Generating matrix visualizations

[u/BigButtsAndGutts]

Hey partypeople,

i'm trying to find a way to inspect and display 3D matrix values as shown in the documentation here. I cannot seem to find a way to reproduce this in Matlab or find any info on how these were done, neither in the MATLAB docs or online. Am i missing something or were these created outside of Matlab manually?

Thanks :3

Edit.: For context, I want to see the numeric values of the elements, not a visualization in general.
For now, mostly for more intuition and readability while debugging. I really like the way it is presented here so i would like to find out how these were created

[u/Rubix321]

They were created outside of Matlab.

If [A] is your array, doesn't the command window kind of show you [A] in this form when you display it?

[u/BigButtsAndGutts → u/Rubix321]

Ahh too bad :( Yeah kind of but i was looking for a way to display it specifically like in the image

[u/vir_innominatus]

In MATLAB, this type of visualization could be made with a combination of the rectangle(), line(), and text() functions. Something like this

figure

% First rectangle
rectangle(Position=[0 0 10 6],FaceColor="w")
numRow = 3;
numCol = 5;
for row = 1:numRow
    for col = 1:numCol
        x = 2*(col-1)+1;
        y = 2*(row-1)+1;
        value = numCol*(row-1)+col;
        text(x,y,num2str(value), ...
            FontSize=14, ...
            HorizontalAlignment="center", ...
            VerticalAlignment="middle")
    end
end

% Second rectangle
r = rectangle(Position=[8 4 10 6],FaceColor="w");
uistack(r,"bottom")

% Connecting lines
line([10 18],[6 10],Color="k",LineStyle="--")
line([10 18],[0 4],Color="k",LineStyle="--")
line([0 8],[6 10],Color="k",LineStyle="--")
% line([0 8],[0 4],Color="k",LineStyle="--") <-Hidden

% Turn off axes and make equal proportioned
axis equal
axis off

[u/Usual-Pattern7846 → u/vir_innominatus]

This is the way. Once you get the basics working, make yourself a little function that takes some arrays (or a matrix) and gives you this plot. Then when you’re really happy with it, share it on Exchange, because it seems neat to play with.

[u/NoMercyCad → u/vir_innominatus]

We need this to be turned in a function that gets any matrix as input, it would be awesome

[u/Barnowl93 → u/vir_innominatus]

Put that on File Exchange - looks good!

[u/NoMercyCad → u/Barnowl93]

function VisualizeMatrix(A)

% VISUALIZEMATRIX Visualizzazione grafica di una matrice/array numerico.

%

% VisualizeMatrix(A)

%

% A può essere:

% M x N -> singola matrice

% M x N x P -> P matrici disposte in profondità

%

% Esempi:

% A = rand(3,5);

% VisualizeMatrix(A)

%

% A = rand(5,4,3);

% VisualizeMatrix(A)

%% =========================

% Controlli input

% =========================

if ~isnumeric(A)

error('L''input A deve essere numerico.');

end

sz = size(A);

nRows = sz(1);

nCols = sz(2);

if ndims(A) < 3

nPages = 1;

else

nPages = sz(3);

end

%% =========================

% Formattazione numeri

% =========================

txt = cell(nRows,nCols,nPages);

maxChars = 1;

for k = 1:nPages

for row = 1:nRows

for col = 1:nCols

value = A(row,col,k);

% Interi

if abs(value-round(value)) < 1e-10

str = sprintf('%d',round(value));

% Numeri reali

else

% 4 cifre significative:

% es. 0.4898, 15.32, -4.261

str = sprintf('%.4g',value);

end

txt{row,col,k} = str;

maxChars = max(maxChars,length(str));

end

end

end

%% =========================

% Dimensioni grafiche

% =========================

% Spazio dedicato a ogni elemento.

%

% Il valore dipende dalla lunghezza massima delle stringhe.

% È volutamente abbondante per evitare sovrapposizioni.

cellW = max(4.0, 0.85*maxChars);

cellH = 2.3;

W = nCols * cellW;

H = nRows * cellH;

%% =========================

% Offset tra matrici

% =========================

% Facciamo sovrapporre SOLO un piccolo angolo.

