Colormap and colorbar in MATLAB - Mini Project: Build & Apply

Colormap and Colorbar in MATLAB

📖 Scenario: You are working with a heatmap to visualize temperature data across a grid. You want to use colors to show different temperature levels clearly.

🎯 Goal: Create a matrix of temperature data, apply a colormap to show temperature variations, and add a colorbar to explain the colors.

📋 What You'll Learn

Create a 5x5 matrix called temperature with specific values

Define a colormap variable called myColormap using the jet colormap

Apply the colormap to the heatmap plot

Add a colorbar to the plot

💡 Why This Matters

🌍 Real World

Scientists and engineers often use heatmaps with colormaps and colorbars to visualize temperature, pressure, or other measurements across areas.

💼 Career

Knowing how to use colormaps and colorbars helps in data visualization tasks common in research, engineering, and data analysis jobs.

1

Create the temperature data matrix

Create a 5x5 matrix called temperature with these exact values: [15 18 21 24 27; 16 19 22 25 28; 17 20 23 26 29; 18 21 24 27 30; 19 22 25 28 31]

MATLAB

% Create the 5x5 matrix called temperature
% Your code here

Need a hint?

Use square brackets to create the matrix and separate rows with semicolons.

2

Define the colormap

Create a variable called myColormap and set it to the jet colormap with 64 colors by writing myColormap = jet(64);

MATLAB

temperature = [15 18 21 24 27; 16 19 22 25 28; 17 20 23 26 29; 18 21 24 27 30; 19 22 25 28 31];
% Define the colormap variable myColormap
% Your code here

Need a hint?

Use the jet function with the number 64 inside parentheses.

3

Plot the heatmap and apply the colormap

Use imagesc(temperature) to plot the matrix and then apply the colormap by writing colormap(myColormap)

MATLAB

temperature = [15 18 21 24 27; 16 19 22 25 28; 17 20 23 26 29; 18 21 24 27 30; 19 22 25 28 31];
myColormap = jet(64);
% Plot the temperature matrix as a heatmap
% Apply the colormap
% Your code here

Need a hint?

Use imagesc to show the matrix as colors, then colormap to set the colors.

4

Add a colorbar to explain the colors

Add a colorbar to the plot by writing colorbar and then display the figure

MATLAB

temperature = [15 18 21 24 27; 16 19 22 25 28; 17 20 23 26 29; 18 21 24 27 30; 19 22 25 28 31];
myColormap = jet(64);
imagesc(temperature);
colormap(myColormap);
% Add a colorbar to the plot
% Your code here

Need a hint?

Just write colorbar to add the color scale next to the heatmap.