How to solve this error: =: nonconformant arguments (op1 is 1x1, op2 is 100x1)?

This is the code I am using.

m1=3936/10;
m2=3936/20;
c1=3936/10;
c2=3936/20;
k1=3936;
k2=3936/2;
T = linspace(0, 10)'; % Time
f = 0.1; % Frequency
Am = 10;  % Phase
F = Am*sin(2*pi*f*T); % Sin wave input

function dydt = damper_sys(t,y,m1,m2,c1,c2,k1,k2,F)
    dydt=zeros(4,1);
    dydt(1)=y(2);
    dydt(2)=-(k2/m2)-(c2/m2)+(k2/m2)+(c2/m2);
    dydt(3)=y(4);
    dydt(4)=(k2/m1)+(c2/m1)-(k1+k2)/m1-(c1+c2)/m1 + F/m1;
end

tspan=[0 10];
init=[0;0;0;0];
options=odeset('Maxstep',0.1);
% [t,y]=ode45(@(t,y) damper_sys(t,y,m1,m2,c1,c2,k1,k2,F),tspan,init,options);

The given error is,

"error: =: nonconformant arguments (op1 is 1x1, op2 is 100x1) error: called from damper_sys at line 6 column 12 @<anonymous> at line 1 column 20 starting_stepsize at line 53 column 5 ode45 at line 196 column 25"

[Matt J]

Please copy/paste the error message.

[MD SAIFUL]

error: =: nonconformant arguments (op1 is 1x1, op2 is 1x20)

Answer 1

[Jan]

T = linspace(0, 10)'; % Time
f = 0.1; % Frequency
Am = 10;  % Phase
F = Am*sin(2*pi*f*T); % Sin wave input

Now F is a [100, 1] vector.

In the function t be integrated:

dydt(4) = (k2/m1) + (c2/m1) - (k1+k2) / m1 - (c1 + c2) / m1 + F / m1;
% ^ scalar                                                    ^ [100, 1]

This must fail, because the right side is a vector and the left side is a scalar.

[Kasun Madusanka]

Thank you very much for your help.