# S3 method for default
diff(x, lag = 1, differences = 1, …)
# S3 method for POSIXt
diff(x, lag = 1, differences = 1, …)
# S3 method for Date
diff(x, lag = 1, differences = 1, …)
Arguments
x
a numeric vector or matrix containing the values to be
differenced.
lag
an integer indicating which lag to use.
differences
an integer indicating the order of the difference.
…
further arguments to be passed to or from methods.
Value
If x is a vector of length n and differences = 1,
then the computed result is equal to the successive differences
x[(1+lag):n] - x[1:(n-lag)]. If difference is larger than one this algorithm is applied
recursively to x.
Note that the returned value is a vector which is shorter than
x. If x is a matrix then the difference operations are carried out
on each column separately.
Details
diff is a generic function with a default method and ones for
classes "ts", "POSIXt" and
"Date". NA's propagate.
References
Becker, R. A., Chambers, J. M. and Wilks, A. R. (1988)
The New S Language.
Wadsworth & Brooks/Cole.