Thanks for the prompt and clear reply! The simplicity of the solution may have
been why I initially overlooked this approach...
The results look convincing (http://169.237.35.250/~dylan/temp/affine.png),
now I just need to verify that the output from coef() is in the format that I
need it in.
This may sound like a very naive question, but...
give two lists of coordinate pairs (x,y - Cartesian space) is there any simple
way to compute the affine transformation matrix in R.
I have a set of data which is offset from where i know it should be. I have
coordinates of the current data,
Isn't this just a regression (hopefully with a near-zero error).
coef(lm(cbind(xnew, ynew) ~ xold + yold))
should do what I think you are asking for. (I am not clear which
direction you want the transformation, so choose 'old' and 'new'
accordingly.)
On Mon, 28 May 2007, Dylan Beaudette
