[R] match function or "=="

[Patrick Burns]

You might want to investigate the
'data.table' package.

On 07/04/2010 16:15, bo wrote:
>
> Hi all,
>
> I have a huge dataset(5000k observations), which contains the daily sales
> for each company.
> If I want to find out the a company with unique company id number, which
> function I should use that is more efficient, match or "=="?  For example,
>
> use<-dataset[!is.na(match(dataset$companyID, 12345)),]
> or
> use<-dataset[dataset$companyID==12345,]
>
> Thank you very much.
>

-- 
Patrick Burns
pburns at pburns.seanet.com
http://www.burns-stat.com
(home of 'Some hints for the R beginner'
and 'The R Inferno')