My script is working wrong with nested for loops

d = input('enter a number:')
figure
for b = 0:0.5:d
    plot(b, 0, '*k')
    pause(0.05)
end
 for c = 0:0.5:d
 plot(0, c, '*k')
 plot(d, c, '*k')
 pause(0.05)
 end
for b = 0:0.5:d
    plot(c, d, '*k')
    pause(0.05)
end

I couldn't run this script nested for-end loops. How can I do that? It is working correct like this. I want to make lines thinner. I couldn't use Linewidht correctly probably. Can I use axes command differently or use something else?

[Jan]

There are no nested loops in this code. "Nested" would be:

for i1 = 1:10
  for 12 = 1:10
    ...
  end
end

How do "I couldn't run this script" and "It is working correct like this" match?

"I want to make lines thinner." - how did you try this? Post the code, which is failing, not some other code, which is running.

"Can I use axes command differently" - yes, of course. Differently then what?

[sky2]

I tried to to say I couldn't run this script when I try to use nested loops. Sorry for that.

[Jan]

But there are no nested loops and no need for nested loops. If you have a problem with some code, which contain nested loops, post this code and explain the problems.

Answer 1

[DGM]

I'm not sure what you were trying to nest here. Would something like this suffice?

a = input('enter a number:')

clf
figure(gcf)
axes('NextPlot', 'add', ...
    'XLim', [-1, a+1], 'YLim', [-1, a+1], ...
    'DefaultLineMarkerSize', 3);

for s=1:3
    for b = 0:0.5:a
        switch s
            case 1
                plot(b, 0, '*k')
            case 2
                plot(0, b, '*k')
                plot(a, b, '*k')
            case 3
                plot(b, a, '*k')
        end
        pause(0.05)
    end
end

for b = 0:0.5:a
    plot([0, a, a, 0, 0], [0, 0, a, a, 0], '-k')
end

As far as the lineweight goes, I don't know how thin you want it to be. You can set the linewidth property:

plot([0, a, a, 0, 0], [0, 0, a, a, 0], '-k','linewidth',0.1)

but the thinnest line that it can display is 1px wide.

Answer 2

[Jan]

Plotting the line does not need a loop:

% for b = 0:0.5:a   % The body does not depend on b, so omit the loop
    plot([0, a, a, 0, 0], [0, 0, a, a, 0], '-k')
% end

What is the problem with which line width?

plot([0, a, a, 0, 0], [0, 0, a, a, 0], '-k', 'LineWidth', 3)

[DGM]

oof. I didn't even catch that.

[sky2]

Oh my bad. If I want to use hold on instead of using axes. Do I need to write markersize every plot line right?

[Jan]

"use hold on instead of using axes" - this is not meaningful. hold on sets the NextPlot property of the axes to 'add'. You can do this directly also.

You can either define the MarkerSize inside each plot command, or as default in the axes object. It is a question of taste.