Jack and I have recently been working on a new accessor. It's named
"$result" (so far) and it gets you a matrix after execution of
commands that don't have specific accessors of their own but whose
output can reasonably be represented as a matrix.
So far we've implemented this for corr, freq, summary, vif (the BKW
matrix) and xtab (the simple two-variable case only). We have in
mind a few other commands that could benefit from this treatment.
The accessor works a bit like $model, in that each time a supported
command is executed the prior $result matrix (if any) is destroyed
and a new one substituted.
We considered requiring a new option (say, --savemat) to make this
happen (since if the matrix isn't wanted we've wasted some CPU
cycles building it) but our current view is that it's not really