Statalist


[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: st: AW: compare files, vars only


From   Austin Nichols <austinnichols@gmail.com>
To   statalist@hsphsun2.harvard.edu
Subject   Re: st: AW: compare files, vars only
Date   Thu, 19 Feb 2009 11:39:52 -0500

All--
Loading the whole dataset may hog memory, but
 use in 1 using...
works fine, as shown in my previous post.  -describe- would be
preferable, since it does not load the data in memory at all, but it
does not save a list of variables, and _describe is built-in, hence
not hackable.  It would be possible to write a program that loads no
data and gets all the variable lists, either by parsing the output of
_describe using -file- commands, or as is Sergiy's wont, via a direct
file-access approach.  But it wouldn't be nice if there were a Mata
command to get a view onto a dataset not in memory?

On Thu, Feb 19, 2009 at 11:24 AM, Johannes Geyer <JGeyer@diw.de> wrote:
> what about:
>
>  *************
>  clear*
>  sysuse auto, clear
>  drop  gear_ratio displacement
>  save newauto, replace
>  sysuse auto, clear
>  qui ds
>  loc first `r(varlist)'
>
>  des using auto, varlist
>
>  loc second `r(varlist)'
>  loc diff: list first - second
>  di in red "Differences: `diff'"
>  *************
>
> -describe- does not need to load the dataset which may be of interest here
>
>
> Johannes
>
*
*   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   |   What's new   |   Site index