How to find index of continous non-NaN values?

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Hi, I want to find index of continuous non-NaN values in a row of a matrix. In the attached file, maximum non-NaN data value block is 600 which is at the end of the array. I want to find start and end of this block of max continuous non-NaN data values.
I used following code from this link,
D = diff([false,~isnan(Sal),false]);
L = find(D<0)-find(D>0) ;
I need help to get the start and end index of such block from an array with maximum data values if such block of continuous value is in the middle of an array.
My goal is to use this block for spectral analysis. Hence, I need continuous data values. Also, the data is discontinuous sometimes, so I am trying to just use the bigger block of continuous values.
Please forgive my errors in framing the problem.
Thank you.

Accepted Answer

Walter Roberson
Walter Roberson on 24 Jan 2022
mask = ~isnan(Sal(:).'); %row vector needed
starts = strfind([false mask], [false true]);
stops = strfind([mask false], [true false]);
Now Sal(starts(K):stops(K)) is a block of consecutive non-nan values.
  4 Comments
Dolly More
Dolly More on 25 Jan 2022
Okay. I used following code to pick one pair of index.
Df = stops - starts;
mx= find(Df==max(Df));
Sal(starts(mx)+1:stops(mx))
Walter Roberson
Walter Roberson on 25 Jan 2022
that will not work if there are two blocks each maximum length, whereas the max() call I showed would work in that case.

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