Hello Ara
To plot GPS time in both Universal Time (UT) and Local Time (LT), you need to convert the GPS time to hours and then adjust for the local time zone difference from UT. MATLAB makes these conversions straightforward.
I am assuming you have a vector of GPS times in seconds and want to plot some corresponding data, here's how you could do it:
- Convert GPS Time to Hours
First, convert your GPS time from seconds to hours to make it easier to plot on a 0-24 hour scale.
gpsTimeSeconds = ...; % Your GPS time data here
gpsTimeHours = gpsTimeSeconds / 3600; % Convert seconds to hours
2. Adjust for Local Time
Determine the offset of your local time zone from UT. For example, if you are in Eastern Daylight Time (EDT), the offset is -4 hours from UT.
localTimeOffset = -4; % Example for EDT
localTimeHours = gpsTimeHours + localTimeOffset;
% Handle wrapping around 24 hours
localTimeHours = mod(localTimeHours, 24);
3. Plotting
Now, you can plot your data against both UT and LT. Assuming you have a vector `data` that corresponds to the measurements taken at the GPS times:
data = ...; % Your data corresponding to the GPS times
% Plot UT
subplot(2, 1, 1); % Create a subplot for UT
plot(gpsTimeHours, data);
xlabel('Time (UT)');
ylabel('Measurement');
title('Measurement vs. Universal Time');
xlim([0, 24]);
grid on;
% Plot LT
subplot(2, 1, 2); % Create a subplot for LT
plot(localTimeHours, data);
xlabel(['Time (LT, offset ' num2str(localTimeOffset) ' hrs)']);
ylabel('Measurement');
title('Measurement vs. Local Time');
xlim([0, 24]);
grid on;
This code will generate a figure with two subplots: one plotting your data against Universal Time and the other against Local Time.
