Loop imagesc together for traffic simulation

So i have a school assignment that is asking us to make a road with 2 cars traveling in opposite directions using imagesc. My issue is I cannot get the loop to show both cars at once as when one car gets plotted the other gets deleted. I know there are specific matlab programs to make road simulations but we can't use that. My code is this

rw = 11;

rl = 40;

road = zeros(rw,rl);

road2= zeros(rw,rl);

xpos = 1;

ypos = 3;

xpos2= 39;

ypos2= 7;

road(ypos,xpos) = 1;

road2(ypos2,xpos2)=1;

imagesc(road)

axis equal

for t = 0 : 5

road(ypos,xpos) = 0;

xpos = xpos + 1;

road(ypos,xpos) = 1;

imagesc(road); hold on

t1 = sprintf('time = %f sec' , t);

title(t1);

axis equal

pause(0.5)

road2(ypos2,xpos2)=0;

xpos2 = xpos2 - 1; hold on

road2(ypos2,xpos2)=1;

imagesc(road2)

t1 = sprintf('time = %f sec' , t);

title(t1);

axis equal

pause(0.5)

end

Answer 1

[Pavan Guntha]

Hi Anthony,

You could look at the following code:

rw = 11;
rl = 40;
road = zeros(rw,rl);
xpos1 = 1;
ypos1 = 3;

xpos2 = 39;
ypos2 = 7;
road(ypos1, xpos1) = 1;

figure(1);
clf;
imagesc(road)
axis equal
hold on

for t = 0 : 20
    road(ypos1,xpos1) = 0;

    xpos1 = xpos1 + 1;
    road(ypos1,xpos1) = 1;
    imagesc(road);

    t1 = sprintf('time = %f sec' , t);
    title(t1);
    pause(0.1)

    road(ypos2,xpos2) = 0;
    xpos2 = xpos2 - 1;
    road(ypos2,xpos2) = 1;
    imagesc(road)
    pause(0.1)
end

Calling imagesc within a loop refreshes the figure window even if you put "hold on" in your case because you have considered two roads, one each for the 2 cars. Instead you can consider a single road and appropriately vary the positions of car1 and car2 as shown in the previous code.

Hope this helps!