[R] error in IF condition with factor evaluation

[Eik Vettorazzi]

Hi Edoardo,
there is a difference between comparisons and assignments, both
semantically as well as in R syntax: "==" vs "=" or "<-", latter being
more obvious an assignment.
This is the source of your error.
But to change the labels of a factor object, it is easier to do sth like

at<-factor(1:5,labels=letters[1:5])
at
levels(at)[3]<-"xyz"
at   #check

hth



Am 23.11.2012 10:42, schrieb edoardo baldoni:
> Cam anyone tell me why the condition x[i] == "DISCONECTED" looks like
> producing an NA instead of TRUE/FALSE
> 
> I would like to rename "DISCONNECTED" those factors inside the variable
> "dataset$STATUS.x" that are named "DISCONECTED"
> 
> thank you
> 
> 
>> summary(dataset$STATUS.x)
>      ACTIVE DISCONECTED     PENDING   SUSPENDED  TERMINATED
>      158869      169181        3028        8565       47233
>        NA's
>           6
>> class(dataset$STATUS.x)
> [1] "factor"
>>
>> fff = function(x) {
> + for (i in 1:length(x)){
> + if (x[i] == "DISCONECTED") {
> + x[i] == "DISCONNECTED"
> + } else x[i] == x[i]
> + }
> + return(x)
> + }
>>
>> r = fff(dataset$STATUS.x)
> Error in if (x[i] == "DISCONECTED") { :
>   missing value where TRUE/FALSE needed
> 
> 	[[alternative HTML version deleted]]
> 
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Eik Vettorazzi
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