Here is my understanding,
Given a unit vector A = x1,y1,z1 in cartesian, to transform into cylindrical just use the transform
A . \rho
A . \phi
Z(cartesian)=Z(cylindrical)
my question is, since x . \rho = cos\phi, is the \phi that I am supposed to use the tan^-1(y1/X1)?
If this is...