how to plot using the slice function the last row and column of a 3 matrix?

Hello, guys

I am trying to do the slicing of a 3d matrix, however I notice that the slice function during the plot do not show us the last column and row as we can see in the following code:

Is there a way to plot all the value of a 3 matrix during the slicing?

Thank you

Best regards

code:

clear all
clc
a=randi(5,3,3,3);
slice(a,1,[ ],[ ])

[Adam Danz]

I updated your question to format and run your code to show the results.

Answer 1

[Adam Danz]

The syntax slice(V,xslice,yslice,zslice) plots surface using the vertex data in V at slices specifed by the 2nd, 3rd, and 4th arguments. Vertices define the edges of each face. Along a single dimension, a single face has two vertices so along a single dimension you will have a number of face equal to one minus the number of vertices.

Take this reproducible example that plots the faces of a 4x4x4 array along the first slice of the x-axis. It also adds a colorbar so we can see how the data maps to the colors.

rng(6) % for reproducibility
a=randi(5,4,4,4);
slice(a,1,[ ],[ ])
colormap(jet(10))
colorbar

The colors in the bottom row of the surface are defined by

a(:,1,1)

ans = 4×1

5 2 5 1

where 5 is red, 2 is blue, 5 is red, and the next face, if there was one, would be dark blue.

The colors in the middle row of the surface are defined by

a(:,1,2)

ans = 4×1

5 3 5 5

where 5 is red, 3 is mint green, 5 is red, and the next face, if there was one, would be red.

The colors at the top row of the surface are defined by

a(:,1,3)

ans = 4×1

2 4 3 4

where 2 is blue, 4 is yello, 3 is mint green, and the next face, if there was one, would be yellow.

In summary, the plot is produced again below and the vertices of the bottom row are numbered. If you interpolate the FaceColor, you can see the last edge of the vertices effet the colors.

figure
tiledlayout(1,2)
nexttile()
slice(a,1,[ ],[ ])
colormap(jet(10))
colorbar
text([1 1 1 1]-.2, [1 2 3 4], [1 1 1 1], string([1,2,3,4]),'FontSize', 14)
axis square
title('Flat')

nexttile()
h = slice(a,1,[ ],[ ]);
h.FaceColor = 'interp';
colormap(jet(10))
axis square
title('Interpolated')

[Rabih Sokhen]

dear Adam Danz

thank you for you respons.

i would like to plot all the pixel of a specific slice, during witch i will able to see all the pixel.

for the folowing code:

a=randi(5,3,3,3);

% a is a 3*3 matrix and i want to see 9 pixel for a specific slice but i am getting 4 pixel.

how can i plot all 9 pixel for "a" will using :

slice(a,1,[ ],[ ])

thank you

[Adam Danz]

You'll either need to pad your array or you can slice it yourself and user imagesc or heatmap

 a=randi(5,3,3,3);
 m = squeeze(a(1,:,:)); 
 heatmap(m)
 colormap(jet)

[Rabih Sokhen]

hi Adam

"I tried to write the following code, but when I attempt to slice in two directions simultaneously - along both the x and y axes - the resulting values for the x and y axes are not between -1 and 1. Do you have any ideas on how to fix this?"

thank you in advance

code:

clear all

clc

a= randi(2,3,4,5)

x=linspace(-1,1,size(a,1));

y=linspace(-1,1,size(a,2));

z=linspace(-1,1,size(a,3));

slice_3D(x,y,z,a,[],[],z)

colorbar

caxis([1 2])

colormap(jet(2))

function slice_3D(varargin)

if numel(varargin) == 4

[a, x_slice, y_slice, z_slice] = deal(varargin{1:4});

a(end+1,:,:)=nan;

a(:,end+1,:)=nan;

a(:,:,end+1)=nan;

x=linspace(1-0.5,size(a,1)-0.5,size(a,1));

y=linspace(1-0.5,size(a,2)-0.5,size(a,2));

z=linspace(1-0.5,size(a,3)-0.5,size(a,3));

hh=slice(x,y,z,permute(a,[2,1,3]),x_slice,y_slice,z_slice);

set(hh,'EdgeColor','none','FaceAlpha',1);

xlabel('x');

ylabel('y');

zlabel('z');

elseif numel(varargin) == 7

[x ,y ,z, a, x_slice, y_slice, z_slice] = deal(varargin{1:7});

dx=x(2)-x(1);

dy=y(2)-y(1);

dz=z(2)-z(1);

a(end+1,:,:)=nan;

a(:,end+1,:)=nan;

a(:,:,end+1)=nan;

if(isempty(z_slice)~=1 && isempty(y_slice)~=0 && isempty(x_slice)~=0)

x=linspace(x(1),x(end),size(a,1));

y=linspace(y(1),y(end),size(a,2));

z=linspace(z(1),z(end)+dz,size(a,3));

end

if(isempty(y_slice)~=1 && isempty(x_slice)~=0 && isempty(z_slice)~=0)

x=linspace(x(1),x(end),size(a,1));

y=linspace(y(1),y(end)+dy,size(a,2));

z=linspace(z(1),z(end),size(a,3));

end

if(isempty(x_slice)~=1 && isempty(y_slice)~=0 && isempty(z_slice)~=0)

x=linspace(x(1),x(end)+dx,size(a,1));

y=linspace(y(1),y(end),size(a,2));

z=linspace(z(1),z(end),size(a,3));

end

hh=slice(x,y,z,permute(a,[2,1,3]),x_slice,y_slice,z_slice);

set(hh,'EdgeColor','none','FaceAlpha',1);

xlabel('x');

ylabel('y');

zlabel('z');

else

error('IMG: incorrect number of arguments')

end

view(-25,20)

end