MATLAB ODEs using ode45

Hello everyone. I am trying to solve 3 ODEs, so I have put them in 3 different function files. I am trying to call them in my script file, but I am always getting major errors. Can someone help me out please?

equationA.m

function dy1 = equationA(y1)

    k1 = 0.0005;
    dy1 = -k1*y1;
end

equationB.m

function [dy01,dy2,dy] = equationB(y1,y2)

dy01 = 0.0005*y1;

dy2 = - 0.0002*y2;

dy = dy01 + dy2; end

equationC.m

function dy3 = equationC(y3)

k2=0.0001;

dy3 = k2*y2;

end

ode.m (script file)

[T1,Y1] = ode45(@equationA,[0,10],0.0005);

[T2,Y2] = ode45(@equationB,[0,10],0);

[T3,Y3] = ode45(@equationC,[0,10],0.0001);

plot(T1,Y1,'*');

hold on

plot(T2,Y2,'-');

hold on

plot(T3,Y3,'+');

Answer 1

[Torsten]

The ODE function file must be of the form

dydt = myfun(t,y)

In all three cases above, your function file differs from this prescribed form.

Best wishes

Torsten.