colCounts,dgCMatrix-method {sparseMatrixStats} | R Documentation

## Count how often an element in a row (column) of a matrix-like object is equal to a value

### Description

Count how often an element in a row (column) of a matrix-like object is equal to a value.

### Usage

    ## S4 method for signature 'dgCMatrix'
    colCounts(x, rows = NULL, cols = NULL, value = TRUE, na.rm = FALSE)

    ## S4 method for signature 'dgCMatrix'
    rowCounts(x, rows = NULL, cols = NULL, value = TRUE, na.rm = FALSE)

### Arguments

`x` | An NxK matrix-like object.
`rows` | A `vector` indicating the subset of rows (and/or columns) to operate over. If `NULL`, no subsetting is done.
`cols` | A `vector` indicating the subset of rows (and/or columns) to operate over. If `NULL`, no subsetting is done.
`value` | The value to search for.
`na.rm` | If `TRUE`, `NA`s are excluded first, otherwise not.

### Details

The S4 methods for `x` of type `matrix`, `array`, or `numeric` call `matrixStats::rowCounts` / `matrixStats::colCounts`.

### Value

Returns a `integer` `vector` of length N (K).

### See Also

- `matrixStats::rowCounts()` and `matrixStats::colCounts()` which are used when the input is a `matrix` or `numeric` vector.

- For checks if any element is equal to a value, see `rowAnys()`. To check if all elements are equal, see `rowAlls()`.

### Examples

    mat <- matrix(rnorm(15), nrow = 5, ncol = 3)
      mat[2, 1] <- NA
      mat[3, 3] <- Inf
      mat[4, 1] <- 0

      print(mat)

      rowCounts(mat)
      colCounts(mat)

      rowCounts(mat, value = 0)
      colCounts(mat, value = Inf, na.rm = TRUE)

[Package sparseMatrixStats version 0.99.2 Index]