scalars from a vector in the calculator filter

It seems there is a lot of documentation about how to use the calculator to produce a vector from scalars. Is it possible to get a component of a vector as a scalar in the calculator filter? I want to get the z value of coords so I can color by it, but I also have other situations with non coordinate vectors where I want to get the ith element as a scalar.
Thanks, --John.

The Calculator filter exposes all components of a coodinates and input vectors under the Scalars menu. Just pick the one of interest e.g. Normals_Z as expression on the Calculator applied to a Sphere source will extract the z-value for the normals.