There might be an issue with how you're indexing the table or filtering duplicates, other than that, your code seems right to me.
As an alternative, you can use the 'splitapply' function. Take the help of the below mentioned code.
% Assuming your table is named 'raw' with columns 'UTCTime' and 'Svid'
t1 = raw.UTCTime(1);
t2 = raw.UTCTime(end);
t = (t1:seconds(1):t2)';
%Storing the resulting count in num_sats_gps
num_sats_gps = splitapply(@(x) numel(unique(x)), raw.Svid, discretize(raw.UTCTime, t));
%Using 'discretize' function to divide the time range into one-second intervals
The splitapply function applies the anonymous function @(x) numel(unique(x)) to each group of satellite IDs (x) associated with a specific time interval. It counts the number of unique satellite IDs in each group.
Hope this helps.
