Notice: On April 23, 2014, Statalist moved from an email list to a forum, based at statalist.org.
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: st: RE: getting the nth column name
From
Nick Cox <[email protected]>
To
[email protected]
Subject
Re: st: RE: getting the nth column name
Date
Tue, 6 Nov 2012 21:38:49 +0000
These are good solutions once the data are read in.
If the problem is to get at the third variable name before the dataset
is read in, something like
d using auto, varlist
use `: word 3 of `r(varlist)'' using auto
is needed.
In addition, -unab- is a neglected command here. See its documentation and/or
Cox, N.J. 2010. Stata tip 91: Putting unabbreviated varlists into
local macros. Stata Journal 10: 503-504.
A notable small difference between Joerg's solution and David's is
that Joerg used `= ' rather ` '. It won't bite for the 3rd variable
name, but the equals sign will truncate the string it evaluates, for
reasons explained in
SJ-8-4 pr0045 . . . . . . . . Stata tip 70: Beware the evaluating equal sign
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . N. J. Cox
Q4/08 SJ 8(4):586--587 (no commands)
tip explaining the pitfall of losing content in a macro
because of limits on the length of string expressions
Nick
Joerg Luedicke
You can use -ds- (-help ds-) to create a variable list and put the
name of the third variable in a local macro (-help extended_fcn-) for
further usage:
*----------------------
clear
sysuse auto
qui ds
local third : word 3 of `=r(varlist)'
sum `third'
*----------------------
David Radwin
> You can put the variable name in a local macro, like this:
>
> . ds
> . local var3 : word 3 of `r(varlist)'
> . describe `var3'
Pradipto Banerjee
>> I want to write a code to read the 3rd column from a few different
>> datasets. My issue is that the 3rd column can have different names in
>> different datasets. Is there any function or command that returns the
> name
>> of the Nth column ?
>>
>> For instance, suppose file F1 has the 3rd column as F1xyz and F2 has the
>> 3rd column as F2abc, I want a generic way to refer to F1xyz and F2abc
> with
>> an -ado- program?
*
* 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/