How to find start and end points of non-zero elements in a vector

I have some vectors with mostly zeros and a few non-zero values all grouped together (see example plot). I want to know the index for the start and end points of these non-zero areas, i.e. the start and end of the peaks on the plot.

I can use find to get the non-zero areas, then iterate through with a loop to find everywhere the jump in values is greater than 1, but is there a better way to do this?

Answer 1

[Walter Roberson]

t = YourVec ~= 0;
findstr([0 t], [0 1])-1  %gives indices of beginning of groups
findstr([t 0], [1 0])    %gives indices of end of groups

[Eoin Horgan]

Thanks, much better than what i was doing.

[Amrit Zoad]

Thanks Walter! I am in a similar situation but I want to find the center value of the non-zero group of points.

[Walter Roberson]

mask = logical(YourVector(:).');    %(:).' to force row vector
starts = strfind([false, mask], [0 1]);
stops = strfind([mask, false], [1 0]);
centers = mean([starts;stops]);