Academic Block

Logo of Academicblock.net
Menu

Advanced Data Plotting in MATLAB

Plots and Visual representation of the data is a core strength of MATLAB, offering extensive tools to display, analyze, and interpret data visually. This section covers the advanced Plotting techniques.

Scatter Plots

% Creating a scatter plot
x = randn(1, 100);
y = randn(1, 100);
scatter(x, y, 'filled'); % Create scatter plot with filled markers
title('Scatter Plot Example');
xlabel('x-axis');
ylabel('y-axis');
grid on;
Image showing Scatter Plot, obtained using Matlab

Pie Charts

% Creating a pie chart
data = [40, 30, 20, 10];
labels = {'A', 'B', 'C', 'D'};
pie(data, labels);
title('Pie Chart Example');
Image showing Pie Chart, obtained using Matlab

Interactive Plot Using plot

The plot function can be made interactive using datacursormode:

% Interactive Line Plot
x = 0:0.1:10;
y = sin(x);
plot(x, y, '-o'); % Plot with markers
title('Interactive Sine Plot');
xlabel('x-axis');
ylabel('y-axis');
grid on; % Enable grid
datacursormode on; % Enable data cursor for interaction
Image showing example of Interactive Plot, obtained using Matlab

Dynamic 3D Rotatable Plot

Users can rotate 3D plots dynamically with the mouse using the rotate3d function:

% Dynamic 3D Plot
[X, Y] = meshgrid(-5:0.1:5, -5:0.1:5);
Z = sin(sqrt(X.^2 + Y.^2));
surf(X, Y, Z); % 3D surface plot
title('Dynamic 3D Surface Plot');
xlabel('X-axis');
ylabel('Y-axis');
zlabel('Z-axis');
colorbar; % Add color scale
rotate3d on; % Enable interactive rotation
Image showing 2 views of 3D Rotatable Plots, obtained using Matlab

Advanced Visualization Examples in Matlab

Heatmaps

Heatmaps are useful for visualizing data matrices:

% Creating a Heatmap
data = rand(10, 10); % Generate random data
heatmap(data); % Create heatmap
title('Heatmap Example'); % Add title
Image showing example of Random Number generated Heatmap, obtained using Matlab

Bubble Charts

Bubble charts allow visualization of three variables in 2D space:

% Creating a Bubble Chart
x = rand(1, 50); % X-coordinates
y = rand(1, 50); % Y-coordinates
sizes = 100 * rand(1, 50); % Bubble sizes
bubblechart(x, y, sizes); % Generate bubble chart
title('Bubble Chart Example');
xlabel('x-axis');
ylabel('y-axis');
Image showing Bubble Chart, obtained using Matlab

Geographical Plots

MATLAB supports geographic visualizations:

% Creating a Geographical Plot
lat = [37.7749, 34.0522, 40.7128]; % Latitude of cities
lon = [-122.4194, -118.2437, -74.0060]; % Longitude of cities
names = {'San Francisco', 'Los Angeles', 'New York'};
geobasemap('streets'); % Set map style
geoplot(lat, lon, '-o', 'LineWidth', 2); % Plot on map
text(lat, lon, names, 'VerticalAlignment', 'bottom'); % Add labels
title('Geographical Plot Example');
Image showing latitude and longitude based Geographical Plot, obtained using Matlab

Animations

Animations make data presentations more dynamic and intuitive:

% Creating an Animation
x = 0:0.1:10;
y = sin(x);
figure; % Create a figure window
h = plot(x(1), y(1), '-o'); % Initialize plot
xlim([0, 10]); % Set x-axis limits
ylim([-1, 1]); % Set y-axis limits
title('Sine Wave Animation');
xlabel('x-axis');
ylabel('y-axis');
for i = 2:length(x)
set(h, 'XData', x(1:i), 'YData', y(1:i)); % Update plot
pause(0.1); % Pause for smooth animation
end

Useful MATLAB Functions for Advanced Visualization

Function
Explanation
pie
Creates pie charts.
datacursormode
Enables interactive data cursor functionality.
rotate3d
Allows rotation of 3D plots with the mouse.
heatmap
Generates a heatmap visualization of a data matrix.
bubblechart
Creates bubble charts for 2D data with variable bubble sizes.
geoplot
Plots data on a geographical map.
pause
Introduces a delay in animations.

Practice Questions

Test Yourself

1. Generate a 3D plot for Z = cos(X^2 + Y^2).

2. Visualize a data matrix using a heatmap and interpret the results.

3. Generate an animation for a cosine wave.

4. Plot a geographical map of three cities with labeled coordinates.