MATLAB: Plotting help. No line or points appearing on plot

plottingscript

So, im trying to write a script to plot x=x1 + tV1cos(theta). The figure will generate but no points. What can I do to fix this? Any help would be extremely appreciated. Thank you in advance
%% Get user input
launch_angle= input('Enter launch angle in degrees : ');
xo = input('Enter initial x position in meters: ');
xt = input('Enter target x position in meters: ');
yt = input('Enter target y position in meters: ');
tt = input('Enter target hitting time in seconds: ');
te = input('Enter end time in seconds: ');
g=9.8;
% Calculate Vo
vo = (xt-xo)/(tt*(cos(launch_angle * (pi/180))))
%% Display the result
disp(['Initial Velocity in metres per second is: ', num2str(vo)]);
%% Calculate yo
yo = yt – (tt*vo*(sin(launch_angle * (pi/180))))+(0.5*g*tt^2)
%% Display the result
disp(['Initial y positon in metres is: ', num2str(yo)]);
%% Equations to plot End pt
xe = xo + (te*vo*cos(launch_angle * (pi/180)))
ye = yo + (te*vo*(sin(launch_angle * (pi/180))))-(0.5*g*te^2)
%% Plot end point
figure
plot(xe',ye','-r');

Best Answer

You need to make time as vector. Then you can plot the trajectory, if i understand it right.
See the code below, it plots xe vs ye according to your prog 
launch_angle= input('Enter launch angle in degrees : ');
xo = input('Enter initial x position in meters: ');
xt = input('Enter target x position in meters: ');
yt = input('Enter target y position in meters: ');
tt = input('Enter target hitting time in seconds: '); % total time to hit target in s
te = input('Enter end time in seconds: '); % end time at which target is destroyed
g=9.8;
te = tt:-0.1:te;   % calculate the time vector
% Calculate Vo
vo = (xt-xo)/(tt*(cos(launch_angle * (pi/180))))
 
%% Display the result

disp(['Initial Velocity in metres per second is: ', num2str(vo)]);
%% Calculate yo
yo = yt - (tt*vo*(sin(launch_angle * (pi/180))))+(0.5*g*tt^2)
%% Display the result
disp(['Initial y positon in metres is: ', num2str(yo)]);
 
%% Equations to plot End pt
 
xe = xo + (te*vo*cos(launch_angle * (pi/180)))
ye = yo + (te*vo*(sin(launch_angle * (pi/180))))-(0.5*g*te.^2)
 
%% Plot end point
 
figure
plot(xe',ye','-r');
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