How to create a plot with this code?

When trying to plot a graph nothing but the x axis and y axis are displayed in the figure. The code is for drawing the approximate path of a projectile which is experiencing drag.

close all
%constants and starting conditions
g =-9.81;
A = 0.25 * pi * (0.01512); %with 15.12mm the diameter of the projectile
ro = 1.293; %Binas' air density at 20C at sea level
c = 0.47; %drag coefficient for a sphere
B = 45; %launch angle
Xx = 0;
Xy = 1-sin(B)*0.202; %projectile-floor height in meters
Vc = 10.66; %launch speed in meters per second
Vx = sin(B)*Vc; %horizontal speed vector
Vy = cos(B)*Vc; %vertical speed vector
dt = 0.1; %timestep
m = 0.001684;%projectile mass in kilograms
awx(1) = 0;
awy(1) = 0;
dVy(1) = 0;
dVx(1) = 0;
dXx(1) = 0;
dXy(1) = 0;
Fwx(1) = 0;
Fwy(1) = 0;
t(1) = 0;
%model
while Xy >= 0

      ax = awx;
      Vx = Vx+dVx;
      dVx = ax*dt;
      Xx = Xx+dXx;
      dXx = Vx*dt+0.5*ax*(dt)^2;

      ay = g+awy;
      Vy = Vy+dVy;
      dVy = ay*dt;
      Xy = Xy+dXy;
      dXy = Vy*dt+0.5*ay*(dt)^2;

      Vd = sqrt((Vx)^2+(Vy)^2);%sum of both speed vectors in flight
      Fw = -0.5*ro*A*c*(Vd)^2;
      theta = atan((Vx)/(Vy));%angle of Vd in fight
      Fwy = cos(theta)*Fw;
      Fwx = sin(theta)*Fw;
      awx = (Fwx)/m;
      awy = (Fwy)/m;

      t = t+dt;

end
      plot(Xx,Xy)
    xlabel('x (m)')
    ylabel('y (m)')
  title('Projectile Path')

Answer 1

[Star Strider]

You need to subscript and save ‘Xx’ and ‘Xy’, I created ‘Xxv’ and ‘Xyv’ to do this, and also ‘tv’ to save the time vector if you need it.

This plots:

%model
k = 1;
while Xy >= 0

        ax = awx;
        Vx = Vx+dVx;
        dVx = ax*dt;
        Xx = Xx+dXx;
        dXx = Vx*dt+0.5*ax*(dt)^2;
        Xxv(k) = Xx;

        ay = g+awy;
        Vy = Vy+dVy;
        dVy = ay*dt;
        Xy = Xy+dXy;
        dXy = Vy*dt+0.5*ay*(dt)^2;
        Xyv(k) = Xy;

        Vd = sqrt((Vx)^2+(Vy)^2);%sum of both speed vectors in flight
        Fw = -0.5*ro*A*c*(Vd)^2;
        theta = atan((Vx)/(Vy));%angle of Vd in fight
        Fwy = cos(theta)*Fw;
        Fwx = sin(theta)*Fw;
        awx = (Fwx)/m;
        awy = (Fwy)/m;

        t = t+dt;
        tv(k) = t;

        k = k + 1;

end
      plot(Xxv,Xyv)
    xlabel('x (m)')
    ylabel('y (m)')
  title('Projectile Path')

You likely still have some work to do on this.