sums: Form Row and Column Sums and Means

In slam: Sparse Lightweight Arrays and Matrices

Description

Form row and column sums and means for sparse arrays (currently simple_triplet_matrix only).

Usage

row_sums(x, na.rm = FALSE, dims = 1, ...)
col_sums(x, na.rm = FALSE, dims = 1, ...)
row_means(x, na.rm = FALSE, dims = 1, ...)
col_means(x, na.rm = FALSE, dims = 1, ...)

## S3 method for class 'simple_triplet_matrix'
row_sums(x, na.rm = FALSE, dims = 1, ...)
## S3 method for class 'simple_triplet_matrix'
col_sums(x, na.rm = FALSE, dims = 1, ...)
## S3 method for class 'simple_triplet_matrix'
row_means(x, na.rm = FALSE, dims = 1, ...)
## S3 method for class 'simple_triplet_matrix'
col_means(x, na.rm = FALSE, dims = 1, ...)

Arguments

x	a sparse array containing numeric, integer, or logical values.
na.rm	logical. Should missing values (including NaN) be omitted from the calculations?
dims	currently not used for sparse arrays.
...	currently not used for sparse arrays.

Details

Provides fast summation over the rows or columns of sparse matrices in simple_triplet-form.

Value

A numeric (double) array of suitable size, or a vector if the result is one-dimensional. The dimnames (or names for a vector result) are taken from the original array.

Note

Results are always of storage type double to avoid (integer) overflows.

Author(s)

Christian Buchta

See Also

simple_triplet_matrix, colSums for dense numeric arrays.

Examples

##
x <- matrix(c(1, 0, 0, 2, 1, NA), nrow = 3)
x
s <- as.simple_triplet_matrix(x)
row_sums(s)
row_sums(s, na.rm = TRUE)
col_sums(s)
col_sums(s, na.rm = TRUE)

Example output

     [,1] [,2]
[1,]    1    2
[2,]    0    1
[3,]    0   NA
[1]  3  1 NA
[1] 3 1 0
[1]  1 NA
[1] 1 3

slam documentation built on Jan. 8, 2022, 5:08 p.m.