R help - Jul 2010 - Data Frame Manipulation using function

Hi all,

I have a data frame for which I want to limit the output by checking whether
row values for specific column meets particular conditions.

Here are the more specific details:

I have a function that checks whether an input string exists in a defined
list:-

checkBaseLine <- function(s){
 for (listItem in WHITELIST){
if(regexpr(as.character(listItem), s)[1] > -1){
 return(TRUE)
}
}
 return(FALSE)
}

Now, I have a data frame for which I want to apply the above function for
all row values for a given column:-

This works fine when I define a condition like:
data <- data[data$urlType != 1,]

However, I want to combine two logical conditions together like:
data <- data[data$urlType != 1 & checkBaseLine(data$url),]

This would check whether the column `urlType` contains row values that !1,
and the column `url` contains row values that gets evaluated using the
defined function.

Any ideas how this can be done?

Thanks in advance.

Regards,
Harsh Yadav

	[[alternative HTML version deleted]]

It will be a lot easier to help you if you follow the posting guide and PLEASE 
do read the posting guide and provide commented, minimal, self-contained, 
reproducible code.

You gave your function definition, which is good.  Use ?dput to give us a small 
data.frame that can accurately show what you want.


harsh yadav wrote:
> Hi all,
> 
> I have a data frame for which I want to limit the output by checking
whether
> row values for specific column meets particular conditions.
> 
> Here are the more specific details:
> 
> I have a function that checks whether an input string exists in a defined
> list:-
> 
> checkBaseLine <- function(s){
>  for (listItem in WHITELIST){
> if(regexpr(as.character(listItem), s)[1] > -1){
>  return(TRUE)
> }
> }
>  return(FALSE)
> }
> 
> Now, I have a data frame for which I want to apply the above function for
> all row values for a given column:-
> 
> This works fine when I define a condition like:
> data <- data[data$urlType != 1,]
> 
> However, I want to combine two logical conditions together like:
> data <- data[data$urlType != 1 & checkBaseLine(data$url),]
> 
> This would check whether the column `urlType` contains row values that
!> 1,
> and the column `url` contains row values that gets evaluated using the
> defined function.
> 
> Any ideas how this can be done?
> 
> Thanks in advance.
> 
> Regards,
> Harsh Yadav
> 
> 	[[alternative HTML version deleted]]
> 
> ______________________________________________
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> PLEASE do read the posting guide
http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.