A little more like this? (I've used arbitrary values for initial conditions etc.)
N = 200; % points to be taken
g = 9.8; % acceleration due to gravity (m/s^2)
dt = 0.01; % time step for time range of 1-10 sec.
theta = 45; %input('Angle of projection(in degrees): '); % Allows user to input
h = 1; %input('Initial height (in meters): ');
v_0 = 5; %input('Initial velocity (in m/s): ');
% Initial conditions below
x(1) = 0; % intial x position (m)
y(1) = h; % intial y position (m)
t(1) = 0; % inital time (s)
tf = N*dt; % final time (s)
v(1) = v_0; % initial velocity (m/s)
v_x = v_0*cos(theta); % "x" component of the velocity
v_y = v_0*sin(theta); % "y" component of the velocity
v_x(1) = v_x;
v_y(1) = v_y;
n = 1;
for n = 1:N
v(n+1)=sqrt((v_x(n)^2)+(v_y(n)^2));
v_x(n+1) = v_x(n);
v_y(n+1) = v_y(n) - g*dt;
x(n+1) = x(n) + v_x(n)*dt;
y(n+1) = y(n) + v_y(n)*dt;
t(n+1) = t(n) + dt;
if y(n+1)<0
break
end
end
plot(x,y),grid
xlabel('x'),ylabel('y')
