R help - May 2012 - Matching - finding and listing data that is one object but not in another

What is the best way to find out what elements/numbers that are in one
object are not in another.


I came up with this method, but I'm wondering if there is a more efficient
way (and one that doesn't seem so "clunky").

#Example

id <- c(1,2,3,4,5,6,7,9,10)

example.1 <- data.frame(id)

#Second object, this time with an 8 in it.

id <- c(1,2,3,4,5,6,7,8,9,10)

example.2 <- data.frame(id)

finder <- example.2$id %in% example.1$id

example.2 <- cbind(example.2,finder)

missing.list <- subset(example.2, test2==F)

	[[alternative HTML version deleted]]

? setdiff

Michael

On May 11, 2012, at 8:50 AM, James Holland <holland.aggie at gmail.com>
wrote:
> What is the best way to find out what elements/numbers that are in one
> object are not in another.
> 
> 
> I came up with this method, but I'm wondering if there is a more
efficient
> way (and one that doesn't seem so "clunky").
> 
> #Example
> 
> id <- c(1,2,3,4,5,6,7,9,10)
> 
> example.1 <- data.frame(id)
> 
> #Second object, this time with an 8 in it.
> 
> id <- c(1,2,3,4,5,6,7,8,9,10)
> 
> example.2 <- data.frame(id)
> 
> finder <- example.2$id %in% example.1$id
> 
> example.2 <- cbind(example.2,finder)
> 
> missing.list <- subset(example.2, test2==F)
> 
>    [[alternative HTML version deleted]]
> 
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