Restrict a >= 0 and a != 1 in PowerDistStretch/InvertedPowerDistStretch
Restrict a >= 0 and a != 1 in PowerDistStretch/InvertedPowerDistStretch

aleksandr-bakanov/astropy,pllim/astropy,mhvk/astropy,mhvk/astropy,lpsinger/astropy,mhvk/astropy,dhomeier/astropy,lpsinger/astropy,astropy/astropy,StuartLittlefair/astropy,StuartLittlefair/astropy,pllim/astropy,dhomeier/astropy,saimn/astropy,mhvk/astropy,lpsinger/astropy,dhomeier/astropy,saimn/astropy,astropy/astropy,pllim/astropy,astropy/astropy,StuartLittlefair/astropy,larrybradley/astropy,StuartLittlefair/astropy,pllim/astropy,astropy/astropy,mhvk/astropy,aleksandr-bakanov/astropy,dhomeier/astropy,aleksandr-bakanov/astropy,StuartLittlefair/astropy,larrybradley/astropy,larrybradley/astropy,astropy/astropy,saimn/astropy,larrybradley/astropy,saimn/astropy,saimn/astropy,lpsinger/astropy,aleksandr-bakanov/astropy,larrybradley/astropy,lpsinger/astropy,dhomeier/astropy,pllim/astropy