simple question on data frames assignment

== is also vectorised, and you're better off with TRUE and FALSE
rather than 1 and 0, so I'd recommend:

colordata$response <- colordata$color == 'blue'

Hadley

On Thu, Apr 7, 2016 at 6:52 AM, David Barron <dnbarron at gmail.com> wrote:

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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