Determine the start and end of a vector.
20 vues (au cours des 30 derniers jours)
Afficher commentaires plus anciens
When the variable starts incrementing above a threshold, that index is to be determined and also when the same variable starts decrementing below a certain threshold, the index is to be determined.
2 commentaires
Réponse acceptée
Image Analyst
le 28 Sep 2016
Try using diff() and strfind():
% Create random sample data.
v = randi(9, 1, 20)
thresh = 3; % Define the threshold.
% Find indexes where v is at or above the threshold.
d = (v>=thresh)
% Find the starting index where the signal starts above the threshold
% and then starts to fall below the threshold.
fallsBelow = strfind(d, [1, 0])
% Find the starting index where the signal starts below the threshold
% and then starts to rise above the threshold.
risesAbove = strfind(d, [0, 1])
2 commentaires
Walter Roberson
le 28 Sep 2016
This is a good approach when the thresholds are the same. Matters get more complicated when the thresholds are different. For example if you wanted to trigger at 1/4 Volt and to keep monitoring until you dropped to 0 V, then it becomes trickier.
Plus de réponses (0)
Voir également
Catégories
En savoir plus sur Operators and Elementary Operations dans Help Center et File Exchange
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!