R help - Jun 2011 - Partial Matching

Let's say that I have a string and I want to know if a single word
is present in the string. I've written the following function to see if
the word "Geico" is mentioned in the string "Cheap Geico car
insurance".
However, it doesn't work, and I assume it has something to do with the any()
function. Do I need to use regular expressions? (I hope not)

main <- function(keyword){
       for( i in keyword ){
            n = strsplit(as.character(keyword), " ")
            print( n )
            if( any( n=="Geico" )){
                 print( "Yes" )
          }
     }
}

main("Cheap Geico car insurance")


I'm running R 2.13 on Ubuntu 10.10


Thanks,
Abraham

	[[alternative HTML version deleted]]

On Sat, Jun 4, 2011 at 6:44 PM, Abraham Mathew <abmathewks at gmail.com>
wrote:
> Let's say that I have a string and I want to know if a single word
> is present in the string. I've written the following function to see if
> the word "Geico" is mentioned in the string "Cheap Geico car
insurance".
> However, it doesn't work, and I assume it has something to do with the
any()
> function. Do I need to use regular expressions? (I hope not)
>
> main <- function(keyword){
> ? ? ? for( i in keyword ){
> ? ? ? ? ? ?n = strsplit(as.character(keyword), " ")
> ? ? ? ? ? ?print( n )
> ? ? ? ? ? ?if( any( n=="Geico" )){
> ? ? ? ? ? ? ? ? print( "Yes" )
> ? ? ? ? ?}
> ? ? }
> }
>
> main("Cheap Geico car insurance")
>
strsplit returns a one component list containing the vector of words
so you want to replace the relevant statement with:

n = strsplit(as.character(keyword), " ")[[1]]

however, regular expressions is shorter:
> x <- c("Cheap Geico car insurance", "Cheap Gorilla car
insurance", "A Geicor car")
> regexpr("\\bGeico\\b", x) > 0
[1]  TRUE FALSE FALSE

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