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Topic: plot a 3D graph
Replies: 2   Last Post: Feb 27, 2013 12:45 PM

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 Toan Cao Posts: 55 Registered: 10/15/10
Re: plot a 3D graph
Posted: Feb 27, 2013 12:45 PM

> try this:
>
> function gplot4(A, xyz)
> % GPLOT3(A, xyz) is nearly the same as GPLOT(A, xy) except
> % that the xyz variable requires a third dimension.
> % This function takes an adjacency matrix and visualizes it
> % in 3D.
> [d e] = size(A);
> if d ~= e
> error('A matrix must be square.');
> end
>
> [points f] = size(xyz);
> if f ~= 3
> error('xyz matrix must be of width 3');
> end
>
> if points ~= d
> error('Width of A must equal height of xyz.');
> end
>
> xp = [];
> xq = [];
> yp = [];
> yq = [];
> zp = [];
> zq = [];
> % c = [];
>
>
> for i = 1:(d-1)
> for j = 2:d
> if A(i,j) ~= 0
> xp = [xp xyz(i, 1)];
> xq = [xq xyz(j, 1)];
> yp = [yp xyz(i, 2)];
> yq = [yq xyz(j, 2)];
> zp = [zp xyz(i, 3)];
> zq = [zq xyz(j, 3)];
> % c = [c full(A(i,j))];
> end
> end
> end
> line([xp; xq], [yp; yq], [zp; zq]);
> %
> %
> % numc = 10;
> % cmap = autumn(numc);
> %
> % c = (c - min(c))/(max(c)-min(c));
> % c = floor((c*(numc-1))+1);
> % %c = cmap(c,:);
> % % line([xp; xq], [yp; yq], [zp; zq]);
> %
> % for n = 1:numel(xp)
> % line([xp(n); xq(n)], [yp(n); yq(n)], [zp(n); zq(n)],'Color',cmap(c(n),:));
> % end
> %
> end
>
> Am Dienstag, 19. Februar 2013 22:40:20 UTC+1 schrieb Toan Cao:

> > Hi everyone,
> >
> >
> >
> > I make a 3D graph of N nodes (vertices of 3D point cloud). I also have an adjacency matrix A (its size: NxN) for this graph where A(i,j)=1 if node i and node j connect together. If not , A(i,j)=0.
> >
> > So, i want to display this graph in 3D where two nodes (i, j) are linked by a line if A(i, j)=1.
> >
> > I know there is a function "gplot" for 2D graph, but i can not find the one for 3D graph.
> >
> > Do you know how to display my graph in 3D? Hope to get your help!
> >
> >
> >
> >
> > Toan

Thank you so much for your method
I will try to apply it in my case.

Toan

Date Subject Author
2/19/13 Toan Cao
2/27/13 Toan Cao