Averaging values in column 2 if column 1 falls within a certain range
2 vues (au cours des 30 derniers jours)
Afficher commentaires plus anciens
Hi,
I am pretty stuck and would really appreciate some/any help or a push in the right direction.
I have matrix "B" which has time(sec) in column 1 and Diameter in column 2.
I am trying to do something like this:
If column 1 is between n and n+0.99 seconds, average all the value in column 2 and also indicate what value 'n' was in the column next to it. Repeat this for n+1 all the way to the end.
so the intervals will be 1 - 1.99 , 2 - 2.999 , 3 - 3.99 all the way to 60 seconds.
![](https://www.mathworks.com/matlabcentral/answers/uploaded_files/221678/image.jpeg)
Thank you,
Nev
0 commentaires
Réponse acceptée
Alex Mcaulley
le 29 Mai 2019
Try this (just changing by your real B):
n = 1:60;
B = rand(1000,2);
B(:,1) = linspace(1,60,1000);
means = arrayfun(@(i) mean(B(B(:,1)>=n(i)&B(:,1)<n(i+1),2)),1:(numel(n)-1));
Nextn = B(arrayfun(@(i) find(B(:,1)>=n(i)&B(:,1)<n(i+1),1,'last'),1:(numel(n)-1))+1,1);
6 commentaires
Alex Mcaulley
le 30 Mai 2019
Yes, this line:
B(:,1) = linspace(1,60,7841);
was just for my example data. The correct code is
n = 1:60;
means = arrayfun(@(i) mean(B(B(:,1)>=n(i)&B(:,1)<n(i+1),2)),1:(numel(n)-1));
Nextn = B(arrayfun(@(i) find(B(:,1)>=n(i)&B(:,1)<n(i+1),1,'last'),1:(numel(n)-1))+1,1);
Plus de réponses (1)
Steven Lord
le 30 Mai 2019
I would use groupsummary specifying the groupbins input as either a list of bin edges or (if you can convert your time data to a duration array) 'second' and the method as 'mean'.
Voir également
Catégories
En savoir plus sur Performance and Memory 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!