colStats {matter} | R Documentation

## Row and Column Summary Statistics

### Description

These functions perform calculation of summary statistics over matrix rows and columns, for each level of a grouping variable (optionally), and with implicit row/column scaling and centering if desired.

### Usage

    ## S4 method for signature 'ANY'
    colStats(x, stat, groups,
        na.rm = FALSE, tform = identity,
        col.center = NULL, col.scale = NULL,
        row.center = NULL, row.scale = NULL,
        drop = TRUE, BPPARAM = bpparam(), ...)

    ## S4 method for signature 'ANY'
    rowStats(x, stat, groups,
        na.rm = FALSE, tform = identity,
        col.center = NULL, col.scale = NULL,
        row.center = NULL, row.scale = NULL,
        drop = TRUE, BPPARAM = bpparam(), ...)

### Arguments

`x` | A matrix on which to calculate summary statistics.
`stat` | The name of summary statistics to compute over the rows or columns of a matrix. Allowable values include: "min", "max", "prod", "sum", "mean", "var", "sd", "any", "all", and "nnzero".
`groups` | A factor or vector giving the grouping. If not provided, no grouping will be used.
`na.rm` | If `TRUE`, remove `NA` values before summarizing.
`tform` | A dimensionality-preserving transformation to be applied to the matrix (e.g., `log()` or `sqrt()`).
`col.center` | A vector of column centers to substract from each row. (Or a matrix with a column for each level of `groups`.)
`col.scale` | A vector of column scaling factors to divide from each row. (Or a matrix with a column for each level of `groups`.)
`row.center` | A vector of row centers to substract from each column. (Or a matrix with a column for each level of `groups`.)
`row.scale` | A vector of row centers to scaling factors to divide from each column. (Or a matrix with a column for each level of `groups`.)
`drop` | If only a single summary statistic is calculated, return the results as a vector (or matrix) rather than a list.
`BPPARAM` | An optional instance of `BiocParallelParam`. See documentation for `bplapply`.
`...` | Additional arguments.

### Details

The summary statistics methods are calculated over chunks of the matrix using `colstreamStats` and `rowstreamStats`. For `matter` objects, the iteration is performed over the major dimension for IO efficiency.

### Value

A list for each `stat` requested, where each element is either a vector (if no grouping variable is provided) or a matrix where each column corresponds to a different level of `groups`.

If `drop=TRUE`, and only a single statistic is requested, then the result will be unlisted and returned as a vector or matrix.

### Author(s)

Kylie A. Bemis

### See Also

`colSums`

### Examples

    register(SerialParam())

    set.seed(1)

    x <- matrix(runif(100^2), nrow=100, ncol=100)

    groups <- as.factor(rep(letters[1:5], each=20))

    colStats(x, "mean", groups=groups)

[Package matter version 1.18.0 Index]