[datatable-help] datatable-help Digest, Vol 92, Issue 6

[Serdar Akin]

How about
DT[, .N , by = .(student_fee)]

mån 16 okt. 2017 kl. 12:00 skrev <
datatable-help-request at lists.r-forge.r-project.org>:

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>    1. how to grouping of data in R (memonsalim2008)
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> ----------------------------------------------------------------------
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> Message: 1
> Date: Mon, 16 Oct 2017 01:34:10 -0700 (MST)
> From: memonsalim2008 <memonsalim2008 at yahoo.co.in>
> To: datatable-help at lists.r-forge.r-project.org
> Subject: [datatable-help] how to grouping of data in R
> Message-ID: <1508142850217-0.post at n4.nabble.com>
> Content-Type: text/plain; charset=us-ascii
>
> Hi All,
>
> is it possible in R groping of data ?Please check blow example.
>
>
> student_id  Fee
> 5555            1200
> 5555            1200
> 1111            1200
> 6666            1500
> 6666            1500
> 6666            1000
> 7777            1000
> 8888            1000
> 8888            1000
> 8888            1000
> 8888            1000
>
> output of will be
>
> student_id   count
> 5555              2
> 1111              1
> 6666              3
> 7777              1
> 8888             4
>
>
>
>
>
> --
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> End of datatable-help Digest, Vol 92, Issue 6
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