for loop skipping an iteration

My code is for simulating Buffon's Needle throwing experiment.

So I wanted to simulate the throwing needles part. The following code was supposed to create 3 figures each with 10, 100 and 1000 needles respectively.

fig=0;

n=[10 100 1000];

for n=n

fig=fig+1;

figure(fig)

hold on

for s=1:n

needle

end

hold off

end

function needle

mid_x=0.5+9*rand(1,1);

mid_y=0.5+9*rand(1,1);

slope=tan(2*pi*rand(1,1));

x1=mid_x+1/sqrt((1+slope^2));

y1=slope*(x1-mid_x)+mid_y;

x2=mid_x-1/sqrt((1+slope^2));

y2=slope*(x2-mid_x)+mid_y;

plot([x1 x2],[y1 y2])

end

however, it's showing two figures; one titled figure 1 but with 100 lines and the other figure 3 with 1000 lines. Can anyone tell me where the problem is?

[Bjorn Gustavsson]

One general advice is to never ever again use the construct

n=[10 100 1000];
 for n=n
 end

Nothing good can come out of that in the long run. Use different names, if for no other reason to make it clear which is what where.

[Nushaer]

I'm just starting out. Thanks for the tip.

Answer 1

[Karim]

I would use a separate variable for the for-loop. See below with the adjusmtents.

n = [10 100 1000];

for i = 1:numel(n)
    
    figure(i)
    hold on
    for s = 1:n(i)
        needle
    end
    hold off
    grid on
    title("Figure with "+num2str(n(i))+" needles")
    
end

function needle
mid_x=0.5+9*rand(1,1);
mid_y=0.5+9*rand(1,1);
slope=tan(2*pi*rand(1,1));
x1=mid_x+1/sqrt((1+slope^2));
y1=slope*(x1-mid_x)+mid_y;
x2=mid_x-1/sqrt((1+slope^2));
y2=slope*(x2-mid_x)+mid_y;
plot([x1 x2],[y1 y2])
end

[Nushaer]

My gratitudes