i am successfully transforming a 2D plot, when doing the exact analog thing to a 3D plot i get the error message
Error, (in t) invalid input: unknown uses a 3rd argument, z, which is missing
i have no idea what's going on, please advise.
i made a minimum example:
this works:
> restart:with(plots):with(plottools):
> norm2:=x->x[1]^2+x[2]^2:
> N:=[0,1]:
> phi:=(x,y)->N+2*([x,y]-N)/norm2([x,y]-N):