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clc, clf, clear all, close all;

f = input('Define function: ');

tol = input('Enter tolerance: ');

L = -100;

U = 100;

n=100;

j = 1;

for i = L:U

   if f(i)*f(i+1) < 0

       a(j) = i;

       b(j) = i+1;

       j = j+1;

   end

end

if ~exist('a', 'var')

   fprintf('Cannot solve using Bisection or False Position Method!');

   return;

end

choice = input('Select 1 for Bisection Method, 2 for False Position Method: ');

if choice == 1

   fprintf('------------------------------\n');

   fprintf('Solving using Bisection Method\n');

   fprintf('------------------------------\n');

elseif choice == 2

   fprintf('-----------------------------------\n');

   fprintf('Solving using False Position Method\n');

   fprintf('-----------------------------------\n');

else

   fprintf('Invalid Selection!\n');

   return;

end

x = a(1):0.001:b(end);

hold on, grid on, box on

set(gca,'fontname','times new roman','fontsize', 12)

set(gcf,'Position', [400 200 550 300])

xline(0), yline(0)

plot(x, f(x), 'b', 'linewidth', 1.5), xlabel('x'), ylabel('f(x)'),

for i = 1:length(a)

   c=0;

   fprintf('Guess %d: a=%d, b=%d\n', i, a(i),b(i));

   for j= 1:n

      cp = c;

      if choice == 1

          c = (a(i)+b(i))/2;

      else

          c = (a(i)*f(b(i))-b(i)*f(a(i)))/(f(b(i))-f(a(i)));

      end

      error = abs(c-cp);

      I(j,1)=j;

      A(j,1)=a(i);

      B(j,1)=b(i);

      fa(j,1)=f(a(i));

      fb(j,1)=f(b(i));

      C(j,1)=c;

      fc(j,1)=f(c);

      Error(j,1)=error;

      if error <= tol

          break

      end

      if f(a(i))*f(c) < 0

          b(i) = c;

      elseif f(a(i))*f(c) > 0

          a(i) = c;

      else

          break

      end

   end

   root(i)=c;

   data = table(I,A,B,fa,fb,C,fc,Error);

   disp(data)

   fprintf('Root is: %d\n', c);

   plot(c, 0, 'r*', 'LineWidth', 2)

   clear I A B fa fb C fc Error;

end