How to label your peaks in descending order?

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John Mark Enhaynes on 30 Mar 2021
Edited: LO on 30 Mar 2021
I search the whole community and website on how to label my peaks from 1-5 from the highest value given
Here is my code I've made so far:
fid=fopen('Programming 2 Data.txt');
f=cell2mat(e);
x = f(:,1);
y = f(:,2);
[sortedX,sortIndex]=sort(x);
sortedY=y(sortIndex);
plot(x,y)
findpeaks(sortedY,sortedX,'MinPeakHeight',290,'Annotate','Extents');
xlabel('cm^-1')
ylabel('%T')
title('FTIR')
axis tight
grid
set(gca,'xdir','reverse')
I have search the terminology on findpeaks, but it doesn't really help me that much to get the desired result that I wanted.
3 CommentsShow 1 older commentHide 1 older comment
John Mark Enhaynes on 30 Mar 2021
I've tried that, but I've got similar errors from other users I've seen in the forum
Mathieu NOE on 30 Mar 2021
I ve plenty of other similar functions (attached)
try with peakseek and do the sorting by yourself afterwards

LO on 30 Mar 2021
Edited: LO on 30 Mar 2021
something like this ?
my guess is that you won't need the sortedX because you are looking for peaks on your Y axis, right ? But try adapting this to your code. Eventually the "locs" variable will have to be modified taking into account your X vector.
[peaks,locs,widths] = findpeaks(sortedY,'MinPeakHeight',290,'Annotate','Extents');
[vals,order] = sortrows(peaks,'descend'); % sort them based on peak value, for instance, but you can sort them based on widths as well (just replace peaks with widths in sortrows)
scatter(locs(order),peaks(order),'rv');