# I am unable to run this program.

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Puja on 27 Jan 2024
Answered: Sam Chak on 27 Jan 2024
second_oder_ode
Error using odearguments
SECOND_ODER_ODE/RHS returns a vector of length 3, but the length of initial conditions vector is 2. The vector returned by SECOND_ODER_ODE/RHS and the initial conditions vector must have the same number of elements.

Error in ode45 (line 104)
odearguments(odeIsFuncHandle,odeTreatAsMFile, solver_name, ode, tspan, y0, options, varargin);

Error in solution>second_oder_ode (line 19)
[t,x]=ode45( @rhs, t, [initial_x initial_dxdt] );
function second_oder_ode
% SOLVE d^2x2/dt^2 = (k(Asin(wt)-x2)-cA(dx/dt)/h)/m
% initial conditions: x(0) = 0, x'(0)=0
t=0:0.001:1;% time scale
initial_x = 0;
initial_dxdt = 0;
c=0.001;
h=0.01;
k=100;
m=1;
w=10;
A=2;
[t,x]=ode45( @rhs, t, [initial_x initial_dxdt] );
plot(t,x(:,1));
xlabel('t'); ylabel('x');
function dxdt=rhs(t,x)
dxdt_1 = x(2);
dxdt_2 = (k*(A*sin(w*t)-x)-(c*A/h)*x(2))/m;
dxdt=[dxdt_1; dxdt_2];
end
end
Dyuman Joshi on 27 Jan 2024
Please share the mathematical definition of the equation you are trying to solve.

Sam Chak on 27 Jan 2024
I've indicated the location where you should apply a fix to it.
second_oder_ode
function second_oder_ode
% SOLVE d^2x2/dt^2 = (k(Asin(wt)-x2)-cA(dx/dt)/h)/m
% initial conditions: x(0) = 0, x'(0)=0
t=0:0.001:1;% time scale
initial_x = 0;
initial_dxdt = 0;
c=0.001;
h=0.01;
k=100;
m=1;
w=10;
A=2;
[t,x]=ode45( @rhs, t, [initial_x initial_dxdt] );
plot(t,x(:,1));
xlabel('t'); ylabel('x');
function dxdt=rhs(t,x)
dxdt_1 = x(2);
dxdt_2 = (k*(A*sin(w*t)-x(1))-(c*A/h)*x(2))/m;
% ^^^^
dxdt=[dxdt_1; dxdt_2];
end
end