Re: [R] solve error

From: Dimitris Rizopoulos <dimitris.rizopoulos_at_med.kuleuven.be>
Date: Fri 28 Oct 2005 - 17:28:55 EST

it means that the matrix w is singular; check

all.equal(w[, 1], w[, 4])
all.equal(w[, 2], w[, 3])
# or
qr(w)$rank

you need linearly independent columns!

I hope it helps.

Best,
Dimitris



Dimitris Rizopoulos
Ph.D. Student
Biostatistical Centre
School of Public Health
Catholic University of Leuven

Address: Kapucijnenvoer 35, Leuven, Belgium

Tel: +32/(0)16/336899
Fax: +32/(0)16/337015
Web: http://www.med.kuleuven.be/biostat/
     http://www.student.kuleuven.be/~m0390867/dimitris.htm


>> w
> [,1] [,2] [,3] [,4]
> 1:1 0.0 0.5 0.5 0.0
> 2:1 0.5 0.0 0.0 0.5
> 1:2 0.5 0.0 0.0 0.5
> 2:2 0.0 0.5 0.5 0.0
>
>> solve(w)
> Error in solve.default(w) : Lapack routine dgesv:
> system is exactly singular
>
> what does the error mean?
>
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R-help@stat.math.ethz.ch mailing list
https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html Received on Fri Oct 28 17:29:52 2005

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