# Why am I getting errors with this code?

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J on 22 Feb 2015
Commented: J on 22 Feb 2015
Could someone help me figure out why I am getting all kinds of errors with my code please. I have attached the *.m file containing my code. Thank you very much.
J on 22 Feb 2015
No, they are all in the same file.

Greig on 22 Feb 2015
Edited: Greig on 22 Feb 2015
There are a few issues here. First of all, you cannot declare functions in a standard m-file script. They have to be in separate m-files, or trajectory.m needs to be a function.
I recommend renaming it to "Get_trajectory.m" and making the start and end
function Stats = Get_trajectory
.... % all the other functions
end % this is needed since all other function use end
Second, by defining trajectory as a function, we need to declare what the output should be. I guess it is all the output from your various functions? If so, then we need to call your various functions get their output and return this as the output of the Get_trajectory function (the "Stats" variable above). So, add something like this after you ask for the user input...
[xt,yt] = trajectory(v0,theta,t,g);
ymax = peakheight(v0,theta,g);
tmax = timeflight(v0,theta,g);
xmax = range(v0,theta,g);
Stats = [xt, yt, ymax, tmax, xmax];
Third, in the peakheight function, you a missing a * in the ymax calculation
function [ymax] = peakheight(v0,theta,varargin)
if nargin == 2
g=9.8; % if g not specified g=9.8
ymax = ((v0^2)*((sin(theta))^2))/2*g;
elseif nargin == 3
%if the user enter the value for g
g=varargin{1};
ymax = ((v0^2)*((sin(theta))^2))/2*g;
end
end
Lastly, to call the function simply type
Stats = Get_trajectory;
Type in the prompted inputs, and the stats variable will contain all of the output you need. I have attached my updated version for you to see.
Edit: The file is now attached!
J on 22 Feb 2015
Greig, I really appreciate your help. Thank you very much.