TST: improve coverage of nd_grid
TST: improve coverage of nd_grid

grlee77/numpy,madphysicist/numpy,seberg/numpy,WarrenWeckesser/numpy,pdebuyl/numpy,anntzer/numpy,jakirkham/numpy,pizzathief/numpy,anntzer/numpy,simongibbons/numpy,simongibbons/numpy,jakirkham/numpy,charris/numpy,anntzer/numpy,anntzer/numpy,jorisvandenbossche/numpy,numpy/numpy,MSeifert04/numpy,jorisvandenbossche/numpy,simongibbons/numpy,grlee77/numpy,ahaldane/numpy,pizzathief/numpy,seberg/numpy,simongibbons/numpy,gfyoung/numpy,ahaldane/numpy,shoyer/numpy,jorisvandenbossche/numpy,pbrod/numpy,abalkin/numpy,shoyer/numpy,MSeifert04/numpy,seberg/numpy,abalkin/numpy,pdebuyl/numpy,jakirkham/numpy,madphysicist/numpy,mattip/numpy,ahaldane/numpy,jorisvandenbossche/numpy,jorisvandenbossche/numpy,rgommers/numpy,pizzathief/numpy,rgommers/numpy,endolith/numpy,jakirkham/numpy,endolith/numpy,WarrenWeckesser/numpy,MSeifert04/numpy,pizzathief/numpy,madphysicist/numpy,mhvk/numpy,mattip/numpy,pizzathief/numpy,mhvk/numpy,WarrenWeckesser/numpy,shoyer/numpy,pbrod/numpy,gfyoung/numpy,numpy/numpy,ahaldane/numpy,simongibbons/numpy,mhvk/numpy,seberg/numpy,madphysicist/numpy,numpy/numpy,endolith/numpy,abalkin/numpy,charris/numpy,rgommers/numpy,pdebuyl/numpy,charris/numpy,ahaldane/numpy,endolith/numpy,WarrenWeckesser/numpy,mattip/numpy,gfyoung/numpy,MSeifert04/numpy,rgommers/numpy,madphysicist/numpy,charris/numpy,pdebuyl/numpy,grlee77/numpy,shoyer/numpy,pbrod/numpy,mhvk/numpy,numpy/numpy,WarrenWeckesser/numpy,jakirkham/numpy,grlee77/numpy,pbrod/numpy,pbrod/numpy,MSeifert04/numpy,shoyer/numpy,grlee77/numpy,mhvk/numpy,mattip/numpy