Another way is to use Nick Cox's -tabcount- which will tabulate missing
values.
**********
clear
set obs 100
set seed 1234567
forv i=1/2 {
g var`i'=1
replace var`i'=2 if uniform()>.4
replace var`i'=3 if uniform()>.3
}
replace var2=4 if var2==3
tabcount var1, v(1/4) zero mat(m1)
tabcount var2, v(1/4) zero mat(m2)
levels var1, local(l1)
levels var2, local(l2)
local l3 : list l1 | l2
local rows : subinstr local l3 " " ",", all
matrix rows = (`rows')'
matrix freq = rows, m1, m2
matrix list freq
Hope this helps,
Scott
> -----Original Message-----
> From: [email protected] [mailto:owner-
> [email protected]] On Behalf Of Nick Winter
> Sent: Wednesday, June 08, 2005 7:03 PM
> To: [email protected]
> Subject: Re: st: Merging matrices
>
> I'm sure there is something better, but what occurs to me is to use -
> svmat-
> and -merge-. Something like this, after the code you've generated:
>
> drop _all
> svmat v1
> rename v11 value
> sort value
> save temp1
> drop _all
> svmat v2
> rename v21 value
> sort value
> merge value using temp1
>
> foreach v in v12 v22 {
> replace `v' = 0 if mi(`v')
> }
> sort value
>
>
> This would need to be generalized a bit, and would need to rename/label
> the
> resulting variables better, etc., but might be a viable approach.
>
> --Nick Winter
>
> At 07:18 PM 6/8/2005, you wrote:
> >Hello all,
> >
> >I am trying to write a program that (in part) displays a special table
> showing
> >the frequency counts of two variables. I am currently using -tabulate- on
> the
> >two variables and extracting the necessary row and frequency names. It's
> then
> >easy to show TWO tables with the frequencies, via simple matrix
> subscripting.
> >The difficulty that showing them in one table imposes is that, unless the
> list
> >of row names is the same in the two variables, displaying the stored
> >frequencies via simple matrix subscripting will line up the rows
> incorrectly.
> >
> >To make this clearer, consider the following code:
> >
> >**********
> >clear
> >set obs 100
> >set seed 1234567
> >forv i=1/2 {
> > g var`i'=1
> > replace var`i'=2 if uniform()>.4
> > replace var`i'=3 if uniform()>.3
> >}
> >replace var2=4 if var2==3
> >tab var1, matcell(freqs1) matrow(nums1)
> >mat v1=(nums1,freqs1)
> >tab var2, matcell(freqs2) matrow(nums2)
> >mat v2=(nums2,freqs2)
> >**********
> >
> >The two resulting matrices will look as follows:
> >
> >. mat list v1
> >
> >v1[3,2]
> > c1 c1
> >r1 1 15
> >r2 2 28
> >r3 3 57
> >
> >. mat list v2
> >
> >v2[3,2]
> > c1 c1
> >r1 1 21
> >r2 2 25
> >r3 4 54
> >
> >What I would like to create is a hypothetical v3, which looks like this:
> >
> >v3[4,3]
> > c1 c1 c1
> >r1 1 15 21
> >r2 2 28 25
> >r3 3 57 0
> >r4 4 0 54
> >
> >I've been poring over the -matrix- commands, and I just can't figure out
> a way
> >to create this matrix. I've also looked at -tabcount- and -groups-,
> without
> >success (I know that Nick Cox wrote on these recently, but our library's
> copy
> >of the SJ is at the bindery, worse luck!).
> >
> >Does anyone have any ideas for producing v3, as described above?
> >
> >Thanks,
> >John-Paul Ferguson
> >*
> >* For searches and help try:
> >* http://www.stata.com/support/faqs/res/findit.html
> >* http://www.stata.com/support/statalist/faq
> >* http://www.ats.ucla.edu/stat/stata/
>
> --------------------------------------------------------
> Nicholas Winter 607.255.8819 t
> Assistant Professor 607.255.4530 f
> Department of Government [email protected] e
> 308 White Hall falcon.arts.cornell.edu/nw53 w
> Cornell University
> Ithaca, NY 14853-4601
>
> *
> * For searches and help try:
> * http://www.stata.com/support/faqs/res/findit.html
> * http://www.stata.com/support/statalist/faq
> * http://www.ats.ucla.edu/stat/stata/
*
* For searches and help try:
* http://www.stata.com/support/faqs/res/findit.html
* http://www.stata.com/support/statalist/faq
* http://www.ats.ucla.edu/stat/stata/
