Aggregate function: returns the last value in a group.
Usage
last(x, ...)
# S4 method for characterOrColumn
last(x, na.rm = FALSE)
Arguments
x
column to compute on.
...
further arguments to be passed to or from other methods.
na.rm
a logical value indicating whether NA values should be stripped
before the computation proceeds.
Details
The function by default returns the last values it sees. It will return the last non-missing
value it sees when na.rm is set to true. If all values are missing, then NA is returned.
Note: the function is non-deterministic because its results depends on order of rows which
may be non-deterministic after a shuffle.