[R] difference along a vector

[Marc Schwartz]

On May 12, 2010, at 2:06 PM, Clark Johnston wrote:

> 
> I was looking for  a function which would take the difference along a vector?
>> a<-c(1,12,23,44,15,28,7,8,9,10)
> if I set the number difference to 3 would return
> 43
> 2
> 5
> -37
> -7
> -19
> 3
> 
> or do I need to write my own function for this.

?diff

> diff(a, lag = 3)
[1]  43   3   5 -37  -7 -19   3

HTH,

Marc Schwartz