mapping coords

anyone want to tell me how to map coords from [-1,1] to [0,1]? much appreciated

Actually there are infinitely many mappings from [-1,+1] to [0,1], but I assume you mean the affine transformation T specified by T(-1)=0 and T(+1)=1.

In general you can do an affine mapping T: x->x’ specified by T(a)=p and T(b)=q like this:


or in your specific case: