Contour 3D: how to take Z matrix value?

Hello,

I want to use contour 3D plot command. But anyone can guide me, how I can take Z-axis? i.e. it should be an relation between X and Y (Or expression) would be necessary? I have three single column data (of size 13 x 1). Please provide example, if any.

Answer 1

[Prateekshya]

Hello Dhiraj,

To create a 3D contour plot in MATLAB, you need a grid of Z values that represent the relationship between your and Y data. If you have three single-column datasets (let us call them X, Y, and Z), you can use these to create a 3D contour plot. However, you need to ensure that your data is structured correctly to form a grid.

Steps to Create a 3D Contour Plot

• Prepare Data: Ensure that your X, Y, and Z data can form a grid. If Z is a function of X and Y, you will need to create a meshgrid.
• Use meshgrid: This function helps in creating a grid of and Y values. You can then calculate values for this grid.
• Plot with contour3: Use this function to create a 3D contour plot.

% Example data
X = linspace(-5, 5, 13)';  % Example X data
Y = linspace(-5, 5, 13)';  % Example Y data
Z = sin(sqrt(X.^2 + Y.^2)); % Example Z data as a function of X and Y

% Create a meshgrid
[XGrid, YGrid] = meshgrid(X, Y);

% Calculate Z values for the grid
ZGrid = sin(sqrt(XGrid.^2 + YGrid.^2)); % Replace with your actual Z function

% Plot the 3D contour
figure;
contour3(XGrid, YGrid, ZGrid, 20); % 20 contour levels
xlabel('X-axis');
ylabel('Y-axis');
zlabel('Z-axis');
title('3D Contour Plot');
grid on;

The result of this code is:

I hope this helps!