What is dimension of target space?

[transgalactic]

what is dimension of target space??

is it the R^4 on top(which says that we have 4 coordinates like x y z t

or 4 vectors in the matrix (whats it called the total number of the vectors??)

 

[HallsofIvy]

I have no idea what you are talking about! "R^4 on top" of what? 4 vectors in what matrix? I assume that by "target space" you mean the the range of some linear transformation.