[R] Creatng new variable based upon conditions

[Bert Gunter]

Inline.

>
>
> On 07/26/2018 08:58 PM, JEFFERY REICHMAN wrote:
>
>> Given something like ...
>>
>> x <- c(3,2,4,3,5,4,3,2,4,5)
>> y <- c("A","B","B","A","A","A","A","B","A","B")
>> xy <- data.frame(x,y)
>> xy$w <- ifelse(xy$y=="A",xy$w[,x]*10,xy$w[,x]*15 )
>>
>
> You should learn the basics about how to extract or replace part of an
> object, in particular data.frames. You can start by reading the help page
> of ?"Extract".
>

Agreed!

>
> xy$w <- ifelse(xy$y=="A",xy$x*10,xy$x*15 )
>

## or perhaps more simply:
xy$w <- with(xy, ifelse(y=="A", x*10, x*15))

See ?with

Cheers,
Bert




>
> HTH,
> Denes
>
>
>
>> want to see
>>
>>     x y  w
>> 1  3 A 30
>> 2  2 B  30
>> 3  4 B  60
>> 4  3 A  30
>> 5  5 A  50
>> 6  4 A  40
>> 7  3 A  30
>> 8  2 B  30
>> 9  4 A  40
>> 10 5 B  75
>>
>> but I get NA's
>>
>> Jeff
>>
>> ______________________________________________
>> R-help using r-project.org mailing list -- To UNSUBSCRIBE and more, see
>> https://stat.ethz.ch/mailman/listinfo/r-help
>> PLEASE do read the posting guide http://www.R-project.org/posti
>> ng-guide.html
>> and provide commented, minimal, self-contained, reproducible code.
>>
>>
> ______________________________________________
> R-help using r-project.org mailing list -- To UNSUBSCRIBE and more, see
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide http://www.R-project.org/posti
> ng-guide.html
> and provide commented, minimal, self-contained, reproducible code.
>

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