[R] what is the faster way to search for a pattern in a few million entries data frame ?

[Fabien Tarrade]

Hi Jim,

I didn't know this one. I will have a look.

Thanks
Cheers
Fabien
> Hi Fabien,
> I was going to send this last night, but I thought it was too simple.
> Runs in about one millisecond.
>
> df<-data.frame(freq=runif(1000),
>   strings=apply(matrix(sample(LETTERS,10000,TRUE),ncol=10),
>   1,paste,collapse=""))
> match.ind<-grep("DF",df$strings)
> match.ind
>   [1]   2  11  91 133 169 444 547 605 734 943
>
> Jim

-- 
Dr Fabien Tarrade

Quantitative Analyst/Developer - Data Scientist

Senior data analyst specialised in the modelling, processing and 
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