Import numpy for exp and sqrt.
Import numpy for exp and sqrt.

SiccarPoint/landlab,Carralex/landlab,ManuSchmi88/landlab,amandersillinois/landlab,amandersillinois/landlab,RondaStrauch/landlab,cmshobe/landlab,csherwood-usgs/landlab,RondaStrauch/landlab,cmshobe/landlab,landlab/landlab,Carralex/landlab,ManuSchmi88/landlab,ManuSchmi88/landlab,Carralex/landlab,laijingtao/landlab,RondaStrauch/landlab,decvalts/landlab,decvalts/landlab,landlab/landlab,csherwood-usgs/landlab,SiccarPoint/landlab,landlab/landlab,laijingtao/landlab,cmshobe/landlab