MATLAB: In need of help with ODE45

MATLABode45

Hi, I'm new to MATLAB and I hope you can enlighten me on the usage of ODE45.
In my main script, 'inputprompts.m', I called a function HCRSK with the ODE45 solver, as follows:
   T0 = [Tc,Tsk; Tc,Tsk]; %initial values input by user 
   [t,T] = ode45(@HCRSK, [Tinit,Tend], T0);
Tinit and Tend are input by the user.
The HCRSK function uses the Tc and Tsk inputs and borrows the output of other functions using the same inputs. Other functions called are alpha, HSCR and HSSK. The code for the function is as follows:
function hcrsk = HCRSK(x,y)
 Wt=65;
Ht=1.77;
Cbt=1.28;
Ad = 0.202.*(Wt.^0.425).*(Ht.^0.725);
a = feval(@alpha, x,y);
TCCRA = ((1-a).*Wt.*Cbt)./Ad; 
hscr1 = feval(@HSCR,x,y);
Tcdot = hscr1./TCCRA; 
TCSKA = (a.*Wt.*Cbt)./Ad; 
hssk1 = feval(@HSSK,x,y);
Tskdot = hssk1./TCSKA;
hcrsk = [Tcdot; Tskdot]; %vector of Tc and Tsk rate equations"
Running the main script returns an error like so:
"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 inputprompts (line 64) [t,T] = ode45(@HCRSK, [Tinit,Tend], T0);"
HELP~~~!!

Best Answer

Your initial conditions vector has to be the same size as the vector returned by your ODE function.
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