How can I plot a sym variable?
1 vue (au cours des 30 derniers jours)
Afficher commentaires plus anciens
I am trying to plot a function and it's derivative, but
syms x y
y=4*x*cos(x)+2*x^cos(x^2)
dydx=diff(y)
plot(y)
gives me an error that I cannot convert double to sym. I know I can plot a function and its derivative using LINSPACE but I want the analytical derivative value as well. How can I plot y and dydx? I also know I can use "EZPLOT" but that doesn't let me do very much with the plotter. Is it possible to plot a symbolic variable and if it is now, how do I get an analytical derivative AND plot it in MatLab?
1 commentaire
Walter Roberson
le 4 Mar 2013
The analytic derivative will be a formula, and you cannot plot() a formula. You could put the formula up as text using text()
Réponse acceptée
Youssef Khmou
le 4 Mar 2013
hi did you try this :
syms x y dy
y=4*x*cos(x)+2*x^cos(x^2)
dy=diff(y,1);
figure, ezplot(y); hold on; ezplot(dy);
2 commentaires
Youssef Khmou
le 4 Mar 2013
and if you move back to numeric ? fine ?
xAxis=[0:0.1:10];
Y=subs(y,xAxis);
DY=subs(dy,xAxis);
figure, plot(Y), hold on, plot(DY,'r')
Plus de réponses (0)
Voir également
Catégories
En savoir plus sur Conversion Between Symbolic and Numeric 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!