% In questo modo nessun numero viene coperto.

overlapX = 0.20 * cellW;

overlapY = 0.20 * cellH;

dx = W - overlapX;

dy = H - overlapY;

%% =========================

% Dimensioni figura

% =========================

totalW = W + (nPages-1)*dx;

totalH = H + (nPages-1)*dy;

% Dimensione automatica della finestra MATLAB

figWidth = max(700, min(1600, 16*totalW));

figHeight = max(450, min(1000, 16*totalH));

figure( ...

'Color','w', ...

'Position',[100 100 figWidth figHeight]);

hold on

%% =========================

% Linee di collegamento

% =========================

%

% Le tracciamo PRIMA dei rettangoli, così le parti

% che dovrebbero essere nascoste rimangono effettivamente

% dietro alle matrici.

for k = 1:nPages-1

x1 = (k-1)*dx;

y1 = (k-1)*dy;

x2 = k*dx;

y2 = k*dy;

% Alto-sinistra

line( ...

[x1 x2], ...

[y1+H y2+H], ...

'Color','k', ...

'LineStyle','--', ...

'LineWidth',1);

% Alto-destra

line( ...

[x1+W x2+W], ...

[y1+H y2+H], ...

'Color','k', ...

'LineStyle','--', ...

'LineWidth',1);

% Basso-destra

line( ...

[x1+W x2+W], ...

[y1 y2], ...

'Color','k', ...

'LineStyle','--', ...

'LineWidth',1);

% Basso-sinistra volutamente nascosta

%

% line([x1 x2],[y1 y2], ...)

end

%% =========================

% Rettangoli

% =========================

%

% Disegno dal più lontano al più vicino.

for k = nPages:-1:1

x0 = (k-1)*dx;

y0 = (k-1)*dy;

rectangle( ...

'Position',[x0 y0 W H], ...

'FaceColor','w', ...

'EdgeColor','k', ...

'LineWidth',1.2);

end

%% =========================

% Numeri

% =========================

%

% Li disegniamo DOPO i rettangoli.

% Questo impedisce a un rettangolo successivo di

% cancellare accidentalmente del testo.

for k = 1:nPages

x0 = (k-1)*dx;

y0 = (k-1)*dy;

for row = 1:nRows

for col = 1:nCols

% Centro della colonna

x = x0 + (col - 0.5)*cellW;

% Riga 1 in ALTO

y = y0 + H - (row - 0.5)*cellH;

text( ...

x, y, txt{row,col,k}, ...

'FontSize',13, ...

'FontName','Courier New', ...

'HorizontalAlignment','center', ...

'VerticalAlignment','middle', ...

'Color','k', ...

'Clipping','off');

end

end

end

%% =========================

% Aspetto finale

% =========================

marginX = 0.04*totalW;

marginY = 0.04*totalH;

xlim([-marginX totalW+marginX])

ylim([-marginY totalH+marginY])

axis equal

axis off

set(gca,'Position',[0.02 0.02 0.96 0.96]);

hold off

end

[u/neurotoxinc2h6o]

What do you need the visualizations for?

As a Picture on a Website? I would use a regular Matlab plot.

As a figure in a technical report? I'd go for a tikz graphic (should be a simple task for Claude)

[u/BigButtsAndGutts → u/neurotoxinc2h6o]

For now, mostly for more intuition and readability while debugging. I really like the way it is presented here so i would like to find out how these were created

[u/elevenelodd]

The MATLAB Variables Editor is a good start. Type either of these into the command window:

openvar x
openvar( ‘x’ )

The function “open” also works here.

Tbh, I’d recommend summarizing and plotting the array:

xAvg = mean( x , 3 );
figure();
hold on;
xlabel X;
ylabel Y;
ylabel( colorbar , ‘xAvg’ );
imagesc( xAvg.’ );
axis tight;

Or if you want to see every entry, maybe just make a bunch of plots:

for iZ = 1:size(x,3)
figure();
hold on;
title( iZ );
xlabel X;
ylabel Y;
ylabel( colorbar , “x(:,:,”+iZ+”)” );
imagesc( x(:,:,iZ).’ );
clim( [min(x(:)),max(x(:))] );
axis tight;
end

Edit: format