Notice: On April 23, 2014, Statalist moved from an email list to a forum, based at statalist.org.

# RE: st: RE: RE: Sorting rows in Mata

 From Simone Angioloni To "statalist@hsphsun2.harvard.edu" Subject RE: st: RE: RE: Sorting rows in Mata Date Mon, 24 Feb 2014 18:05:09 +0000

```Hi Nick,

I did it, but it does not work.

mymat=(0,3,2,4\3,0,1,6\2,1,0,5\4,6,5,0)
sort(mymat', 1)'

And this is the output:
1   2   3   4
+-----------------+
1 |  0   2   3   4  |
2 |  3   1   0   6  |
3 |  2   0   1   5  |
4 |  4   5   6   0  |
+-----------------+

I do not need to sort only the first row, but all the rows like this:
1   2   3   4
+-----------------+
1 |  0   2   3   4  |
2 |  0   1   3   6  |
3 |  0   1   2   5  |
4 | 0    4   5   6  |
+-----------------+

Thanks.

Simone
________________________________________
From: owner-statalist@hsphsun2.harvard.edu <owner-statalist@hsphsun2.harvard.edu> on behalf of Nick Cox <njcoxstata@gmail.com>
Sent: Monday, February 24, 2014 12:54 PM
To: statalist@hsphsun2.harvard.edu
Subject: Re: st: RE: RE: Sorting rows in Mata

The -sort()- function (not command) can do this for you, with
transposes before and after:

: sort(mymat', 1)'

Nick
njcoxstata@gmail.com

Simone Angioloni

> I knew this command, but it seems not perfectly fit.
>
> My matrix is like this:
>
> mymat=(0,3,2,4\3,0,1,6\2,1,0,5\4,6,5,0)
>
> and I need something like:
>
> 0,2,3,4
> 0,1,3,6
> 0,1,2,5
> 0,4,5,6

Andrew Maurer

> Is mata's sort() function what you're looking for? Try "help mata sort()"
>
> Eg:
> mata
> mymat = (3 \ 1 \ 4 \ 2), (6 \ 7 \ 8 \ 9)
> mymat
> sort(mymat,1)
> end

Simone Angioloni

> Is there a canned command to sort rows in ascending order in Mata without exporting the matrix to Stata and using the rowsort()?
>
> I need to do that in Mata because the marix is very large (more than 1000 by 1000) and once I export the matrix to Stata I have rounding errors that make the matrix slightly different from the original.
*
*   For searches and help try:
*   http://www.stata.com/help.cgi?search
*   http://www.stata.com/support/faqs/resources/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/faqs/resources/statalist-faq/
*   http://www.ats.ucla.edu/stat/stata/
```