I think there does exist the concept of a vec1 value. It's a 1-dimensional vector. Something like just an X coordinate, for example. Their length is their value.
Click on the little thingy under the top right "x" of the ndo window. There you find an option called "map converter". That's what you are looking for.
Added a frame generator for the wall. It scales in the x and y axis without stretching the moulding and the wood grain is going in the right direction for each piece.