I have a problem with integration "Error using / Matrix dimensions must agree"
1 vue (au cours des 30 derniers jours)
Afficher commentaires plus anciens
syntax is here:
clc;clear all;close all;
m=input('input a value');
x=linspace(1,2,m);
%function
f=(x+(1/x)).^2;
%real value of integral
ff=@(x)(x+(1/x)).^2;
RV=integral(ff,1,2);
%Solution with numerical method (Trap method)
IT=Trap(x,f,m)
ybh=100*(abs(RV-IT)/RV
function IT=Trap(x,f,m)
IT=(x(m)-x(1))*(f(1)+f(m))/2
return
end
Why this isnt working?
ERROR:
input a value2
Error using /
Matrix dimensions must agree.
Error in odev (line 5)
f=(x+(1/x)).^2;
Thank you.
0 commentaires
Réponse acceptée
Fabio Freschi
le 6 Nov 2019
When you define your functions use ./ instead of /
%function
f=(x+(1./x)).^2;
%real value of integral
ff=@(x)(x+(1./x)).^2;
6 commentaires
Fabio Freschi
le 7 Nov 2019
Maybe I got the point: your code does not exit with an error, but it produces the wrong result!
Your implementation of the trapezoidal rule is not correct. You are not using all your samples but only the first and last points. If you really don't want to use the built-in trapz, you can implement yourself as
Itrap = sum((f(2:end)+f(1:end-1)).*(x(2:end)-x(1:end-1))/2)
Plus de réponses (0)
Voir également
Catégories
En savoir plus sur Numerical Integration and Differentiation dans Help Center et File Exchange
Produits
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!