How code lines that move apart?

How would I be able to have 2 lines moving apart at a given rate? For example, 2 lines (L1 and L2) both starting at (0,0) and then moving apart incrementally to L1=x=1, L2=x=-1; then L1=x=2 L2=x=-2 and so on.

[Geoff Hayes]

Conrad - what is the y-coordinate as the two lines move apart? What is the end-point of each line (since the origin for both is (0,0))? Please provide more details.

[Conrad Suen]

Would the y coordinate matter? If the y coordinate helps give a bounds for the line, then any y value could be used. Essentially I was wondering how I could code 2 arbitrary lines spreading apart.

[KSSV]

I don't think you would be able to draw two lines with the give information. One more condition must be specified like the angle between the two lines, which helps in calculating the slopes of each lines.

[Conrad Suen]

The lines would be vertical (simply x=constant). There is no way to plot lines moving apart from one another? I attached a picture to possibly help. I can restrict the y coordinate to whatever value needed (ie y cannot be greater than 10)

[Conrad Suen]

I want to do something like this except each line needs to be the same length.

t = 0;
last = 10;
step = 0.1;

while t <= last
    k=0
    i=5
    k=0
%    x=[k+t,k-t]
%    y=[5,-5]
   x=[t,t]
   y=[-k+t,k-t];
plot (x,y)
    drawnow
    t = t+step;
   hold on

end

Answer 1

[Vidya Viswanathan]

Hi Conrad,

Is this what you are looking for?

x=[-2:0.1:2];
y=[-10 10];
x=repmat(x,[2 1]);
plot(x,y)

This code snippet gives the following figure:

In this case, I have considered only two points in the y-axis. If you need multiple points between your required limit (say -10 and 10), you can modify the code in the following manner:

y=[-10:0.1:10];  
x=[-2:0.1:2];
x=repmat(x,[length(y) 1]);
plot(x,y)

You'll basically get the same figure but will multiple data points in each straight line. I hope this helps.

Regards,

Vidya Viswanathan

[Conrad Suen]

Almost! I figured it out after some tinkering throughout the day; here's what I came up with:

close all
clear
clc
t = 0;
last = 10;
step = 0.1;

while t <= last
   x=[t,t];
   z=[-t,-t];
   y=[5,-5];
   plot (x,y)
   plot (z,y)
   drawnow
   t = t+step;
   axis equal
   hold on

end
hold on