solving differential equations with ode 45

Hi everyone,

I have a little problem using ode45 to solve this equation with initial conditions . But every time i try to run my script, i get this message of error

Error in Ryelandt_288861_Assignment2>@(t,z)EX_3_ode(z,t,M(1),c,c3,J)

Error in odearguments (line 90)

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

Error in ode45 (line 115)

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

Error in Ryelandt_288861_Assignment2 (line 33)

[t_out1,Z_out1] = ode45( @(t,z) EX_3_ode(z,t,M(1),c,c3,J), xx, IC1, opts);

Could someone help me with this ?

    %% Initiate the script 
clc; clear; close all
xx = linspace(0,10,1e3).';

%% Define the parameters 
Ct= 200;                %[J/K]
ht=140;                 %[W/m^2K]
At=0.02;                %[m^2]
he=200;                 %[W/m^2K]
Ae=pi;                  %[m^2]
Te= 298;                %[K]
V=6*pi;                 %[m^3]
rho=1;                  %[kg/m^3]
cp=4200;                %[J/kgK]
J=300;                  %[kgm^2]
c=2;                    %[Nms]
c3=0.1;                 %[Nms^3]
cq=0.09;                %[Ws^4]
M=[5,15,20,25,55];      %[Nm]
%% Question 3
%initial conditions 
IC1=[0; 0];
opts= odeset('RelTol',1e-8,'AbsTol',1e-10);

[t_out1,Z_out1] = ode45( @(t,z) EX_3_ode(z,t,M(1),c,c3,J), xx, IC1, opts);
%% Function definition
function dzdt1 = EX_3_ode(z,M,c,c3,J)
dzdt1(1,1) = z(2) ;
dzdt1(2,1) =(M-c.*z(2)-c3.*z(2)^3)./J ;
end

Answer 1

[Ameer Hamza]

You need to change it like this

[t_out1,Z_out1] = ode45( @(t,z) EX_3_ode(t,z,M(1),c,c3,J), xx, IC1, opts); % first input of EX_3_ode is t
%% Function definition
function dzdt1 = EX_3_ode(t,z,M,c,c3,J) % first input should be t, if it is not used, replace it with ~
dzdt1(1,1) = z(2) ;
dzdt1(2,1) =(M-c.*z(2)-c3.*z(2)^3)./J ;
end

[Guillaume Ryelandt]

Thank you verry much!! it works now

[Ameer Hamza]

Glad to be of help.