MATLAB: Error a>b = true when a=b

error matlabfaq

in a cycle while a>b. when i get a=b inside the cycle the program doesn't stop.. if i do while a<b doesn't stop too.. if i print the number they are equal(eg 0.005). can be an approximation problem?
         k=2;
         while (f(x_old,y_old)<f(aux_x,aux_y))
             aux_x = x_old - (1/k)*step_x;
             aux_y = y_old - (1/k)*step_y;
             k=k+1;
         end

Best Answer

Remember, that 0.005 and 0.0049999999999999 are displayed equally in the command window, but they are not exactly equal. Check this by a subtraction:
format short
a = 0.00499999999999
% >> 0.0050
a - 0.005
% >> -9.9998e-015
Related Question