Why is it only plotting points, not multiple line graphs?

This is the code that I am having a problem with. The UDF I am using will be attached. I do not know how to get multiple line graphs for each of the different velocities that I get. I used the 's' at the plot so that I could clarify to myself if it was actually plotting or not. I was wondering if there was some way to do this with the while loop and not getting rid of it. 

clc
clear
close all
V = 100;
hold all
while V<=500    
  t = [0:.1:30];
  h = 10;
  A = pi / 6;
  hold all
  [MaxY] = projectile(t, A, V, h);
  plot(MaxY,V,'s')
  V = V + 10;
end
title('Launch Velocity vs. Vertical Distance') %Give the Graph a title
xlabel('Maximum Projectile Vertical Distance (m)') %Lable the X-axis
ylabel('Launch Velocity (m/s)')

Answer 1

[KSSV]

Read about hold on

[Jack Gallagher]

hold on is the same as the hold all function that I am using in my script. I even tried switching the two, but nothing changed.

[KSSV]

YOu should run like this:

while V<=500

      t = [0:.1:30];
      h = 10;
      A = pi / 6;
      hold all
      [x, y, MaxY, X_at_MaxY, T_at_MaxY] = projectile(t, A, V, h);
      plot(MaxY,V,'.')

      V = V + 10;
  end

[KSSV]

V = 100;

X = zeros([],1) ; 
Y = zeros([],1) ;
count = 0 ;
while V<=500
    count = count+1 ;
    t = [0:.1:30];
    h = 10;
    A = pi / 6;
    X(count) = V ; 
    [x, y, MaxY, X_at_MaxY, T_at_MaxY] = projectile(t, A, V, h);
    Y(count) = MaxY ;

      V = V + 10;
  end
  plot(Y,X,'.-r')

title('Launch Velocity vs. Vertical Distance') %Give the Graph a title
xlabel('Maximum Projectile Vertical Distance (m)') %Lable the X-axis
ylabel('Launch Velocity (m/s)')

[Jack Gallagher]

Thank you for helping me with this.