function A = hilbert_inv ( n ) % % function A = hilbert_inv ( n ) % % HILBERT_INV returns the inverse of the Hilbert matrix. % % Modified: % % 14 February 2000 % % Author: % % John Burkardt % % Parameters: % % Input, integer N, the order of A. % % Output, real A(N,N), the inverse Hilbert matrix. % A = zeros ( n, n ); % % Set the (1,1) entry. % A(1,1) = n^2; % % Define Row 1, Column J by recursion on Row 1 Column J-1. % i = 1; for j = 2 : n A(i,j) = - A(i,j-1) * ( (n+j-1) * (i+j-2) * (n+1-j) ) ... / ( (i+j-1) * (j-1)^2 ); end % % Define Row I by recursion on row I-1. % for i = 2 : n for j = 1 : n A(i,j) = - A(i-1,j) * ( (n+i-1) * (i+j-2) * (n+1-i) ) ... / ( (i+j-1) * (i-1)^2 ); end end