matrixStats: x_OP_y – R documentation

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x_OP_y

Fast calculation of 'z <- x OP y' and 'z <- t(t(x) OP y)'

Description

Fast calculation of 'z <- x OP y' and 'z <- t(t(x) OP y)', where OP can be +, -, *, and /. For + and *, na.rm = TRUE will drop missing values first.

Usage

x_OP_y(x, y, OP, xrows = NULL, xcols = NULL, yidxs = NULL,
  commute = FALSE, na.rm = FALSE)

t_tx_OP_y(x, y, OP, xrows = NULL, xcols = NULL, yidxs = NULL,
  commute = FALSE, na.rm = FALSE)

Arguments

`x`	A `numeric` or `logical` NxK `matrix`.
`y`	A `numeric` or `logical` `vector` of length L.
`OP`	A `character` specifying which operator to use.
`xrows, xcols`	A `vector` indicating subset of rows (and/or columns) to operate over 'x'. If `NULL`, no subsetting is done.
`commute`	If `TRUE`, 'y OP x' ('t(y OP t(x))') is calculated, otherwise 'x OP y' ('t(t(x) OP y)').
`na.rm`	If `TRUE`, missing values are ignored, otherwise not.
`idxs`	A `vector` indicating subset of elements to operate over 'y'. If `NULL`, no subsetting is done.
`...`	Not used.

Value

Returns a numeric NxK matrix.

Missing values

If na.rm = TRUE, then missing values are "dropped" before applying the operator to each pair of values. For instance, if x[1, 1] is a missing value, then the result of x[1, 1] + y[1] equals y[1]. If also y[1] is a missing value, then the result is a missing value. This only applies to additions and multiplications. For subtractions and divisions, argument na.rm is ignored.

Author(s)

Henrik Bengtsson

Examples

x <- matrix(c(1, 2, 3, NA, 5, 6), nrow = 3, ncol = 2)

# Add 'y' to each column
y <- 1:2
z0 <- x + y
z1 <- x_OP_y(x, y, OP = "+")
print(z1)
stopifnot(all.equal(z1, z0))


# Add 'y' to each row
y <- 1:3
z0 <- t(t(x) + y)
z1 <- t_tx_OP_y(x, y, OP = "+")
print(z1)
stopifnot(all.equal(z1, z0))

matrixStats

Functions that Apply to Rows and Columns of Matrices (and to Vectors)

v0.58.0

Artistic-2.0

Authors

Henrik Bengtsson [aut, cre, cph], Constantin Ahlmann-Eltze [ctb], Hector Corrada Bravo [ctb], Robert Gentleman [ctb], Jan Gleixner [ctb], Peter Hickey [ctb], Ola Hossjer [ctb], Harris Jaffee [ctb], Dongcan Jiang [ctb], Peter Langfelder [ctb], Brian Montgomery [ctb], Hugh Parsonage [ctb]

Initial release