[R] Analogy for %in% for the whole columns (rather than individual values)

[Dimitri Liakhovitski]

Thank you very much! I tried %in% and it did not work. However == works!
Thank you!

On Thu, Mar 26, 2009 at 3:05 PM, Fredrik Karlsson <dargosch at gmail.com> wrote:
> Hi Dimitri,
>
> What about this:
>
>
>> with(a, x == y) -> a$equal
>> a
>      x    y equal
> 1 john mary FALSE
> 2 mary mary  TRUE
> 3 mary john FALSE
> 4 john john  TRUE
>
> /Fredrik
>
> On Thu, Mar 26, 2009 at 7:48 PM, Dimitri Liakhovitski <ld7631 at gmail.com>
> wrote:
>>
>> Hello!
>>
>> I have a matrix a with 2 variables (see below) that contain character
>> strings.
>> I need to create a 3rd variable that contains True if the value in
>> column x is equal to the value in column y. The code below does it.
>>
>> a<-data.frame(x=c("john", "mary", "mary",
>> "john"),y=c("mary","mary","john","john"))
>> a$x<-as.character(a$x)
>> a$y<-as.character(a$y)
>> a$equal<-NA
>> for(i in 1:nrow(a)) {a[i,3]<-a[i,1] %in% a[i,2]}
>>
>> I was wondering if one can do it faster, without doing it row-by-row
>> as I did it. Maybe there is a faster way to compare 2 columns?
>>
>> Thank you very much!
>>
>> --
>> Dimitri Liakhovitski
>> MarketTools, Inc.
>> Dimitri.Liakhovitski at markettools.com
>>
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>
>
>
> --
> "Life is like a trumpet - if you don't put anything into it, you don't get
> anything out of it."
>



-- 
Dimitri Liakhovitski
MarketTools, Inc.
Dimitri.Liakhovitski at markettools.com