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

[Fabien Tarrade]

Hi Duncan,
> Didn't you post the same question yesterday?  Perhaps nobody answered 
> because your question is unanswerable.
sorry, I got a email that my message was waiting for approval and when I 
look at the forum I didn't see my message and this is why  I sent it 
again and this time I did check that the format of my message was text 
only. Sorry for the noise.
> You need to describe what the strings are like and what the patterns 
> are like if you want advice on speeding things up.
my strings are 1-gram up to 5-grams (sequence of 1 work up to 5 words) 
and I am searching for the frequency in my DF of the strings starting 
with a sequence of few words.

I guess these days it is standard to use DF with millions of entries so 
I was wondering how people are doing that in the faster way.

Thanks
Cheers
Fabien

-- 
Dr Fabien Tarrade

Quantitative Analyst/Developer - Data Scientist

Senior data analyst specialised in the modelling, processing and 
statistical treatment of data.
PhD in Physics, 10 years of experience as researcher at the forefront of 
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Fascinated by finance and data modelling.

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