#### solving dense singular linear system

```Hello,
I am trying to solve a square system of linear equation Ax=b, with A
singular. Any suggestions about possible MATLAB built-in routines or
user-contributed routines are welcome.

Is it possible to use any of lsqr, cgs, gmres methods? do these give
accurate solution, is any method better than the others.

As I was reading, I came across the topic of matrix deflation and
inflation, anybody know about MATLAB resources related to this topic?

There was also a suggestion to reduce the number of equation by 1 and
then making the matrix consistent. Any insight on this is very
appreciated.

Thanks,
```
 0
fdawoud (1)
5/29/2007 2:49:47 AM
comp.soft-sys.matlab 208209 articles. 6 followers. lunamoonmoon (258) is leader.

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```"Fady Dawoud" <fdawoud@dal.ca> wrote in message
news:ef58558.-1@webcrossing.raydaftYaTP...
> Hello,
> I am trying to solve a square system of linear equation Ax=b, with A
> singular. Any suggestions about possible MATLAB built-in routines or
> user-contributed routines are welcome.
>
> Is it possible to use any of lsqr, cgs, gmres methods? do these give
> accurate solution, is any method better than the others.
>
> As I was reading, I came across the topic of matrix deflation and
> inflation, anybody know about MATLAB resources related to this topic?
>
> There was also a suggestion to reduce the number of equation by 1 and
> then making the matrix consistent. Any insight on this is very
> appreciated.
>
> Thanks,

HELP MLDIVIDE

--
Steve Lord
slord@mathworks.com

```
 0
slord (13693)
5/29/2007 3:44:07 AM
```Fady Dawoud wrote:
>
>
> Hello,
> I am trying to solve a square system of linear equation Ax=b, with
> A
> singular. Any suggestions about possible MATLAB built-in routines
> or
> user-contributed routines are welcome.
>
> Is it possible to use any of lsqr, cgs, gmres methods? do these
> give
> accurate solution, is any method better than the others.
>
> As I was reading, I came across the topic of matrix deflation and
> inflation, anybody know about MATLAB resources related to this
> topic?
>
> There was also a suggestion to reduce the number of equation by 1
> and
> then making the matrix consistent. Any insight on this is very
> appreciated.
>
> Thanks,

x = pinv(A)*b

HTH,
John
```
 0
woodchips (7942)
5/29/2007 10:41:05 AM
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