[R] Merging dataframes

[peter dalgaard]

I'd expect more like

setdiff(A$key, B$key) 

and vice versa. Or, if you want the actual rows

A[!(A$key %in% B$key),]

or for the row numbers

which(!(A$key %in% B$key))


-pd




> On 1 May 2018, at 12:48 , Rui Barradas <ruipbarradas using sapo.pt> wrote:
> 
> Hello,
> 
> Is it something like this that you want?
> 
> x <- data.frame(a = c(1:3, 5, 5:10), b = c(1:7, 7, 9:10))
> y <- data.frame(a = 1:10, b = 1:10)
> 
> which(x != y, arr.ind = TRUE)
> 
> 
> Hope this helps,
> 
> Rui Barradas
> 
> On 5/1/2018 11:35 AM, Chintanu wrote:
>> Hi,
>> May I please ask how I do the following in R. Sorry - this may be trivial,
>> but I am struggling here for this.
>> For two dataframes (A and B), I wish to identify (based on a primary
>> key-column present in both A & B) -
>> 1. Which records (rows) of A did not match with B, and
>> 2. Which records of B did not match with A ?
>> I came across a setdt function while browsing, but when I tried it, it says
>> - Could not find function "setdt".
>> Overall, if there is any way of doing it (preferably in some simplified
>> way), please advise.
>> Many thanks in advance.
>> regards,
>> Tito
>> 	[[alternative HTML version deleted]]
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>> 
> 
> ______________________________________________
> R-help using r-project.org mailing list -- To UNSUBSCRIBE and more, see
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> and provide commented, minimal, self-contained, reproducible code.

-- 
Peter Dalgaard, Professor,
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