MATLAB: Solving coupled ODE’s by ode45 / exp input error

Question

Hello,

I have a set of coupled differential equations that are in an .m file:

function dy = system_ex1(t, y)

dy = zeros (2 ,1);

dy(1) = -1.*exp^(-10./(y(2)+273)).*y(1);

dy(2) = 1000.*exp^(-10./(y(2)+273)).*y(1)-10.*(y(2)-20);

I solve it using ODE45 as such below:

Tspan = [0, 5];

IC = [1, 15];

[T, Y] = ode45(@system_ex1, Tspan, IC);

When I try to solve I am bombarded with messages. The first being "Error using exp" & "Not enough input arguments.". I believe that my ODE troubles stem from this but I also recieved many more ODE error messages as seen below:

Error using exp

Not enough input arguments.

Error in system_ex1 (line 7)

dy(1) = -1.*exp^(-10./(T+273)).*C;

Error in odearguments (line 90)

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

Error in ode15s (line 150)

odearguments(FcnHandlesUsed, solver_name, ode, tspan, y0, options, varargin);

Error in Task1_Call (line 13)

[T, Y] = ode15s(@system_ex1, Tspan, IC);

Any and all help is appreciated, especially with trying to understand the issues with the exp function.

Thank you,

Mike

Answer 1

exp(