[R] simple question on data frames assignment

[David Barron]

ifelse is vectorised, so just use that without the loop.

colordata$response <- ifelse(colordata$color == 'blue', 1, 0)

David

On 7 April 2016 at 12:41, Michael Artz <michaeleartz at gmail.com> wrote:

> Hi I'm not sure how to ask this, but its a very easy question to answer for
> an R person.
>
> What is an easy way to check for a column value and then assigne a new
> column a value based on that old column value?
>
> For example, Im doing
>  colordata <- data.frame(id = c(1,2,3,4,5), color = c("blue", "red",
> "green", "blue", "orange"))
>  for (i in 1:nrow(colordata)){
>    colordata$response[i] <- ifelse(colordata[i,"color"] == "blue", 1, 0)
>  }
>
> which works,  but I don't want to use the for loop I want to "vecotrize"
> this.  How would this be implemented?
>
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>
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