why am I getting this error?

%the error

Not enough input arguments.

Error in Exam2>odefun (line 92)

f=[0 ; (2*f0-f0.*heaviside(t,t1)-2*f0.*heaviside(t,t2))];

Error in Exam2 (line 65)

[t,x]=ode45(odefun,tspan,IC);

%my ode45 call

IC=[x0 v0];

tspan=0:dt:tf;

[t,x]=ode45(odefun,tspan,IC);

%my function

function xdot=odefun(t,x)

global f0 wn t1 t2

A=[0 1 ; -wn^2 0];

f=[0 ; (2*f0-f0.*heaviside(t,t1)-2*f0.*heaviside(t,t2))];

xdot=A*x+f;

end

Answer 1

[Steven Lord]

[t,x]=ode45(odefun,tspan,IC);

This attempts to call your odefun function with 0 input arguments and use the function handle it returns as the first input argument to ode45. If you want the first input argument to ode45 to be a function handle to odefun (you want ode45 to use odefun to evaluate the right-hand side of your system of ODEs), you need to add one character.

[t,x]=ode45(@odefun,tspan,IC);

Answer 2

[Cris LaPierre]

Have you created your own heaviside function? The one created by MathWorks only accepts a single input. The one you are using has 2, and apparently expects more.

[Michael Abend]

ok so that has to be the issue thank you?