How to correct ode45 errors?

I am trying to execute the following code

clear all

clc

global mdot mass Ti UA Cp Ts

mdot=0.2;

mass=760;

Cp=2300;

UA=191.66;

Ts=150;

Ti=25;

tspan=[0:10:3000];

T0=25;

[t,T]=ode45(@(t,T) Heatingcoil(t,T,tspan,T0);

disp('Time(sec) Temp(deg cel)');

disp([t,T]);

plot(t,T);

xlabel('Time(sec)');

ylabel('Temp(deg cel)');

title('Time vs Temp');

dT=Heatingcoil(t,T);

global mdot mass Ti UA Cp Ts

dT=(mdot*(Ti-T)+(UA*(Ts-T)/Cp))/mass;

But I am getting the following erros:

Error using feval

Undefined function 'Heatingcoil' for input arguments of type 'double'.

Error in odearguments (line 87)

f0 = feval(ode,t0,y0,args{:}); % ODE15I sets args{1} to yp0.

Error in ode45 (line 113)

[neq, tspan, ntspan, next, t0, tfinal, tdir, y0, f0, odeArgs, odeFcn, ...

Error in heatingwithcoil (line 12)

[t,T]=ode45(@Heatingcoil,tspan,T0);

Please help me in fixing these errors

Answer 1

[Star Strider]

First, do not use global variables!

Second, you need to declare your function correctly, and pass the extra parameters to it.

This works (in R2018b):

mdot=0.2;
mass=760;
Cp=2300;
UA=191.66;
Ts=150;
Ti=25;
tspan=[0:10:3000];
T0=25;
[t,T]=ode45(@(t,T) Heatingcoil(t,T,mdot, mass, Ti, UA, Cp, Ts),tspan,T0);
disp('Time(sec)  Temp(deg cel)');
disp([t,T])

figure
plot(t,T);
xlabel('Time(sec)');
ylabel('Temp(deg cel)');
title('Time vs Temp');

function dT=Heatingcoil(t,T,mdot, mass, Ti, UA, Cp, Ts)
dT=(mdot*(Ti-T)+(UA*(Ts-T)/Cp))/mass;
end

See the documentation on Function Basics (link).