R/rowSDs.R

In eheinzen/Ethan: A bunch of functions written by Ethan Heinzen

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###      Filename: rowSDs.R
### Creation Date: Tuesday, 18 August 2015 11:30 AM CDT
### Last Modified: Wednesday, 12 July 2017 10:30 AM CDT
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#' rowSDs
#'
#' Find the standard deviation of rows; analagous to rowMeans.
#'
#' @param x a matrix or data frame, containing numeric, integer, or logical values.
#' @param na.rm logical. Should missing values be omitted from calculations?
#' @return A vector with length \code{nrow(x)} containing the standard deviation of each row of x.
#' @examples
#' myMatrix <- rbind(c(1,2,3,4,5), c(TRUE, FALSE, TRUE, TRUE, FALSE), c(0.3, 0.2, NA, 0.1, 0.1))
#' rownames(myMatrix) <- c("a", "b", "c")
#' rowSDs(myMatrix, na.rm = TRUE)
#' @export
rowSDs <- function (x, na.rm = FALSE)
{
  z <- apply(x, 1, stats::sd, na.rm = na.rm)
  names(z) <- rownames(x)
  return(z)
}