function f1
%define tstart, tend and the number of time steps you want to take, n:
tstart = 0;
tend = pi/2;
n = 160;
tspan = linspace(tstart,tend,n);
%define the initial conditions making sure to use the right ordering
xinit = [0;0;0];
%Get x. I have left options as the default value so it's not included in the function call below
[t,x] = ode45(@integratingfunction, tspan, xinit)
%define the output variables:
y = x(:,1);
ydot = x(:,2);
ydotdot = x(:,3);
%Include whatever plotting functions you need to include here. You can plot anything you want: %y(t), _y(t), _y(y), _y(y), etc.
subplot(y(t),t)
plot
%plot3( ... ) % use this is you are plotting a 3D plot title(' ')
xlabel('t ')
ylabel('y ')
%zlabel(' ') % uncomment the last line if you are doing a 3D plot
%|||||||||||||-
%THE INTEGRATION FUNCTION
% This can either be in a separate or right at the bottom of the same le.
%Either way, the syntax is as follows:
function dxdt = integratingfunction(t,x)
%1. Define your constants - mass, gravity, etc.
%2. Define new variables: y=x(1), ydot=x(2), etc
%You don't have to do this, but is makes it a lot easier for others to decipher your code
%3. Write out your rst order system of ODE's:
dxdt = zeros(size(x));
dxdt(1) = ydot;
dxdt(2) = 5/(0.5*sin(y)-cos(y));
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