Is it possible to mix definition variables and constants in an mxMatrix?

The value of each covariate is read from the data as a definition variable ( "data.cov1", "data.cov2" etc) in a matrix named "defCovs"

As the betas are all in one matrix, I'd like to also have an "intercept" column, fixed at 1 in the the defCovs matrix to simplify the arithmetic.

Question: Is it legal to include fixed values along with definition variables in an mxMatrix?

so:


$labels
"intercept" "data.age"
$values
1 0
$free: FALSE FALSE