Notice: On March 31, it was **announced** that Statalist is moving from an email list to a **forum**. The old list will shut down at the end of May, and its replacement, **statalist.org** is already up and running.

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

From |
r.a.nobel@umail.leidenuniv.nl |

To |
statalist@hsphsun2.harvard.edu |

Subject |
Re: st: manipulate ordering of rows matrices |

Date |
Tue, 10 May 2011 10:07:23 +0200 |

Yes I'm sorry. What is correct for me in this particular case, is that for example for columns 3,4&5 (which are in fact dummy codings for a variable consisting of 4 categories) the ones are sorted in an upward diagonal: 0 0 0 0 0 1 0 1 0 1 0 0 But I need this be done generally done as: 0 0 0 1 0 0 0 1 0 0 0 1 I hope this makes it more clear, Alex >Quoting Nick Cox <njcoxstata@gmail.com>: > It would help if you explained the essence of the difference. What > makes X2 sorted correctly? > > Nick > > On Tue, May 10, 2011 at 8:32 AM, <r.a.nobel@umail.leidenuniv.nl> wrote: > > > I'm having trouble with the following in Mata: > > > > From a large matrix X, I need a new matrix with unique values/rows. As an > > example, when I use : > > > > x1 = uniqrows(X) > > > > Then, the matrix given is: > > > > x1 = ( > > 1,0,0,0,0,0,0,0\ > > 1,0,0,0,1,0,0,0\ > > 1,0,0,1,0,0,0,0\ > > 1,0,1,0,0,0,0,0\ > > 1,1,0,0,0,0,0,0\ > > 1,1,0,0,1,0,0,1\ > > 1,1,0,1,0,0,1,0\ > > 1,1,1,0,0,1,0,0 ) > > > > But what I need is: > > > > x2 = ( > > 1,0,0,0,0,0,0,0\ > > 1,0,1,0,0,0,0,0\ > > 1,0,0,1,0,0,0,0\ > > 1,0,0,0,1,0,0,0\ > > 1,1,0,0,0,0,0,0\ > > 1,1,1,0,0,1,0,0\ > > 1,1,0,1,0,0,1,0\ > > 1,1,0,0,1,0,0,1 ) > > > > Of course, this can be done easily for just this matrix, but the problem is > that > > I need the correct matrix as part of an estimation command (thus, the > matrices > > can be different everytime, dependent on the dataset at hand), so I need a > sort > > of general way to ensure the matrix is always sorted correctly. However, > I've > > not find a working strategy yet. > > * > * 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/

**Follow-Ups**:**Re: st: manipulate ordering of rows matrices***From:*Nick Cox <njcoxstata@gmail.com>

**References**:**st: manipulate ordering of rows matrices***From:*r.a.nobel@umail.leidenuniv.nl

**Re: st: manipulate ordering of rows matrices***From:*Nick Cox <njcoxstata@gmail.com>

- Prev by Date:
**Re: st: using value of one variable to read value of specific other variable out of a list of variables** - Next by Date:
**Re: st: manipulate ordering of rows matrices** - Previous by thread:
**Re: st: manipulate ordering of rows matrices** - Next by thread:
**Re: st: manipulate ordering of rows matrices** - Index(es):