function [ fxx, fxy, fyy ] = f08_f2 ( n, x, y ) %*****************************************************************************80 % %% F08_F2 returns second derivatives of function 8. % % Licensing: % % This code is distributed under the GNU LGPL license. % % Modified: % % 29 January 2012 % % Author: % % John Burkardt % % Parameters: % % Input, integer N, the number of evaluation points. % % Input, real X(N,1), Y(N,1), the evalution points. % % Output, real FXX(N,1), FXY(N,1), FYY(N,1), second derivatives. % t1(1:n,1) = 5.0 - 10.0 * x(1:n,1); t2(1:n,1) = 5.0 - 10.0 * y(1:n,1); t3(1:n,1) = exp ( - 0.5 * t1(1:n,1) .* t1(1:n,1) ); t4(1:n,1) = exp ( - 0.5 * t2(1:n,1) .* t2(1:n,1) ); fxx(1:n,1) = t3(1:n,1) .* ( t1(1:n,1) .* t1(1:n,1) - 1.0 ) .* ( 100.0 + 75.0 * t4(1:n,1) ); fxy(1:n,1) = 75.0 * t1(1:n,1) .* t2(1:n,1) .* t3(1:n,1) .* t4(1:n,1); fyy(1:n,1) = t4(1:n,1) .* ( t2(1:n,1) .* t2(1:n,1) - 1.0 ) .* ( 75.0 + 75.0 * t3(1:n,1) ); return end