Borrar filtros
Borrar filtros

How to determine how a loop finishes

3 visualizaciones (últimos 30 días)
Chris
Chris el 18 de Nov. de 2013
Respondida: Chris el 18 de Nov. de 2013
Alright, so I have an assignment where I am to use the secant method to find the root of a function. I have the program written for the most part, and I'm able to find the root of a function no problem. However, I don't know how to have an output that can determine whether the loop finished because an answer was found, or if all the iterations were used and an answer was not located. I think I'm supposed to use an if/end or if/else kind of statement, but I'm not completely sure. I have the code listed below, any help would be greatly appreciated.
syms x
func=('x^2 - 4');
A=0; % A= x(k-1)
B=10;% B= x(k)
abs_err=0.00001;
n=5; %number of iterations
f = inline(func);
C = B - ((B-A)/(f(B) - f(A)))*f(B); % C= x(k+1)
display([' The function to be used is ' func])
fprintf(' The first guess, x(1) is equal to %g\n',A)
fprintf(' The second guess, x(2) is equal to %g\n',B)
fprintf(' The absolute approximate error, Ea, is equal to %g\n',abs_err)
fprintf(' The maximum number of iterations to conduct, n, is equal to %g\n',n)
disp(' ')
while abs(f(C)) > abs_err
A=B;
B=C;
C= B - ((B-A)/(f(B) - f(A)))*f(B);
n=n+1;
if(n==1000)
break
end
end
disp('Outputs')
display([' The root of the function = ' num2str(C)])

Respuesta aceptada

Image Analyst
Image Analyst el 18 de Nov. de 2013
Editada: Image Analyst el 18 de Nov. de 2013
After the loop:
if n >= 1000
message = sprintf('No solution found after %d iterations.', n);
uiwait(warndlg(message));
else
message = sprintf(('Outputs\n The root of the function = %f\n', C);
uiwait(warndlg(message));
end

Más respuestas (1)

Chris
Chris el 18 de Nov. de 2013
Thank you very much, that helped a lot.

Categorías

Más información sobre Loops and Conditional Statements en Help Center y File Exchange.

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by