Plot values on a x-y plane from excel - with colorbar

I would like to plot a x-y values from the excel attached on a plane.

I need a colorbar and Latex font.

Thanks everyone!

[Francesco Marchione]

with a bicubic interpolation between values

Answer 1

[Harsh]

Hi @Francesco Marchione,

From what can be gathered, you are trying to plot x and y coordinates using the points mentioned in the Excel file along with a bicubic interpolation between values. Here’s how to do it along with adding a relevant colormap:

T = readtable("Values.xlsx");
x = T.x
y = T.y
z = T.value 
% Create a grid for interpolation
[Xq, Yq] = meshgrid(linspace(min(x), max(x), 100), linspace(min(y), max(y), 100));

% Interpolate z values on the grid
Zq = griddata(x, y, z, Xq, Yq, 'cubic');

% Create the surface plot
figure;
surf(Xq, Yq, Zq, 'EdgeColor', 'none');

% Add colorbar
colorbar;

% Set colormap
colormap jet;

% Set LaTeX font for axes labels and title
xlabel('X-axis', 'Interpreter', 'latex');
ylabel('Y-axis', 'Interpreter', 'latex');
zlabel('Z-axis', 'Interpreter', 'latex');
title('Sample 3D Surface Plot with Bicubic Interpolation', 'Interpreter', 'latex');

% Optionally, set LaTeX font for ticks
set(gca, 'TickLabelInterpreter', 'latex');

Here’s the expected result:

I hope this helps, thanks!

[Francesco Marchione]

I would like to have a top view (I.e., a plane figure, a 2D view)

[Harsh]

@Francesco Marchione, you can do that using the "imagesc" function, here's the updated snippet of code for the same:

% Create a grid for interpolation
[Xq, Yq] = meshgrid(linspace(min(x), max(x), 100), linspace(min(y), max(y), 100));

% Interpolate z values on the grid
Zq = griddata(x, y, z, Xq, Yq, 'cubic');

% Create the 2D plot using imagesc
figure;
imagesc(linspace(min(x), max(x), 100), linspace(min(y), max(y), 100), Zq);
axis xy; % Ensure the y-axis is oriented correctly

% Add colorbar
colorbar;

% Set colormap
colormap jet;

% Set LaTeX font for axes labels and title
xlabel('X-axis', 'Interpreter', 'latex');
ylabel('Y-axis', 'Interpreter', 'latex');
title('Sample 2D Plot with Bicubic Interpolation', 'Interpreter', 'latex');

% Optionally, set LaTeX font for ticks
set(gca, 'TickLabelInterpreter', 'latex');

Here, I have attached the expected result:

To learn more about the "imagesc" function feel free to checkout the following documentation:

https://www.mathworks.com/help/matlab/ref/imagesc.html

[Francesco Marchione]

Thank you so much!