R: Calculates difference for each row (column) in a matrix

rowDiffs {matrixStats} | R Documentation

## Calculates difference for each row (column) in a matrix

### Description

Calculates difference for each row (column) in a matrix.

### Usage

    rowDiffs(x, rows = NULL, cols = NULL, lag = 1L, differences = 1L,
      dim. = dim(x), ...)

    colDiffs(x, rows = NULL, cols = NULL, lag = 1L, differences = 1L,
      dim. = dim(x), ...)

### Arguments

`x` | A `numeric` NxK `matrix`.
`rows, cols` | A `vector` indicating subset of rows (and/or columns) to operate over. If `NULL`, no subsetting is done.
`lag` | An `integer` specifying the lag.
`differences` | An `integer` specifying the order of difference.
`dim.` | An `integer` `vector` of length two specifying the dimension of `x`, also when not a `matrix`.
`...` | Not used.

### Value

Returns a `numeric` Nx(K-1) or (N-1)xK `matrix`.

### Author(s)

Henrik Bengtsson

### See Also

See also `diff2`().

### Examples

    x <- matrix(1:27, ncol = 3)

    d1 <- rowDiffs(x)
    print(d1)

    d2 <- t(colDiffs(t(x)))
    stopifnot(all.equal(d2, d1))

[Package matrixStats version 0.55.0 Index]