Bookmark and Share

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]

Re: st: concatenating column vectors


From   Nick Cox <njcoxstata@gmail.com>
To   statalist@hsphsun2.harvard.edu
Subject   Re: st: concatenating column vectors
Date   Sat, 31 Dec 2011 11:04:45 +0000

This looks like elementwise division of  a matrix by a row vector and
as such is supported directly by Mata. No loop needed.

. mata
: y = (1,2,3\4,5,6\7,8,9)

: x = (1,2,3)

: y :/ x
         1     2     3
    +-------------------+
  1 |    1     1     1  |
  2 |    4   2.5     2  |
  3 |    7     4     3  |
    +-------------------+

Nick

On Fri, Dec 30, 2011 at 7:48 AM, Nick Cox <njcoxstata@gmail.com> wrote:
> Show us the code you tried that produced an error.
>
> Nick
>
> On Fri, Dec 30, 2011 at 7:31 AM, Jason Park <loooooo.j8311@gmail.com> wrote:
>> I want to calculate something for each column and concatenate them
>> into a matrix.
>> For a 3x3 matrix, for example, it can be done as follows:
>> matrix Q=uu`i'         /* this is directly from the code I'm using, In
>> fact, I'm trying to modify a code provided by an individual*/
>> matrix Z=vecdiag(Q)
>> matrix P=(Q[1...,1]/Z[1,1],Q[1...,2]/Z[1,2],Q[1...,3]/Z[1,3])
>> And I want to generalized this to NxN case, with and without using a
>> loop both (since it looks like the use of a loop conflicts with some
>> other part of the code, hence generates an error).
>> How can this be done? Please advise.

*
*   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/


© Copyright 1996–2014 StataCorp LP   |   Terms of use   |   Privacy   |   Contact us   |   Site index