matrixStats: rowCounts – R documentation

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rowCounts

Counts the number of occurrences of a specific value

Description

The row- and column-wise functions take either a matrix or a vector as input. If a vector, then argument dim. must be specified and fulfill prod(dim.) == length(x). The result will be identical to the results obtained when passing matrix(x, nrow = dim.[1L], ncol = dim.[2L]), but avoids having to temporarily create/allocate a matrix, if only such is needed only for these calculations.

Usage

rowCounts(x, rows = NULL, cols = NULL, value = TRUE, na.rm = FALSE,
  dim. = dim(x), ...)

colCounts(x, rows = NULL, cols = NULL, value = TRUE, na.rm = FALSE,
  dim. = dim(x), ...)

count(x, idxs = NULL, value = TRUE, na.rm = FALSE, ...)

Arguments

`x`	An NxK `matrix` or an N * K `vector`.
`value`	A value to search for.
`na.rm`	If `TRUE`, `NA`s are excluded first, otherwise not.
`dim.`	An `integer` `vector` of length two specifying the dimension of `x`, also when not a `matrix`.
`...`	Not used.
`idxs, rows, cols`	A `vector` indicating subset of elements (or rows and/or columns) to operate over. If `NULL`, no subsetting is done.

Value

rowCounts() (colCounts()) returns an integer vector of length N (K). count() returns a scalar of type integer if the count is less than 2^31-1 (= .Machine$integer.max) otherwise a scalar of type double.

Author(s)

Henrik Bengtsson

Examples

x <- matrix(0:11, nrow = 4, ncol = 3)
x[2:3, 2:3] <- 2:5
x[3, 3] <- NA_integer_
print(x)

print(rowCounts(x, value = 2))
## [1]  0  1 NA  0
print(colCounts(x, value = 2))
## [1]  1  1 NA
print(colCounts(x, value = NA_integer_))
## [1] 0 0 1

print(rowCounts(x, value = 2, na.rm = TRUE))
## [1] 0 1 1 0
print(colCounts(x, value = 2, na.rm = TRUE))
## [1] 1 1 0

print(rowAnys(x, value = 2))
## [1] FALSE  TRUE  TRUE FALSE
print(rowAnys(x, value = NA_integer_))
## [1] FALSE FALSE  TRUE FALSE

print(colAnys(x, value = 2))
## [1] TRUE TRUE   NA
print(colAnys(x, value = 2, na.rm = TRUE))
## [1]  TRUE  TRUE FALSE

print(colAlls(x, value = 2))
## [1] FALSE FALSE FALSE

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