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: Beginner Q: 7mil obs - how to add variables
From
"Coleman, Greg" <[email protected]>
To
"[email protected]" <[email protected]>
Subject
RE: st: Beginner Q: 7mil obs - how to add variables
Date
Tue, 8 Oct 2013 20:02:23 +0000
Yes! You did. Thank you. I jumped the gun. A little more exploring showed me it created the new column, newvar, with the total distance for each tailnum repeated in the rows where tailnum occurred again.
-----Original Message-----
From: [email protected] [mailto:[email protected]] On Behalf Of Richard Goldstein
Sent: Tuesday, October 08, 2013 3:37 PM
To: [email protected]
Subject: Re: st: Beginner Q: 7mil obs - how to add variables
as far as I can understand you, what I sent gives you what you want (though Scott's answer does also and compresses several steps into 1)
the display command you used just shows the result in the first observation; did you look at the data? e.g., -browse tailnum distance
newvar-
to go the rest of the way to your graph:
sort tailnum
gr whatever if tailnum!=tailnum[_n-1]
or any of several other ways of reducing
Rich
On 10/8/13 3:25 PM, Coleman, Greg wrote:
> Thanks.
> That just gives me this:
>
>
> . egen newvar=total(distance), by(tailnum)
>
> . display newvar
> 149899
>
> Distance flown by airplane with tail number XXXXXX
>
> I am trying to eventually graph the top N planes by distance flown.
>
> I am getting close (I think) to understanding some features, I can see this:
>
> . bysort tailnum: sum distance
>
> ----------------------------------------------------------------------
> ------------------------------------------------
> -> tailnum = 80009E
>
> Variable | Obs Mean Std. Dev. Min Max
> -------------+--------------------------------------------------------
> distance | 1959 452.6514 216.5128 56 1194
>
> ----------------------------------------------------------------------
> ------------------------------------------------
> -> tailnum = 80019E
>
> Variable | Obs Mean Std. Dev. Min Max
> -------------+--------------------------------------------------------
> distance | 1906 446.2739 222.8244 56 1149
>
>
> But need the arithmetic sum of all the distances for each tailnumber.
>
> -----Original Message-----
> From: [email protected]
> [mailto:[email protected]] On Behalf Of Richard
> Goldstein
> Sent: Tuesday, October 08, 2013 3:01 PM
> To: [email protected]
> Subject: Re: st: Beginner Q: 7mil obs - how to add variables
>
> not completely clear, but it looks like this will get you what you want:
>
> egen newvar=total(Value), by(String)
>
> Rich
>
> On 10/8/13 2:46 PM, Coleman, Greg wrote:
>> Hi
>> My data has 7 million observations and 29 variables. About 10 of the
>> variables are string, and I am trying to get some patterns of the
>> numerical values which are related to the strings. To clarify,
>>
>> String Value
>> AB1234 25
>> CDE789 44
>> F9999 126
>> CDE789 10
>> AB1234 3
>> F9999 100
>>
>> I would like to get output that looks like the sum of values, per string:
>> AB1234 28
>> CDE789 54
>> F9999 226
>>
>> Some strings are just numbers, some are just letters, and some are a combination.
>> Can anyone assist?
>> Thanks!
>> Greg
*
* 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/
*
* 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/