Question

I have a file a.txt which is like:

0 0 0 3 4 3
0 0 3 0 3 4
0 1 0 4 4 4
0 1 3 1 3 5
0 2 0 5 4 5
0 3 0 0 4 0

These are vertices of triangles [x1 y1 x2 y2 x3 y3] that I need to plot on a 6×6 grid.
I need to see these triangles on a single graph.

How can this be done in MATLAB?

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thanks a lot everyone!

finally what worked:

a = dlmread('a.txt');

clf
xlim([0 6])
ylim([0 6])
for i = 1:size(a,1)

   line(a(i,[1:2:5,1]), a(i,[2:2:6,2]), 'color',rand(1,3))
   pause;

end
grid on;

Answer 1

a = dlmread('a.txt')
clf

for i = 1:size(a,1)
    line(a(i,[1:2:5,1]), a(i,[2:2:6,2]), 'color',rand(1,3))
end

Notice that I am repeating the vertice to complete the triangle and the I am using a random color each time through the loop.

Because the format is easy, I can use DLMREAD with defaults.