function a = integration ( alpha, n ) %*****************************************************************************80 % %% INTEGRATION returns the integration matrix. % % Formula: % % if ( I = J ) % A(I,J) = 1 % else if ( J = I + 1 ) % A(I,J) = ALPHA / I % else % A(I,J) = 0 % % Example: % % ALPHA = 2, N = 5 % % 1 2 0 0 0 % 0 1 2/2 0 0 % 0 0 1 2/3 0 % 0 0 0 1 2/4 % 0 0 0 0 1 % % Properties: % % A is generally not symmetric: A' /= A. % % A is unit upper triangular. % % A is bidiagonal. % % Because A is bidiagonal, it has property A (bipartite). % % A is nonsingular. % % det ( A ) = 1. % % A is unimodular. % % LAMBDA(1:N) = 1. % % Licensing: % % This code is distributed under the GNU LGPL license. % % Modified: % % 12 October 2007 % % Author: % % John Burkardt % % Parameters: % % Input, real ALPHA, the scalar which defines the first % superdiagonal of the matrix. % % Input, integer N, the number of rows and columns of A. % % Output, real A(N,N), the matrix. % for i = 1 : n for j = 1 : n if ( j == i ) a(i,j) = 1.0; elseif ( j == i + 1 ) a(i,j) = alpha / i; else a(i,j) = 0.0; end end end return end