Data filtering one-second averages

I have a data set that is collected at about 6.5hz. In the processing of the data, I put the data into Excel and just do a 3 second running average for the entire data set to smooth out the data. Next I would like for a Matlab program to just pick one point per second. I was thinking it could be the first data point each second. For example, if the times for the first second are 1.088, 1.242. 1.398, 1.553, 1.706, and 1.863, I would just want to pull the row of data at 1.088 and output it into a new a variable.

What would be the best way to go about doing this. If there's code to automate the 3 second running average (about 20 lines in excel), that'd be awesome too. Thanks!

[Chad Wiggins]

A sample of this data looks as follows

[Azzi Abdelmalek]

The question is not clear, can you illustrate with an example?

[Chad Wiggins]

Pretty much, I just want to pull one line of data each second. In the case above, I would want it to have the line where time = 0, 1.088, 2.020, 3.103, 4.033, and 5.12

This will just downsample the data and make it easier to work with and do different analysis with.

Help a little?

Answer 1

[MHN]

Load your data in a matrix which the name is Data, then

EndSecond = 3;
NewData = zeros(EndSecond+1,5);
for i = 0:EndSecond
    ind = find(Data>=i & Data<i+1,1,'first');
    NewData(i+1,:) = Data(ind, :);
end

[Chad Wiggins]

Thank you. This works. Only issue is that it throws an error (Improper assignment with rectangular empty matrix.) after the line with NewData(i+1,:) = Data(ind, :);

The NewData variable looks to be correct. Will this prevent me from putting any other commands after this though?

[Chad Wiggins]

Only change you need to make is to add in the first line of the for-loop statement. must add a "-1" to keep from getting an error

for i= 0:EndSecond-1