Re: [Gretl-devel] foreign R functions and matrix return values
Am 21.10.2016 um 16:38 schrieb Allin Cottrell:
I don't know enough about R's sparse matrices to say exactly what the
'matrix' returned by fcheck consists of, but it looks kinda
funny if you print it in R itself:
m1
[,1]
[1,] 0.8048351
[2,] -0.9528827
[3,] 1.42894
[4,] ?
</R>
Well but that seems to stem from "glueing" together the two matrices
with non-matching dimensions. If you directly look at the initial sparse
matrix in R, here's what I get:
2 x 3 sparse Matrix of class "ngCMatrix"
[1,] . | .
[2,] . . |
The fact that there's missings in there is due to the incomplete
initialization, where only the locations of the non-zeros were
specified, not their values.
So if I use rbind() on a mixture of sparse and dense matrices in R, I get:
<R-sessionpart>
m3 <- sparseMatrix(c(1,2), c(2,3))
m4 <- matrix(rnorm(3), ncol=3)
rbind(m3, m4)
3 x 3 sparse Matrix of class "dgCMatrix"
[1,] . 1.0000000 .
[2,] . . 1.000000
[3,] -1.934421 -0.6477288 1.069744
</R-sessionpart>
Apparently R then automatically puts defaults (1.0) into the missing
places. The transfer to gretl then works fine.
thanks,
sven