Can this for-loop be vectorized?

I want to find the moments of footfalls on a forceplate. I first find the peaks in the GRF, and all the valleys in between each step:

[~,locs]=findpeaks(f,'minpeakheight',1000,'minpeakdistance',50);
[~,locs2]=findpeaks(-f,'minpeakheight',-10);

Now I find the last valley before each peak, in order to determine when the force peak of a foot step starts.

for i = 2 : length(locs) - 1
    steps(i-1) = max( locs2(locs2>locs(i-1) & locs2<locs(i)) );
end

Is it possible to change this loop into (short) vectorized code? I have to run this loop often, which takes time.

Thanks!

Answer 1

[Bruno Luong]

u = setdiff(locs2,locs);
% if locs2 is sorted and does not intersect with locs
% you can replace u by locs2
steps = interp1(u,u,locs(2:end-1),'previous')

[Niek Blikslager]

Thank you! This is very usefull