matrix show , grain boundaries

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HG 2021-5-4

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编辑： Walter Roberson 2023-10-5

采纳的回答： DGM

how can i show a matrix like this photo with black line boundaries ?

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KSSV 2021-5-4

What data you have? You need to have a look on voronoi.

DGM 2021-5-4

If you're going to ask the same question three times, why do you provide even less information now?

https://www.mathworks.com/matlabcentral/answers/817820-show-a-digit-matrix-with-segmentation-line

https://www.mathworks.com/matlabcentral/answers/817800-how-can-i-show-a-matrix-with-the-interface-boundary-or-segmentation-line-between-different-numbers

Now I'm reluctant to even answer it if it's just going to get deleted. If all you have is an indexed image, apply edge finding techniques, combine the images. You can keep it indexed or convert it to RGB. Look up fspecial(), imfilter(), edge(), ind2rgb(), colormap(), imshow().

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DGM 2021-5-5

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编辑：DGM 2021-5-6

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Your prior questions suggest that you already have an image to start with. A crude way to add lines to it is to just use edge finding methods. In this example, I'm just using an RGB image. You can do the same with an indexed image, but if you want it to display neatly with distinct colors, you'll have to figure out a colormap that does so (e.g. colorcube or a custom map).

inpict = imread('vdiag.png'); % this is rgb, uint8
emap = any(edgemap(inpict),3); % find edges
emap(:,[1:3 end-2:end]) = 1; % add border around image
emap([1:3 end-2:end],:) = 1;
% thin the edges and the dilate so it has uniform width
emap = imdilate(bwmorph(emap,'thin','Inf'),ones(3));
outpict = inpict.*uint8(~emap); % make edge regions zero
imshow(outpict) % show it

The function edgemap() is from MIMT:

https://www.mathworks.com/matlabcentral/fileexchange/53786-image-manipulation-toolbox

If you don't want to use that, you can use any other method for edgefinding by gradient approximation. That can be done with fspecial+imfilter and some math, or you can use edge().

emap = zeros(size(inpict));
for c = 1:size(inpict,3)
	emap(:,:,c) = edge(inpict(:,:,c),'sobel');
end
emap = any(emap,3);

Of course, that still requires IPT, where MIMT does not. If IPT is truly an issue, MIMT also has alternatives for imdilate() and bwmorph().

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DGM 2021-6-10

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The MIMT zip file contains (or should contain) all the dependencies like ifversion(). It's possible that you added the MIMT directory to the path, but not its subdirectories. ifversion() is in MIMT/FEX_dependencies/ifversion_fex, so just check to make sure all those subdirectories are included on the path.

There's one other thing that might be causing issues, and that's trying to represent a small array with an equally small image. For the sake of being able to fit lines in between regions, the displayed image might need to be scaled up.

inpict = uint8([ 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1; 
    2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1;
    2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1;
    3 3 3 3 3 3 3 3 3 3 3 3 1 1 1 1 1;
    3 3 3 3 3 3 3 3 5 5 5 5 5 5 5 5 5;
    3 3 3 3 3 3 3 5 5 5 5 5 5 5 5 5 5;
    5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5]);
% the image needs to be big enough that lines can exist between regions
inpict = imresize(inpict,25,'nearest'); % use 'nearest'
% could use this to get the edge map
%emap = any(edgemap(inpict),3);
% or this is the non-MIMT alternative i'd suggested
emap = zeros(size(inpict));
for c = 1:size(inpict,3)
    emap(:,:,c) = edge(inpict(:,:,c),'sobel');
end
emap = any(emap,3);
emap(:,[1:3 end-2:end]) = 1; 
emap([1:3 end-2:end],:) = 1;
emap = imdilate(bwmorph(emap,'thin','Inf'),ones(3));
inpict = ind2rgb(inpict,colorcube);
outpict = inpict.*(~emap);

If that imresize() line is omitted, you'd get this: (scaled up afterwards so it's visible in browser)

As for how to generate initial arrays for different curved-face polygons, that should probably be best asked as a separate question. I don't have any recommended/preferred approaches to that off the top of my head, but I wouldn't doubt that someone else does.

HG 2021-6-11

There are 3 problems:

1- The size of small matrices changes

2- The matrix apparently becomes three-dimensional.

3- I want to use hot colormap so that from the least number to the most number of the matrix is shown with colors in the hot colormap range , i.e, number 1 with black color(hot colormap) and number 5 with white color and others between them base on colormap.

Are these problems solvable?

DGM 2021-6-11

编辑：DGM 2021-6-11

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If there are to be lines drawn between regions, the size of small images must change, otherwise there's nowhere to put the lines. Consider the image [1 1; 2 2; 3 3]. You'd need 4 horizontal lines and 2 vertical lines. That's more pixels than there even are in the image. Even for slightly larger images, the minimal line width would still cover large portions of the regions and distort their apparent geometry.

The output matrix is RGB. That's why it's 3D. You could use a different colormap using ind2rgb() just the same:

% just incorporate the lines into the indexed image
inpict(emap) = max(inpict(:))+1;
inpict = inpict-1; % uint8 indexed images start at 0
% build a custom colormap from hot()
% adjust n as needed for other images
n = 100;
cmap = hot(double(max(inpict(:)))*n+1);
cmap = cmap(1:n:end,:)
outpict = ind2rgb(inpict,cmap);

or you could just leave inpict as an indexed image and have fun dealing with carrying around colormaps if you wanted.

imshow(inpict,cmap);

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Adam Danz 2021-5-4

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编辑：Adam Danz 2021-5-5

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H Ghari > how can i show a matrix like this photo with black line boundaries ?

This should get you started:

rng default;

n = 100;

x = rand([1 n]);

y = rand([1 n]);

h = voronoi(x,y);

DT = delaunayTriangulation(x(:),y(:));

[V,R] = voronoiDiagram(DT);

verts = cell(size(R));

for i = 1:numel(R)

verts{i} = V(R{i}([1:end,1]),:);

end

hold on

axlims = [xlim; ylim]; % [xlim; ylim]

patchColors = hsv(numel(verts)+1);

for j = 1:numel(verts)

patch(verts{j}(:,1), verts{j}(:,2), patchColors(j,:))

end

delete(h)

set(gca,'color', patchColors(end,:)) % <-- kind of cheating

axis equal

xlim(axlims(1,:))

ylim(axlims(2,:))

Also see these two blog posts by Mike Garrity.

And the vononi2mask or the voronoizone functions on the file exchange (not tested).

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ali can kaya 2023-10-5

编辑：Walter Roberson 2023-10-5

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Hi 
Do you knoW hoW can I mesh this data for abaqus?
If you have any idea it would help me alot. I tried here delanuay triangulate but did not work

th = linspace( pi/3.4, -pi/2, 100);
R = 0.25;  %or whatever radius you want
for i=0:0.2:1
    for j=0:0.4:1
        x = R*cos(th)+i ;
        y = R*sin(th)+j ;
        plot (x,y)
        hold on
    end 
end
rng default
x= rand([1 50]);
y= rand([1 50]);
voronoi(x,y)
DT = delaunayTriangulation(x(:),y(:));
[V,R] = voronoiDiagram(DT);
verts = cell(size(R)); 
for i = 1:numel(R)
    verts{i} = V(R{i}([1:end,1]),:); 
end
xlim([0 1.3])
ylim([-0.2 1])