Fill lower matrix with vector by row, not column
- by mhermans
I am trying to read in a variance-covariance matrix written out by LISREL in the following format in a plain text, whitespace separated file:
0.23675E+01 0.86752E+00 0.28675E+01 -0.36190E+00 -0.36190E+00 0.25381E+01
-0.32571E+00 -0.32571E+00 0.84425E+00 0.25598E+01 -0.37680E+00 -0.37680E+00
0.53136E+00 0.47822E+00 0.21120E+01 -0.37680E+00 -0.37680E+00 0.53136E+00
0.47822E+00 0.91200E+00 0.21120E+01
This is actually a lower diagonal matrix (including diagonal):
0.23675E+01
0.86752E+00 0.28675E+01
-0.36190E+00 -0.36190E+00 0.25381E+01
-0.32571E+00 -0.32571E+00 0.84425E+00 0.25598E+01
-0.37680E+00 -0.37680E+00 0.53136E+00 0.47822E+00 0.21120E+01
-0.37680E+00 -0.37680E+00 0.53136E+00 0.47822E+00 0.91200E+00 0.21120E+01
I can read in the values correctly with scan() or read.table(fill=T).
I am however not able to correctly store the read-in vector in a matrix. The following code
S <- diag(6)
S[lower.tri(S,diag=T)] <- d
fills the lower matrix by column, while it should fill it by row.
Using matrix() does allow for the option byrow=TRUE, but this will fill in the whole matrix, not just the lower half (with diagonal).
Is it possible to have both: only fill the lower matrix (with diagonal) and do it by row?
(separate issue I'm having: LISREL uses 'D+01' while R only recognises 'E+01' for scientific notation. Can you change this in R to accept also 'D'?)