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From | Nick Cox <njcoxstata@gmail.com> |
To | statalist@hsphsun2.harvard.edu |
Subject | Re: st: Re: Stata matrix to Mata matrix form |
Date | Thu, 1 Nov 2012 16:34:49 +0000 |
You've lost me. What is mat_S2[1,2]? Nick On Thu, Nov 1, 2012 at 3:39 PM, Bianca B. <bianca268@yahoo.com> wrote: > Nick, you're right, I'm sorry. I didn't specify that I need to turn my lower-triangular matrix into a symmetrical matrix by reflecting the lower triangular elements across the diagonal. So starting from this matrix > > mat_S2 > > 1 2 > +---------+ > 1 | 0 | > 2 | 1 0 > | > +---------+ > I'd like to obtain a matrix like that > > 1 2 > +---------+ > 1 | 0 1 | > 2 | 1 0 | > +---------+ > > > > > --- On Thu, 11/1/12, Nick Cox <njcoxstata@gmail.com> wrote: > >> From: Nick Cox <njcoxstata@gmail.com> >> Subject: Re: st: Re: Stata matrix to Mata matrix form >> To: statalist@hsphsun2.harvard.edu >> Date: Thursday, November 1, 2012, 8:29 AM >> Looks symmetric to me. >> >> If a matrix is symmetric, Stata says so, and only displays >> the lower >> half (including the principal diagonal). >> >> In your case, Stata is doing exactly that. >> >> Here is another example: >> >> . mata : I(3) >> [symmetric] >> >> 1 2 3 >> +-------------+ >> 1 | 1 | >> 2 | 0 1 | >> 3 | >> 0 0 1 | >> +-------------+ >> >> If this is not what you mean, you'll have to explain what >> "doesn't >> work" means exactly. >> >> Nick >> >> On Thu, Nov 1, 2012 at 3:16 PM, Bianca B. <bianca268@yahoo.com> >> wrote: >> > Dear Nick, >> > >> > Thanks a lot. I converted a lower-triangular matrix >> from stata to mata form to apply the mata makesymmetric >> command but it doesn't work. >> > The command is >> > >> > : makesymmetric(mat_S2) >> > [symmetric] >> > 1 2 >> > +---------+ >> > 1 | 0 | >> > 2 | 1 0 >> | >> > +---------+ >> > >> > Would you have any suggestion? >> > Best, >> > Bianca >> > >> > >> > >> > . mat foo = J(6,7,42) >> > >> > . mat li foo >> > >> > foo[6,7] >> > c1 c2 c3 >> c4 c5 c6 c7 >> > r1 42 42 42 42 42 >> 42 42 >> > r2 42 42 42 42 42 >> 42 42 >> > r3 42 42 42 42 42 >> 42 42 >> > r4 42 42 42 42 42 >> 42 42 >> > r5 42 42 42 42 42 >> 42 42 >> > r6 42 42 42 42 42 >> 42 42 >> > >> > . mata : mat_foo = st_matrix("foo") >> > >> > . mata : mat_foo >> > 1 >> 2 3 4 5 >> 6 7 >> > >> +------------------------------------+ >> > 1 | >> 42 42 42 42 42 42 42 >> | >> > 2 | >> 42 42 42 42 42 42 42 >> | >> > 3 | >> 42 42 42 42 42 42 42 >> | >> > 4 | >> 42 42 42 42 42 42 42 >> | >> > 5 | >> 42 42 42 42 42 42 42 >> | >> > 6 | >> 42 42 42 42 42 42 42 >> | >> > >> +------------------------------------+ >> > >> > . mata : st_matrix("foo", mat_foo :/ 7) >> > >> > . mat li foo >> > >> > foo[6,7] >> > c1 c2 c3 >> c4 c5 c6 c7 >> > >> r1 6 6 6 6 6 6 6 >> > >> r2 6 6 6 6 6 6 6 >> > >> r3 6 6 6 6 6 6 6 >> > >> r4 6 6 6 6 6 6 6 >> > >> r5 6 6 6 6 6 6 6 >> > >> r6 6 6 6 6 6 6 6 >> > >> > --- On Thu, 11/1/12, Bianca B. <bianca268@yahoo.com> >> wrote: >> > >> >> From: Bianca B. <bianca268@yahoo.com> >> >> Subject: Stata matrix to Mata matrix form >> >> To: statalist@hsphsun2.harvard.edu >> >> Date: Thursday, November 1, 2012, 7:25 AM >> >> Hi Stata users, >> >> >> >> Does anyone know how can I get stata matrix in mata >> matrix? * * 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/