Matlab - Error using mupadmex Error in MuPAD command: DOUBLE cannot convert the input expression into a doubl

Hola, soy nuevo en esto y tengo el siguiente error
Error using mupadmex
Error in MuPAD command: DOUBLE cannot convert the input expression into a double array.

If the input expression contains a symbolic variable, use the VPA function instead.

Error in sym/double (line 936)
Xstr = mupadmex('symobj::double', S.s, 0);

Error in sym>privformatscalar (line 2707)
x = double(x);

Error in sym>privformat (line 2692)
s = privformatscalar(x);

Error in sym/subsasgn (line 1462)
[inds{k},refs{k}] = privformat(inds{k});

Error in aitken (line 3)
f(x) = (1/2)*(x + 2/x) ; %The function that find the next element in the sequence

Mi código es para el método delta cuadrado de Aitken, y es el siguiente

Que debo hacer para que funcione??

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% Mi código es para el método delta cuadrado de Aitken, y es el siguiente

 %These choices depend on the problem being solved

 clc

 clear all

 syms x

 x0=1; %The initial value

 f(x) = (1/2)*(x + 2/x) ; %The function that find the next element in the sequence

 tolerance = 10^-10 ; %10 digit accuracy is desired

 epsilon = 10^-16 ; %Don't want to divide by a number smaller than this

 maxIterations = 20 ; %Don't allow the iterations to continue indefinitely

 haveWeFoundSolution = false;%Were we able to find the solution to the desired tolerance? not yet.

 for i = 1 : maxIterations

 x1 = f(x0);

 x2 = f(x1);

 lambda = abs((x2 - x1)/(x1 - x0)); %OPTIONAL: computes an approximation of |f'(fixedPoint)|, which is denoted by lambda

 denominator = x2 - 2*x1 + x0;

 if(abs(denominator) < epsilon) %Don't want to divide by too small of a number

 print('WARNING: denominator is too small')

 break; %Leave the loop

 end

 aitkenX = x2 - ( (x2 - x1)^2 )/(denominator);

 if(abs(aitkenX - x2) < tolerance) %If the result is within tolerance

 fprintf('The fixed point is %f', double(aitkenX)) %Display the result of the Aitken extrapolation

 haveWeFoundSolution = true;

 break; %Done, so leave the loop

 end

 x0 = aitkenX; %Update x0 to start again 

 end

 if(haveWeFoundSolution == false) %If we weren't able to find a solution to within the desired tolerance

 print('Warning: Not able to find solution to within the desired tolerance of ', tolerance);

 print('"The last computed extrapolate was ', aitkenX)

 end

ejecución

1

The fixed point is 1.414214>>

Saludos
JOSE JEREMÍAS CABALLERO
Asesoría online en Matlab
Servicios de programación matlab
[email protected]
Estimado Usuario, el correo es para servicios de cursos, asesorías y programación. Toda ayuda gratuita es vía foro

http://matlabcaballero.blogspot.com

hola José, te cuento que copié y pegue lo mismo que tu me mandaste y al ejecutar me aparece esto, mi version de matlab puede influir? es la r2011b.

Error using mupadmex
Error in MuPAD command: DOUBLE cannot convert the input expression into a double array.

If the input expression contains a symbolic variable, use the VPA function instead.

Error in sym/double (line 936)
Xstr = mupadmex('symobj::double', S.s, 0);

Error in sym>privformatscalar (line 2707)
x = double(x);

Error in sym>privformat (line 2692)
s = privformatscalar(x);

Error in sym/subsasgn (line 1462)
[inds{k},refs{k}] = privformat(inds{k});

Error in Untitled3 (line 11)
f(x) = (1/2)*(x + 2/x) ; %The function that find the next element in the sequence

AQUI NUEVAMENTE EL CODIGO

%These choices depend on the problem being solved

clc

clear all

syms x

x0=1; %The initial value

f(x) = (1/2)*(x + 2/x) ; %The function that find the next element in the sequence

tolerance = 10^-10 ; %10 digit accuracy is desired

epsilon = 10^-16 ; %Don't want to divide by a number smaller than this


maxIterations = 20 ; %Don't allow the iterations to continue indefinitely

haveWeFoundSolution = false;%Were we able to find the solution to the desired tolerance? not yet.



for i = 1 : maxIterations

x1 = f(x0);

x2 = f(x1);



lambda = abs((x2 - x1)/(x1 - x0)); %OPTIONAL: computes an approximation of |f'(fixedPoint)|, which is denoted by lambda


denominator = x2 - 2*x1 + x0;


if(abs(denominator) < epsilon) %Don't want to divide by too small of a number

print('WARNING: denominator is too small')

break; %Leave the loop

end



aitkenX = x2 - ( (x2 - x1)^2 )/(denominator);



if(abs(aitkenX - x2) < tolerance) %If the result is within tolerance

fprintf('The fixed point is %f', double(aitkenX)) %Display the result of the Aitken extrapolation

haveWeFoundSolution = true;

break; %Done, so leave the loop

end





x0 = aitkenX; %Update x0 to start again



end



if(haveWeFoundSolution == false) %If we weren't able to find a solution to within the desired tolerance

print('Warning: Not able to find solution to within the desired tolerance of ', tolerance);

print('"The last computed extrapolate was ', aitkenX)

end

??? no entiendo a lo que te refieres.....

revisa el código que te mando, te estoy diciendo que modifiques ese línea ya que tu matlab no soporta la instrucción f(x). Tienes que leer los códigos y no es solo pegar.
saludos.