Chief Delphi - calling all MatLab gurus...

Chief Delphi (http://www.chiefdelphi.com/forums/index.php)

- Math and Science (http://www.chiefdelphi.com/forums/forumdisplay.php?f=70)

- - calling all MatLab gurus... (http://www.chiefdelphi.com/forums/showthread.php?t=128821)

Ether

04-15-2014 06:40 PM

calling all MatLab gurus...

I have an M by N matrix A and an M by 1 column vector b.

I want to find the N by 1 column vector x which minimizes sum(abs(A*x-b)).

What is the recommended way to do this in MatLab?

Jared Russell

04-15-2014 08:58 PM

Re: calling all MatLab gurus...

I'd use linprog and solve the same linear program as in the Python thread.

Ether

04-15-2014 11:43 PM

Re: calling all MatLab gurus...

1 Attachment(s)

Attached is an XLS spreadsheet with a 256-by-64 A matrix and a 256-by-1 b column vector.

Using your favorite tool or language, find the 64-by-1 column vector x which minimizes sum(abs(A*x-b)). Show your work.

Any takers?

Ether

04-17-2014 03:56 PM

Re: calling all MatLab gurus...

1 Attachment(s)

Quote:

Originally Posted by Ether (Post 1374458)

If there's anyone out there in CD land working on the above, please use the attached alternate b vector. It's more effective at revealing possible flaws in the solution.

The Doctor

04-17-2014 05:09 PM

Re: calling all MatLab gurus...

Why?

Ether

04-19-2014 05:16 PM

Re: calling all MatLab gurus...

Why what?

Ether

05-04-2014 04:00 PM

Re: calling all MatLab gurus...

Quote:

Originally Posted by Ether (Post 1374326)

I have an M by N matrix A and an M by 1 column vector b.

I want to find the N by 1 column vector x which minimizes sum(abs(A*x-b)).

What is the recommended way to do this in MatLab?

Turns out, this is a very interesting problem.

See discussion in this thread:

http://www.chiefdelphi.com/forums/sh...48&postcount=6

All times are GMT -5. The time now is 04:51 AM.