How to extract data from two separate tabs

I have heart rate and time in two columns. I am going to filter heart rates above 95 bpm. However, in another two columns I have certain "events" that occurred throughout the recording and the times the events occurred. The time of the events don't necessarily match up with the time of the heart rates I want to extract. Tips on creating a script to filter out the heart rates above 95 along with the event that precedes the high heart rate??

Answer 1

[Matt Gaidica]

The easiest way to think about this would be using a simple series find statements and the returned indexes to do time comparisons, as well as pull event type.

Post a sample of your actual data, I can imagine some caveats and best practices depending on how it's formatted.

[Sam]

Hi Matt, thank you so much. I'm very new to matlab so I'm sure there is probably a better way to display the data but I imported this from excel and it contains the event times, event codes, heart rate times, and instantaneous frequency (which is heart rate). There are not nearly as many events/event times as there are heart rate data

[Matt Gaidica]

I think either attaching the spreadsheet or getting it into MATLAB is a good start—you can use readtable. I'm happy to illustrate some code if you attach your spreadsheet (I work in physiology as well!).

[Sam]

Thanks for the guidance. I attached the file below in case you have any more thoughts. My goal is to filter out heart rates above 95, just for this particular exampmle, and then the event codes/times that precede it. I appreciate the help! I tried the tutorials, but I wasn't sure how to get started. Anyway thanks

[Matt Gaidica]

Sure thing. Try this:

hrIds = find(Data{:,'Heart Rate'} > 95);
hrTimes = Data{hrIds,'Heart Rate Times'};

eventCodes = NaN(1,numel(hrTimes));
for ii = 1:numel(hrTimes)
    precTimeId = find(Data{:,'Event Times'} < hrTimes(ii),1,'last');
    if ~isempty(precTimeId)
        eventCodes(ii) = Data{precTimeId,'Event Code'};
    end
end

You have some heart rate times that come before the first event, so those are left as NaN.