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<font size="-1"><font face="Arial">Dear all,<br>
<br>
I have a datatable (mydt) with a reference column (code) for
which I set a key, and a set of numeric columns (A ,B, C, D, E).<br>
I obtain this from a serie of script codes, but the issue is
that I have duplicated rows (code), So i want to do is according
to codestation, for each of the columns..<br>
<br>
I could do the following code for one single column:<br>
result<-mydt[,sum(A),by=code]<br>
<br>
but I would like to know if it is possible to do it for each of
the columns, so I get a databable with the same columns with sum
value, group by codestation. Do you have any suggestion?<br>
<br>
I thank you a lot in advance for your answer,<br>
<br>
Best regards,<br>
Emmanuel<br>
<br>
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