,jeffbaumes/jeffbaumes-vtk,biddisco/VTK,sumedhasingla/VTK,ashray/VTK-EVM,sankhesh/VTK,jeffbaumes/jeffbaumes-vtk,sumedhasingla/VTK,keithroe/vtkoptix