colWeightedMads {DelayedMatrixStats} | R Documentation

## Weighted Median Absolute Deviation (MAD)

### Description

Computes a weighted MAD of a numeric vector.

### Usage

    colWeightedMads(x, w = NULL, rows = NULL, cols = NULL, na.rm = FALSE,
      constant = 1.4826, center = NULL, ...)

    rowWeightedMads(x, w = NULL, rows = NULL, cols = NULL, na.rm = FALSE,
      constant = 1.4826, center = NULL, ...)

    ## S4 method for signature 'DelayedMatrix'
    colWeightedMads(x, w = NULL, rows = NULL,
      cols = NULL, na.rm = FALSE, constant = 1.4826, center = NULL,
      force_block_processing = FALSE, ...)

    ## S4 method for signature 'DelayedMatrix'
    rowWeightedMads(x, w = NULL, rows = NULL,
      cols = NULL, na.rm = FALSE, constant = 1.4826, center = NULL,
      force_block_processing = FALSE, ...)

### Arguments

`x` | A NxK DelayedMatrix.
`w` | a vector of weights the same length as `x` giving the weights to use for each element of `x`. Negative weights are treated as zero weights. Default value is equal weight to all values.
`rows` | A `vector` indicating subset of elements (or rows and/or columns) to operate over. If `NULL`, no subsetting is done.
`cols` | A `vector` indicating subset of elements (or rows and/or columns) to operate over. If `NULL`, no subsetting is done.
`na.rm` | a logical value indicating whether `NA` values in `x` should be stripped before the computation proceeds, or not. If `NA`, no check at all for `NA`s is done. Default value is `NA` (for efficiency).
`constant` | A `numeric` scale factor, cf. `mad`.
`center` | Optional `numeric` scalar specifying the center location of the data. If `NULL`, it is estimated from data.
`...` | Additional arguments passed to specific methods.
`force_block_processing` | `FALSE` (the default) means that a seed-aware, optimised method is used (if available). This can be overridden to use the general block-processing strategy by setting this to `TRUE` (typically not advised). The block-processing strategy loads one or more (depending on `getOption("DelayedArray.block.size")`) columns (`colFoo()`) or rows (`rowFoo()`) into memory as an ordinary base::array.

### Value

Returns a `numeric` scalar.

### Missing values

Missing values are dropped at the very beginning, if argument `na.rm` is `TRUE`, otherwise not.

### See Also

For the non-weighted MAD, see `mad`. Internally `weightedMedian`() is used to calculate the weighted median.

### Examples

    # A DelayedMatrix with a 'matrix' seed
    dm_matrix <- DelayedArray(matrix(c(rep(1L, 5),
                                       as.integer((0:4) ^ 2),
                                       seq(-5L, -1L, 1L)),
                                     ncol = 3))

    colWeightedMads(dm_matrix, w = 1:5)

    rowWeightedMads(dm_matrix, w = 3:1)

[Package DelayedMatrixStats version 1.0.3 Index]