cmna: Computational Methods for Numerical Analysis

## Copyright (c) 2016, James P. Howard, II <jh@jameshoward.us>
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#' @title Himmelblau Function
#'
#' @description
#' Generate the Himmelblau function
#'
#' @param x a vector of \code{x}-values
#'
#' @details
#' Generate the Himmelblau function
#'
#' @return the value of the function at \code{x}.
#'
#' @export
himmelblau <- function(x) {
  (x[1]^2 + x[2] - 11)^2 + (x[1] + x[2]^2 - 7)^2
}