Effacer les filtres
Effacer les filtres

How can I fix this error?

3 vues (au cours des 30 derniers jours)
Wenchen Liu
Wenchen Liu le 5 Déc 2022
Commenté : Torsten le 5 Déc 2022
I had a code like this:
clear all, close all
f = @(x)(4/(1+x^2));
a = 0;
b = 1;
F = @(x)(-8x/((1+x^2)^2)); % antiderivative of f
ref = F(b) - F(a);
n = 2;
x = linspace(a,b,n+1);
h = (b-a)/n;
then in the command part, it shows:
File: assignment3_question2b.m Line: 7 Column: 12
Invalid expression. Check for missing multiplication operator, missing or unbalanced
delimiters, or other syntax error. To construct matrices, use brackets instead of parentheses.
How can i fix this?

Réponses (1)

David Hill
David Hill le 5 Déc 2022
f = @(x)4./(1+x.^2)
f = function_handle with value:
@(x)4./(1+x.^2)
a = 0;
b = 1;
F = @(x)-8*x./(1+x.^2).^2 % antiderivative of f
F = function_handle with value:
@(x)-8*x./(1+x.^2).^2
ref = F(b) - F(a);
n = 2;
x = linspace(a,b,n+1);
h = (b-a)/n;
  2 commentaires
Wenchen Liu
Wenchen Liu le 5 Déc 2022
clear all, close all
f = @(x)4./(1+x.^2);
a = 0;
b = 1;
F = @(x)-8*x.(1+x.^2).^2; % antiderivative of f
ref = F(b) - F(a);
n = 2;
x = linspace(a,b,n+1);
h = (b-a)/n;
i have fixed the questions, but in the command it still shows:
Argument to dynamic structure reference must evaluate to a valid field name.
Error in assignment3_question2b (line 7)
F = @(x)-8*x.(1+x.^2).^2 % antiderivative of f
Error in assignment3_question2b (line 8)
ref = F(b) - F(a);
Torsten
Torsten le 5 Déc 2022
F = @(x)-8*x.*(1+x.^2).^2; % antiderivative of f
instead of
F = @(x)-8*x.(1+x.^2).^2; % antiderivative of f
But the antiderivative of f is of course
F = @(x) 4*atan(x)

Connectez-vous pour commenter.

Catégories

En savoir plus sur Special Functions dans Help Center et File Exchange

Tags

Community Treasure Hunt

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

Start Hunting!

Translated by