why my iteration prog doesn't work ?
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khalid boureeny
el 23 de En. de 2017
Comentada: Walter Roberson
el 25 de En. de 2017
% Use NR method f(x)= x^3-5x^2+7x-3
clc
TV=3;
x=(4);
tol=0.0007;
format long
for i=1:5;
fx=(x(i))^3-5*(x(i))^2+7*(x(i))-3;
fxx=3*(x(i))^2-10*(x(i))+7;
x(i+1)=(x(i))-(fx/fxx);
E_T(i)=(abs((TV-x(i+1))/TV))*100;
end
for i=1:5;
e(i)=(x(6))-(x(i));
fx=(x(i))^3-5*(x(i))^2+7*(x(i))-3;
fxx=3*(x(i))^2-10*(x(i))+7;
fxxx=6*(x(i))-10;
e(i+1)=(-fxxx/2*fxx)*(e(i))^2;
end
if abs(TV-(x(i+1)))<tol
disp(' enough to here')
disp(' -----------')
disp(' x(i+1) ')
disp(' -----------')
x;
disp(' -----------')
disp(' T.V ')
disp(' -----------')
E_T;
disp(' -----------')
disp(' E(i+1) ')
disp(' -----------')
e;
disp(' ------------- ')
end
%-----------------------------------------------------------
7 comentarios
khalid boureeny
el 25 de En. de 2017
Editada: Walter Roberson
el 25 de En. de 2017
Walter Roberson
el 25 de En. de 2017
If you need 50 or 80 digits you will need to switch to the Symbolic Toolbox, and display using vpa()
NumDig = 50;
x = sym(-0.1);
y = sym(0);
fprintf(' i x \n')
fprintf(' --- ------------- \n')
for i=1:5;
fx=(x(i))^3-(x(i))^2+2;
fxx=3*(x(i))^2-2*(x(i));
y(i)=x(i)-(fx/fxx);
fy=(y(i))^3-(y(i))^2+2;
fyy=3*(y(i))^2-2*(y(i));
x(i+1)=x(i)+([fy-fx]/fyy);
end
for i=1:length(x)
fprintf('%2i %s\n', i, char(vpa(x(i),NumDig)))
end
Respuesta aceptada
Walter Roberson
el 23 de En. de 2017
In your section
if abs(TV-(x(i+1)))<tol
disp(' enough to here')
disp(' -----------')
disp(' x(i+1) ')
disp(' -----------')
x;
disp(' -----------')
disp(' T.V ')
disp(' -----------')
E_T;
disp(' -----------')
disp(' E(i+1) ')
disp(' -----------')
e;
disp(' ------------- ')
end
remove the ';' from the 'x;' and 'E_T;' and 'e;' -- so
if abs(TV-(x(i+1)))<tol
disp(' enough to here')
disp(' -----------')
disp(' x(i+1) ')
disp(' -----------')
x
disp(' -----------')
disp(' T.V ')
disp(' -----------')
E_T
disp(' -----------')
disp(' E(i+1) ')
disp(' -----------')
e
disp(' ------------- ')
end
2 comentarios
Más respuestas (1)
Lateef Adewale Kareem
el 23 de En. de 2017
increase your number of iteration, you will meet the tolerance target
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