Gets an order statistic for each row (column) in a matrix

Gets an order statistic for each row (column) in a matrix.

rowOrderStats(x, rows = NULL, cols = NULL, which, dim. = dim(x), ...,
  useNames = TRUE)

colOrderStats(x, rows = NULL, cols = NULL, which, dim. = dim(x), ...,
  useNames = TRUE)

Arguments

x: An NxK matrix or, if dim. is specified, an N * K vector.
rows: A vector indicating subset of rows to operate over. If NULL, no subsetting is done.
cols: A vector indicating subset of columns to operate over. If NULL, no subsetting is done.
which: An integer index in [1,K] ([1,N]) indicating which order statistic to be returned.
dim.: An integer vector of length two specifying the dimension of x, also when not a matrix. Comment: The reason for this argument being named with a period at the end is purely technical (we get a run-time error if we try to name it dim).
...: Not used.
useNames: If TRUE (default), names attributes of the result are set, otherwise not.

Value

Returns a numeric vector of length N (K).

Details

The implementation of rowOrderStats() is optimized for both speed and memory. To avoid coercing to doubles (and hence memory allocation), there is a unique implementation for integer matrices.

Missing values

This method does not handle missing values, that is, the result corresponds to having na.rm = FALSE (if such an argument would be available).

Author