There are multiple ways to do this. Here I show how to put your (x,y,z) coordinates into a timeseries and use resample to interpolate the 3D coordinates.
Main functions
Create an mx3 matrix of [x,y,z] coordinates
xyz is the only input in this demo. The rest of the demo can be copy-pasted.
th = linspace(0,31.5,50)';
xyz = [sin(th),cos(th),th];
Create a timeseries object at 2-minute intervals and interpolate at 60-sec intervals
Create an mx1 vector of time stamps at 2-minute intervals
timestamps = (0:2:size(xyz,1)*2-1)';
Create a timeseries object
ts = timeseries(xyz, timestamps, 'Name', 'XYZdata');
ts.TimeInfo.Units = 'Minutes';
Create an nx1 vector of time stamps at 1-second resolution. The vector spans the range of timestamps in your raw-data.
timestampsInterp = ts.Time(1) : 1/60 : ts.Time(end);
Interpolate, or resample at the new timestamps created above. Interpolation is linear by default; see the timeseries interpolation method in ts.DataInfo.Interpolation. See other interpolation options in resample>interpmethod and timeseries>DataInfo. tsInt = resample(ts,timestampsInterp);
Extract the interpolated xyz data to an nx3 matrix (xyzInt). Note that this step could be skipped and you could work with the interpolated timeseries object directly.
Plot the original and interpolated data
If you're planning on plotting your data, you may want to plot a subsection of the data since it is much larger than these demo data and will take a long time to render and will comsume much memory.
plot3(xyz(:,1),xyz(:,2),xyz(:,3),'bo','LineWidth',2,'DisplayName','Original (2-min)')
plot3(xyzInt(:,1),xyzInt(:,2),xyzInt(:,3),'r.','MarkerSize',3,'DisplayName','Interpolated (1-sec)')
legend('Location','SouthOutside')
Store the new interpolated data in a timetable
This, of course, is optional but it will be useful if you're planning on doing further time-based analysis.
TT = array2timetable(tsInt.Data,...
'RowTimes',seconds(tsInt.Time*60), ...
'VariableNames', {'x','y','z'});
head(TT)
ans =
Time x y z
_____ _________ _______ _________
0 sec 0 1 0
1 sec 0.0049957 0.99834 0.0053571
2 sec 0.0099914 0.99667 0.010714
3 sec 0.014987 0.99501 0.016071
4 sec 0.019983 0.99335 0.021429
5 sec 0.024979 0.99168 0.026786
6 sec 0.029974 0.99002 0.032143
7 sec 0.03497 0.98836 0.0375
