Re: [R] impossible to invert a spam-object, but possible when it's a matrix-object

2013-02-11 Thread Berend Hasselman
On 11-02-2013, at 15:00, "Camarda, Carlo Giovanni" wrote: > Dear Uwe, > > thanks for the response. > I knew my matrix was almost singular, but is there any way to implement the > algorithm is solve(base) with a spam-matrix? > > As workaround, I might add a ridge penalty: > >ApP <- A+10^

Re: [R] impossible to invert a spam-object, but possible when it's a matrix-object

2013-02-11 Thread Uwe Ligges
in, Giancarlo From: Uwe Ligges [lig...@statistik.tu-dortmund.de] Sent: Saturday, February 09, 2013 8:04 PM To: Camarda, Carlo Giovanni Cc: r-h...@stat.math.ethz.ch Subject: Re: [R] impossible to invert a spam-object, but possible when it's a matrix-object On 05.02.2013 13:

Re: [R] impossible to invert a spam-object, but possible when it's a matrix-object

2013-02-11 Thread Camarda, Carlo Giovanni
ize other parts of my model. Thanks again, Giancarlo From: Uwe Ligges [lig...@statistik.tu-dortmund.de] Sent: Saturday, February 09, 2013 8:04 PM To: Camarda, Carlo Giovanni Cc: r-h...@stat.math.ethz.ch Subject: Re: [R] impossible to invert a spam-object,

Re: [R] impossible to invert a spam-object, but possible when it's a matrix-object

2013-02-09 Thread Uwe Ligges
On 05.02.2013 13:29, Camarda, Carlo Giovanni wrote: Dear R-users, a question concerning sparse matrices in package "spam" (spam_0.29-2). On one hand I have a spam object (n X n) from which I cannot compute the inverse. On the other hand, if I convert this object in a plain matrix, I can fin

[R] impossible to invert a spam-object, but possible when it's a matrix-object

2013-02-05 Thread Camarda, Carlo Giovanni
Dear R-users, a question concerning sparse matrices in package "spam" (spam_0.29-2). On one hand I have a spam object (n X n) from which I cannot compute the inverse. On the other hand, if I convert this object in a plain matrix, I can find the inverse without any problem. Specifically I get t