how to solve error mentioned in following program?

This is my program

[t,Vc]=ode45('capvolt',[0 20e-3],[0])
%capvolt is the function file name
subplot(1,2,1)
plot(t,Vc,'r')
grid
title('Vc')
xlabel('time in sec')
ylabel('voltage Vc')
Vc_analy=10*(1-exp(-10*t))
subplot(1,2,2)
plot(t,Vc_analy)
grid
xlabel('time in sec')
ylabel('voltage Vc_analy')
title('Vc_analy')

%program of the function file capvolt

dVc=100-10*Vc
function dVc=capvolt(t,Vc)

And the error i am facing is : Function definitions are not permitted at the prompt or in scripts.

Answer 1

[Azzi Abdelmalek]

Your function is not correct. It should be

function dVc=capvolt(t,Vc)
dVc=100-10*Vc

Save this function as capvolt.m, then you can call your function

[t,Vc]=ode45('capvolt',[0 20e-3],[0])