Need help with plot

Question

Peter Denardo 2021-12-17

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/1612840-need-help-with-plot

评论： Peter Denardo 2021-12-17

Having trouble figuring out how to plot my 3 trajectories on a graph for the below program. Your help is appreciated. Thank you.

% All distances and heights measured in meters, time in seconds, velocity in m/s, angles in degrees and
%%acceleration in m/s^2
clear all
clc
H0 = 8;
return_height_tolerance = .001;
theta_0=26;
g=9.81;
dAC=16;
eR=.94 ;
H3=0;
v0=1;
err = 5;
counter=1;
while err>0.008
    %Iteration Control
    v0 = v0 + .001;
    counter=counter+1;
    
    %initial velocities in both directions
    v0x=v0*cosd(theta_0);    %Trig
    v0y=v0*sind(theta_0);   %Trig
    
    %Point B = Maximmum height along trajectory path 1
    H1=H0+v0y^2/(2*g);
    
    %trajectory path 1
    H2=H0+dAC*tand(theta_0)-g/(2*v0x^2)*dAC^2;
    
    %velocities in x and y direction at max height
    v1x=v0x;    %Zero Acceleration
    v1y=(sqrt(v0y^2-2*g*(H1-H0)));
    
    %velocity just prior to hitting wall
    v2x=v1x;  
    v2y=sqrt(v1y^2+2*g*((H0+H1)-(H0+H2)));
    v2=sqrt(v2x^2+v2y^2);
    
    %NEW NEW
    %H2 = H1 - v2y^2/(2*g);
    
    %velocity just after hitting the wall
    v3x=v2x*eR;
    v3y=v2y;
    v3=sqrt(v3x^2+v3y^2);
    theta_3_ref=atand(v3y/v3x);  % Trig: Reference Triangle
    theta_3_abs=theta_3_ref+180; % Absolute Angle (Quadrant "3")
    
    %velocity just prior to hitting ground
    v4x=v3x;
    v4y=(sqrt(v3y^2-2*g*(H3-H2)));
    v4=sqrt(v4x^2+v4y^2);
    theta_4_ref=atand(v4x/v4y);
    theta_4_abs=theta_4_ref+180;
    
    %Distance between wall and ground
    A=(-g/(2*v3x^2));
    B=tand(theta_3_abs);
    C=(1/(2*g)*(v4^2-v3^2));
    
    %Quadratic formula for distance between wall and ground
    %%based on energy Conservation 2-3 022& Trajectory Eq. 2-3 equations
    dCD=(-B+sqrt(B^2-4*A*C))/(2*A);
    
    %trajectory path 2
    H3=H2+dCD*tand(theta_3_abs)-g/(2*v4x^2)*dCD^2;
    
    %velocity just after hitting the ground
    v5x=v4x;
    v5y=v4y*eR;
    v5=sqrt(v5x^2+v5y^2);
    theta_5_ref=atand(v5x/v5y);
    theta_5_abs=theta_4_ref+90;
    
    %distance between ground and return height
    dDA=-dAC-dCD;
    
    %trajectory path 3
    H4=H3+dDA*tand(theta_5_abs)-g/(2*v5^2)*dDA^2;
    
    %Flight time between point A & B
    time_AB=(H1-v0)/-g;
    %Flight time between point A & C
    time_AC=dAC/v0;
    
    %Flight time between point C & D
    time_CD=abs(dCD/v4);
    
    %Flight time between point D & return height
    time_D_return=abs(dDA/v5);
    
    %Update Error
    err = abs(H4-H0);
    
    %H2=H0+dAC*tand(theta_0)-g/(2*v0x^2)*dAC^2;
    %H3=H2+dCD*tand(theta_3_abs)-(g/(2*v3^2*(cosd(theta_3_abs))^2))*dCD^2;
    %H4=H3+dDA*tand(theta_5_abs)-(g/(2*v4^2*(cosd(theta_5_abs)^2)))*dDA^2; 
    
end
v0
v0y
v0x
v1y
v1x
v2
v2y
v4
dCD
dDA
H1
H2
H3
H4
time_AB
time_AC
time_CD
time_D_return
counter

2 个评论
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KSSV 2021-12-17

What variables you want to plot?

Peter Denardo 2021-12-17

I want to plot these 3 trajectories. I solved for the time on each of the trajectories so I am wondering if there is a similar method to plot them over a time to make it neater. H2, H3, and H4 are basically the final y cooridnate.

%H2=H0+dAC*tand(theta_0)-g/(2*v0x^2)*dAC^2;

%H3=H2+dCD*tand(theta_3_abs)-(g/(2*v3^2*(cosd(theta_3_abs))^2))*dCD^2;

%H4=H3+dDA*tand(theta_5_abs)-(g/(2*v4^2*(cosd(theta_5_abs)^2)))*dDA^2;

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Answer 1

KSSV 2021-12-17

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/1612840-need-help-with-plot#answer_857005

在 MATLAB Online 中打开

You can store the variables in while loop using:

iwant = zeros([],1) ;
counter=1;
while err>0.008
    counter = counter+1 ; 
    % do alculation for iwant/ update iwant 
    iwant(counter) = val ; 
end
% iwant is an array you can plot here 