Import Data with Headers and Plot on a Plane

The standard way to load tabular files (CSV, TXT, Excel) containing column headers in MATLAB is using readtable(). This automatically preserves header names as variable properties.

1. Sample Data Creation (for Testing)

Run this snippet to create a test file named sensor_data.csv with header labels:

% Create sample table with headers
Time_sec  = (0:0.1:10)';
Position_X = 2 * sin(Time_sec);
Position_Y = 3 * cos(Time_sec);

T_sample = table(Time_sec, Position_X, Position_Y);
writetable(T_sample, 'sensor_data.csv');

2. Import Data and Plot on a 2D Plane (X-Y Plane)

Read the table and reference columns directly by their header names with dot notation (data.HeaderName).

% Import CSV or Excel file with headers
data = readtable('sensor_data.csv');

% Display the first 5 rows and column names
head(data, 5)
% Plot Position_X vs Position_Y on a 2D plane
figure('Color', 'w');
plot(data.Position_X, data.Position_Y, 'b-o', ...
    'LineWidth', 1.5, ...
    'MarkerSize', 4, ...
    'MarkerFaceColor', [0.2 0.6 0.9]);
% Set labels dynamically using table variable names
xlabel(data.Properties.VariableNames{2}, 'Interpreter', 'none');
ylabel(data.Properties.VariableNames{3}, 'Interpreter', 'none');
title('2D Plane Trajectory (Position_X vs Position_Y)');
grid on;
axis equal; % Maintain true aspect ratio

3. Plotting 3D Data Projected onto a Plane

To plot 3D coordinates and project them onto a 2D plane, use plot3() with view() or add drop lines to the baseline plane.

figure('Color', 'w');

% 3D trajectory
plot3(data.Time_sec, data.Position_X, data.Position_Y, 'r-', 'LineWidth', 1.5);
hold on;
% Add reference shadow projection on the bottom plane (Z = min)
z_floor = min(data.Position_Y) * ones(size(data.Position_Y));
plot3(data.Time_sec, data.Position_X, z_floor, 'Color', [0.7 0.7 0.7], 'LineStyle', '--');
xlabel('Time (s)');
ylabel('Position X');
zlabel('Position Y');
title('Trajectory with Plane Projection');
grid on;
view(45, 30); % Set 3D perspective

4. Import Options: Converting Headers to Matrix Directly

If you prefer numeric arrays rather than tables, skip the header row during import with readmatrix():

% Reads data starting below row 1
M = readmatrix('sensor_data.csv', 'NumHeaderLines', 1);

posX = M(:, 2);
posY = M(:, 3);
figure('Color', 'w');
scatter(posX, posY, 25, 'filled');
xlabel('X Position');
ylabel('Y Position');
grid on;