Re: st: compare files, vars only

[Austin Nichols <austinnichols@gmail.com>]

David Kantor <kantor.d@att.net>:
No, but see -vlc- on SSC.
To compare sets of variables, you could just

prog cvar, rclass
 qui use in 1 using `"`1'"'
 unab f: _all
 qui use in 1 using `"`2"'
 unab g: _all
 loc i: list f & g
 di as txt `"In `1'"' _n as res "`f'"
 di as txt `"In `2'"' _n as res "`g'"
 di as txt "In both" _n as res "`i'"
 if "`i'"=="" di as err "No variables in common"
 return local file1 `"`1'"'
 return local vars1 `f'
 return local file2 `"`2'"'
 return local vars2 `g'
 return local both `i'
end
cvar "`c(sysdir_base)'n/nlsw88" "`c(sysdir_base)'a/auto"

Or did you want to compare an arbitrary number of files?  Also easy
with -mac shift- :

prog cvars, rclass
 loc n=1
 while `"`1'"'!="" {
 qui use in 1 using `"`1'"'
 unab f`n': _all
 di as txt `"In `1'"' _n as res "`f`n''"
 return local file`n' `"`1'"'
 return local vars`n' `f`n''
 if `n'==2 loc f: list f1 & f2
 else loc f: list f & f`n'
 loc n=`n'+1
 mac sh
 }
 di as txt "In all files" _n as res "`f'"
 if "`i'"=="" di as err "No variables in common"
 return local all "`f'"
end
cvars "`c(sysdir_base)'n/nlsw88" "`c(sysdir_base)'a/auto"
"`c(sysdir_base)'a/auto"

On Thu, Feb 19, 2009 at 10:41 AM, David Kantor <kantor.d@att.net> wrote:
> Hi.
> Does anyone know of a program to compare the sets of variables in two data
> files? What I have in mind is something akin to -cf-, but...
>  it would not compare values -- only the names of variables;
>  it would not care whether the two data files had the same number of
> observations.
>
> I was planning to write such a program, but I wanted to be sure that it
> hadn't already been done.
> Thanks
> --David
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