Differentiate an inline function
13 vues (au cours des 30 derniers jours)
Afficher commentaires plus anciens
Hi!
I have an assignment in Matlab and I need to find a function's 8th and 9th derivate. This function is an inline function, as it is an input from the user.
I have been trying to use the function diff, but it tells me: «Function 'diff' is not supported for class 'inline'.»
Any ideas?
6 commentaires
Walter Roberson
le 23 Nov 2012
syms x
f = sym(string_from_input);
diff(f,x,x,x,x,x,x,x,x)
Réponse acceptée
Plus de réponses (1)
Matt J
le 23 Nov 2012
Modifié(e) : Matt J
le 23 Nov 2012
You cannot do symbolic differentiation on inline functions. If you don't have the Symbolic Toolbox, you will have to either consider a specific family of functions and pre-analyze their derivatives. Or, if you want to do numeric differentiation,
t=linspace(0,T,N);
f = vectorize(inline(string_from_input));
result = diff(f(t),8)./( t(2)-t(1) )^8;
0 commentaires
Voir également
Catégories
En savoir plus sur Function Creation dans Help Center et File Exchange
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!