clear;
    clc;
    close all;

    % u,,xx=-(f/ea) on [0,L]
    % u,x(L)= R
    % u(0)=0

    % Parameters
    L= 1;
    % Parameters in force function
    A= .0001;
    E= 70e9;
    R= 1000;
    a= 1000;
    g= R/E*A;
    f= @(x) ((((-1)*(a)*(x))/E*A));

    % solve analytical solution

    u1 = dsolve(['D2y = ' char(sym(f))], ['Dy(1) = ' num2str(g)], ['y(0) ='
    num2str(0)] ,'x');


    % change symbolic function to anonymous matlab function for easier
    computing

    u = matlabFunction(u1);

    % plot the analytical solution
    n= 20;
    x = linspace(0, 1, n);
    plot(x, u(x), '-ro', 'LineWidth', 4)
    title('Analytical Solution u')
    axis([0, 1, 0, 3])
    xlabel('x')
    ylabel('u')