R/others__is.singular.R

In feng-li/flutils: Feng Li's utility functions

#' Check if a square matrix is computational singular
#'
#' @param X squared matrix
#' @return TRUE/FALSE
#' @author Feng Li, Department of Statistics, Stockholm University, Sweden.
#' @note Created: Mon Jan 02 17:58:12 CET 2012;
#'       Current: Mon Jan 02 17:58:37 CET 2012.
#' @export
is.singular <- function(X, tol = .Machine$double.eps*1e3)
  {
      if(is.matrix(X))
      {
          rcond.out <- rcond(X)
      }
      else
      {
          rcond.out <- Matrix::rcond(X)
      }

    if(rcond.out < tol)
      {
        singular = TRUE
      }
    else
      {
        singular  = FALSE
      }
    return(singular)
  }