How to get a window of signal data before and after its peak?
I have a 2 column array. It represents an exponential rise/fall of voltage and the time for each datapoint. In the voltage, I want to locate the data in a window between the first time the voltage exceeds 0.2*Vpeak up to when it falls below 0.4*Vpeak. The values before and after the window are then to be replaced with zeros.
Kshitij Singh answered .
2025-11-20
>> [pks, locs] = findpeaks(voltage);
Then, from all the peaks, determine the global peak:
>> [vPeak, iPeak] = max(pks); >> locPeak = locs(iPeak);
Finally, use the "find" function to find the indices of when your signal reaches 0.2*Vpeak and drops to 0.4*Vpeak of its peak:
>> idx_start = find(voltage(1:locPeak) < 0.2*vPeak, 1, 'last'); >> idx_end = locPeak + find(voltage(locPeak:end) < 0.4*vPeak, 1, 'first');