MATLAB Function Generates the Vertices of a Regular N-gon with Line Segments

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My task is to write a MATLAB function that generates the verticies of a regular n-gon and draws a line segment between each pair of verticies. The routine is only to plot one line segment at a time and the graph can only be generated by one "plot" command. I have a very rough outline of a program written up. There are some issues with the program. It plots one less vertice than n and I have no line segments connecting every vertice. Please help me to figure out where to go next with my program.
function e3(n)
%
%
t = linspace(0,1,n);
x = cos(t.*2*pi);
y = sin(t.*2*pi);
plot(x,y)
axis off
axis equal

Answers (2)

Ameer Hamza
Ameer Hamza on 3 Dec 2020
Edited: Ameer Hamza on 3 Dec 2020
You need n+1 points, because points at angle of 0 and 2*pi are same.
t = linspace(0,1,n+1);
Can you explain, what do you mean by connecting all the vertices?
  7 Comments
Ameer Hamza
Ameer Hamza on 3 Dec 2020
Try this
n = 15;
t = linspace(0,1,n+1);
x = cos(t.*2*pi);
y = sin(t.*2*pi);
[m1, m2] = ndgrid(1:n);
combs = unique(sort([m1(:) m2(:)],2), 'rows');
combs(diff(combs,[], 2)==0, :) = [];
hold on
for i = 1:size(combs,1)
plot(x(combs(i,:)), y(combs(i,:)), 'b')
end
axis off
axis equal
Sophie Culhane
Sophie Culhane on 4 Dec 2020
I am not able to use commands "hold on", "ndgrid", "sort", or "diff" as we have not learned those yet. Is there another way to go about this problem without those commands?

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Steven Lord
Steven Lord on 4 Dec 2020
You might find the degree-based trig functions sind and cosd useful. If you need to work exclusively with radians, the sinpi and cospi functions may be useful as well.
Finally for your iterative plotting either the comet or animatedline and addpoints functions may be of use.

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