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Re: st: How to solve the matrix equation AX = B for X without using Mata


From   Fernando Rios Avila <f.rios.a@gmail.com>
To   statalist@hsphsun2.harvard.edu
Subject   Re: st: How to solve the matrix equation AX = B for X without using Mata
Date   Thu, 15 Dec 2011 08:18:06 -0500

Also, a bit of traditional matrix algebra:

AX = B
X=inv(A)*B
On Thu, Dec 15, 2011 at 8:11 AM, Tirthankar Chakravarty
<tirthankar.chakravarty@gmail.com> wrote:
> You might want to reconsider Mata. The syntax is no more complicated,
> and there are several advantages to doing numerical computations in
> Mata, with a small overhead:
>
> **********************************
> matrix def A = (0.5, 0.25)'
> matrix def B =  (10, 0.5 \ 0.5, 15)
> mata: st_matrix("C", ///
>        C=lusolve(st_matrix("B"), st_matrix("A")))
> mat li C
> **********************************
> You might also want to read this excellent post by Bill Gould:
> http://www.stata.com/statalist/archive/2011-02/msg00376.html
>
> Unless of course you are constrained by your Stata version...
>
> T
>
> On Thu, Dec 15, 2011 at 4:46 AM, Tiago V. Pereira
> <tiago.pereira@mbe.bio.br> wrote:
>> Dear statalisters,
>>
>> I need to perform the division of matrices A/B, and need to solve the
>> matrix equation AX = B for X.
>>
>> Is there a quick way to solve for X without using Mata?
>>
>> For example, I have the following matrices:
>>
>> matrix A = (0.5, 0.25)
>> matrix B =  (10, 0.5 \ 0.5, 15)
>>
>> and the results should be something like:
>>
>> matrix C = (0.05, 0)
>>
>>
>> Thanks for your time.
>>
>> Tiago
>>
>>
>> *
>> *   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/
>
>
>
> --
> Tirthankar Chakravarty
> tchakravarty@ucsd.edu
> tirthankar.chakravarty@gmail.com
>
> *
> *   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/


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