Issue with locating end of poorly defined peak
1 visualizzazione (ultimi 30 giorni)
Mostra commenti meno recenti
Teshan Rezel
il 19 Giu 2022
Commentato: Mathieu NOE
il 22 Giu 2022
Hi folks,
I have several graphs that look similar to the one attached. I am trying to formalise a general approach to finding the location of the start and end of each peak. The start is somewhat easy (using find, and the peak position can be found using max), since the graph starts from 0 (I am interested only in the second entry onwards).
However, the end is really tricky as it never quite gets to zero. I have tried using findpeaks, and also myEnd = find(iso(myPeakLoc:end, 1) > 1e-06); but to no avail.
Can someone advise me on an alternative route please?
1 Commento
Risposta accettata
Mathieu NOE
il 20 Giu 2022
hello again
tried this - does it help ?
load('iso.mat')
curve = 10; % which curve do you want to plot ?
data = percent_iso(2:end,curve);
% max point
[maxval,maxind] = max(data);
% start point = find first point above 0.1% of max value
[startind] = find(data>0.001*maxval,1,'first');
startval = data(startind);
% stop point= find first point below 0.1% of max value past the peak
[endind] = find(data(maxind:end)<0.001*maxval,1,'first');
endind = endind + maxind;
endval = data(endind);
plot(data,'DisplayName','percent_iso')
hold on
plot(maxind,maxval,'dr',startind,startval,'dg',endind,endval,'dk');
hold off
legend('data','max','start','end');
2 Commenti
Più risposte (0)
Vedere anche
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!