Is there a way to export contiguity weight matrix as .gal file?

[Zvonimir Kulis]

Hello,

I apologize if I missed it somewhere, but please help me. Is there a way, after I create a spatial weight matrix (contiguity) using Stata's option spmatrix create spmatrix create to export this matrix, but in .gal format so that I can import it in GeoDa?

Now I do not need it, but it would be useful for .gwt files too.

Thank you a lot for your help.

[Rafal Raciborski]

I would suggest using the user-written spmat command to create a spatial-matrix object and exporting as such:

// create a toy spmat object
set seed 10101
mata:
    n = 100
    W = runiform(n,n) :> .9
    _makesymmetric(W)
    _diag(W,0)
end
spmat putmatrix spobj W, replace norm(row)

// example of .gal file
spmat export spobj using mydata.gal, nlist replace
type mydata.gal, lines(11)

// example of .gwt file
spmat getmatrix spobj W
capture erase mydata.gwt
mata:
    fh = fopen("mydata.gwt", "w")
    n = rows(W)
    for (i=1; i<=n; i++) {
        for (j=1; j<=n; j++) {
            if (W[i,j]) {
                line = sprintf("%g %g %g",i,j,W[i,j])
                fput(fh,line)
            }
        }
    }
    fclose(fh)
end
type mydata.gwt, lines(11)

// clean up
capture erase mydata.gal
capture erase mydata.gwt

[Zvonimir Kulis]

Thank you a lot