Calculates the sum for each row (column) in a matrix.
rowSums2(x, rows = NULL, cols = NULL, na.rm = FALSE, dim. = dim(x),
..., useNames = TRUE)colSums2(x, rows = NULL, cols = NULL, na.rm = FALSE, dim. = dim(x),
..., useNames = TRUE)
Returns a numeric
vector
of
length N (K).
A vector
indicating subset of rows to
operate over. If NULL
, no subsetting is done.
A vector
indicating subset of columns to
operate over. If NULL
, no subsetting is done.
If TRUE
, missing values are
excluded.
An integer
vector
of
length two specifying the dimension of x
, also when not a
matrix
. Comment: The reason for this argument
being named with a period at the end is purely technical (we get a run-time
error if we try to name it dim
).
Not used.
If FALSE
(default), no naming
support is done. Else if TRUE
, names attributes
of result are set.
Henrik Bengtsson
The implementation of rowSums2()
and colSums2()
is
optimized for both speed and memory.