| # File src/library/stats/R/mad.R |
| # Part of the R package, https://www.R-project.org |
| # |
| # Copyright (C) 1995-2012 The R Core Team |
| # |
| # This program is free software; you can redistribute it and/or modify |
| # it under the terms of the GNU General Public License as published by |
| # the Free Software Foundation; either version 2 of the License, or |
| # (at your option) any later version. |
| # |
| # This program is distributed in the hope that it will be useful, |
| # but WITHOUT ANY WARRANTY; without even the implied warranty of |
| # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| # GNU General Public License for more details. |
| # |
| # A copy of the GNU General Public License is available at |
| # https://www.R-project.org/Licenses/ |
| |
| mad <- function(x, center = median(x), constant = 1.4826, |
| na.rm = FALSE, low = FALSE, high = FALSE) |
| { |
| if(na.rm) |
| x <- x[!is.na(x)] |
| n <- length(x) |
| constant * |
| if((low || high) && n%%2 == 0) { |
| if(low && high) stop("'low' and 'high' cannot be both TRUE") |
| n2 <- n %/% 2 + as.integer(high) |
| sort(abs(x - center), partial = n2)[n2] |
| } |
| else median(abs(x - center)) |
| } |
| |