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Re: st: Mata not computing eigenvectors/values
From
Zachary Neal <[email protected]>
To
[email protected]
Subject
Re: st: Mata not computing eigenvectors/values
Date
Mon, 10 Jan 2011 14:28:04 -0500
Steven,
Yes, using Matthew's commands I am able to get the correct values.
But, symeigensystem still doesn't work, even after reinstalling and
after trying it on a different machine.
I suppose I'll get in touch with support.
Thanks for your help,
Zachary
On Mon, Jan 10, 2011 at 2:14 PM, Steven Samuels <[email protected]> wrote:
> Zachary
>
> What happens if you run Mathew's Mata commands (below)?. All three Mata
> versions and your Stata matrix commands produce the same values for me. In
> any case, perhaps there is something wrong with your Mata installation. Try
> re-installing Stata and bringing it up to date. If that doesn't work, I
> suggest that you contact support.
>
> Steve
>
> **********
> eigensystem(A,X=.,L=.)
> L'
> lefteigensystem(A,Y=.,M=.)
> M
> ***********
>
> I would bet there
> On Jan 10, 2011, at 1:39 PM, Zachary Neal wrote:
>
> Sorry, that was a careless typo in my original message. Steven is
> right, it should have read:
>
> symeigensystem(A,eigenvector,eigenvalue)
>
> However, even with that correction, the outputs - eigenvector and
> eigenvalue - are empty.
>
> In contrast, if I attempt the same thing in stata, using:
> matrix A = (0,0,0,0,0,1,0,1,0,0,0,0,0 \ ///
> 0,0,0,0,0,0,0,1,0,1,0,0,0 \ ///
> 0,0,0,1,0,1,1,0,1,0,1,1,1 \ ///
> 0,0,1,0,0,0,1,0,0,0,0,0,0 \ ///
> 0,0,0,0,0,0,0,1,0,0,0,0,0 \ ///
> 1,0,1,0,0,0,0,0,0,0,0,1,0 \ ///
> 0,0,1,1,0,0,0,0,0,0,0,0,0 \ ///
> 1,1,0,0,1,0,0,0,0,0,0,0,0 \ ///
> 0,0,1,0,0,0,0,0,0,0,0,0,0 \ ///
> 0,1,0,0,0,0,0,0,0,0,0,0,0 \ ///
> 0,0,1,0,0,0,0,0,0,0,0,0,0 \ ///
> 0,0,1,0,0,1,0,0,0,0,0,0,0 \ ///
> 0,0,1,0,0,0,0,0,0,0,0,0,0)
> matrix symeigen eigenvectors eigenvalues = A
> matrix list eigenvectors
> matrix list eigenvalues
>
> I am able to get the correct eigenvectors/values.
>
> I'm still not sure why this seems to work in stata, but not in mata.
>
> On Mon, Jan 10, 2011 at 10:15 AM, Steven Samuels <[email protected]>
> wrote:
>>
>> -
>> Zachary's code works for me if I substitute "A" for "network" in the
>> -symeigensytem()- command:
>>
>> symeigensystem(A,eigenvector,eigenvalue)
>>
>>
>> Steve
>> Stata 11,1 OS X 10.5.8
>>
>> On Jan 9, 2011, at 9:22 PM, Matthew J Baker wrote:
>>
>> While I am not sure about why the symeigensystem command isn't working,
>> the
>> problem might have something to do with the "A" matrix being rank
>> deficient.
>> In any case, I find that the commands:
>>
>> eigensystem(A,X=.,L=.)
>>
>> and
>>
>> lefteigensystem(A,Y=.,M=.)
>>
>> both generate values for eigenvalues and eigenvectors for the
>> aforementioned
>> A matrix (collected in X and L, and Y and M, respectively).
>>
>> Matt Baker
>>
>> ---- Original message ----
>>>
>>> Date: Sun, 9 Jan 2011 17:45:19 -0500
>>> From: [email protected] (on behalf of Zachary Neal
>>> <[email protected]>)
>>> Subject: st: Mata not computing eigenvectors/values
>>> To: [email protected]
>>>
>>> Running the commands below, mata does not yield any eigenvectors or
>>> eigenvalues. Computing eigenvectors/values in stata using matrix
>>> symeigen seems to work without a problem. Any help would be
>>> appreciated.
>>>
>>> mata
>>> A = (0,0,0,0,0,1,0,1,0,0,0,0,0 \ ///
>>> 0,0,0,0,0,0,0,1,0,1,0,0,0 \ ///
>>> 0,0,0,1,0,1,1,0,1,0,1,1,1 \ ///
>>> 0,0,1,0,0,0,1,0,0,0,0,0,0 \ ///
>>> 0,0,0,0,0,0,0,1,0,0,0,0,0 \ ///
>>> 1,0,1,0,0,0,0,0,0,0,0,1,0 \ ///
>>> 0,0,1,1,0,0,0,0,0,0,0,0,0 \ ///
>>> 1,1,0,0,1,0,0,0,0,0,0,0,0 \ ///
>>> 0,0,1,0,0,0,0,0,0,0,0,0,0 \ ///
>>> 0,1,0,0,0,0,0,0,0,0,0,0,0 \ ///
>>> 0,0,1,0,0,0,0,0,0,0,0,0,0 \ ///
>>> 0,0,1,0,0,1,0,0,0,0,0,0,0 \ ///
>>> 0,0,1,0,0,0,0,0,0,0,0,0,0)
>>> eigenvector = 0
>>> eigenvalue = 0
>>> symeigensystem(network,eigenvector,eigenvalue)
>>> eigenvector
>>> eigenvalue
>>> end
>>>
>>> --
>>> Zachary Neal, PhD
>>> Department of Sociology
>>> Michigan State University
>>> [email protected]
>>> http://www.msu.edu/~zpneal
>>> *
>>> * For searches and help try:
>>> * http://www.stata.com/help.cgi?search
>>> * http://www.stata.com/support/statalist/faq
>>> * http://www.ats.ucla.edu/stat/stata/
>>
>> *
>> * For searches and help try:
>> * http://www.stata.com/help.cgi?search
>> * http://www.stata.com/support/statalist/faq
>> * http://www.ats.ucla.edu/stat/stata/
>>
>> *
>> * For searches and help try:
>> * http://www.stata.com/help.cgi?search
>> * http://www.stata.com/support/statalist/faq
>> * http://www.ats.ucla.edu/stat/stata/
>>
>
>
>
> --
> Zachary Neal, PhD
> Department of Sociology
> Michigan State University
> [email protected]
> http://www.msu.edu/~zpneal
>
> *
> * For searches and help try:
> * http://www.stata.com/help.cgi?search
> * http://www.stata.com/support/statalist/faq
> * http://www.ats.ucla.edu/stat/stata/
>
> *
> * For searches and help try:
> * http://www.stata.com/help.cgi?search
> * http://www.stata.com/support/statalist/faq
> * http://www.ats.ucla.edu/stat/stata/
>
--
Zachary Neal, PhD
Department of Sociology
Michigan State University
[email protected]
http://www.msu.edu/~zpneal
*
* For searches and help try:
* http://www.stata.com/help.cgi?search
* http://www.stata.com/support/statalist/faq
* http://www.ats.ucla.edu/stat/stata/