#!/usr/bin/env python def wathen_order ( nx, ny ): #*****************************************************************************80 # ## WATHEN_ORDER returns the order of the WATHEN matrix. # # Discussion: # # N = 3 * 3 * 2 + 2 * 2 + 2 * 3 + 1 = 29 # # Licensing: # # This code is distributed under the GNU LGPL license. # # Modified: # # 31 August 2014 # # Author: # # John Burkardt # # Reference: # # Nicholas Higham, # Algorithm 694: A Collection of Test Matrices in MATLAB, # ACM Transactions on Mathematical Software, # Volume 17, Number 3, September 1991, pages 289-305. # # Andrew Wathen, # Realistic eigenvalue bounds for the Galerkin mass matrix, # IMA Journal of Numerical Analysis, # Volume 7, 1987, pages 449-457. # # Parameters: # # Input, integer NX, NY, values which determine the size of A. # # Output, integer N, the order of the matrix, # as determined by NX and NY. # n = 3 * nx * ny + 2 * nx + 2 * ny + 1 return n