R help - Apr 2014 - Problem with new(er) R version's matrix package

Dear Rs,

I am re-executing some older code. It does work in the ancient R 2.12.0 which I
still have on my PC but with the new version R 3.1.0 it does not work any more
(but some other new stuff, which won't work with 2.12).

The problem arises in context with the systemfit package using the matrix
package. In R 3.1.0 the following error is thrown:
Error in as.matrix(solve(W, tol = solvetol)[1:ncol(xMat), 1:ncol(xMat)]) : error
in evaluating the argument 'x' in selecting a method for function
'as.matrix': Error in .solve.sparse.dgC(as(a, "dgCMatrix"), b
= b, tol = tol) : LU computationally singular: ratio of extreme entries in
|diag(U)| = 7.012e-39

However, I have no clue what I can do about this. Was there some change in the
defaults of the matrix package? I couldn't find anything apparent in the
changelog. As the same code works in R 2.12.0, I suppose that the problem is not
my data.

If anyone has an idea about this, I would really appreciate your hints.

Thanks!
Werner

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On Apr 25, 2014, at 9:17 AM, Werner W. wrote:
> Dear Rs,
> 
> I am re-executing some older code. It does work in the ancient R 2.12.0
which I still have on my PC but with the new version R 3.1.0 it does not work
any more (but some other new stuff, which won't work with 2.12).
> 
> The problem arises in context with the systemfit package using the matrix
package. In R 3.1.0 the following error is thrown:
> Error in as.matrix(solve(W, tol = solvetol)[1:ncol(xMat), 1:ncol(xMat)]) :
error in evaluating the argument 'x' in selecting a method for function
'as.matrix': Error in .solve.sparse.dgC(as(a, "dgCMatrix"), b
= b, tol = tol) : LU computationally singular: ratio of extreme entries in
|diag(U)| = 7.012e-39
> 
> However, I have no clue what I can do about this. Was there some change in
the defaults of the matrix package? I couldn't find anything apparent in the
changelog. As the same code works in R 2.12.0, I suppose that the problem is not
my data.
You have not told us what version of the Matrix package you were using. As such
I would suggest that you review the Changelog which is a link for the CRAN page
for pkg:Matrix and go back 4 years or so since R major versions change about
once a year.

http://cran.r-project.org/web/packages/Matrix/ChangeLog

> 
> If anyone has an idea about this, I would really appreciate your hints.
> 
> Thanks!
> Werner
> 
> 	[[alternative HTML version deleted]]
> 
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