- column 1 of xab is less than 6, AND
- column 1 of xbc is less than 6, AND
- column 1 of xcd is less than 6
How to operate > and > to extract a matrix?
2 vues (au cours des 30 derniers jours)
Afficher commentaires plus anciens
MAHMOUD ALZIOUD
le 17 Nov 2017
Commenté : MAHMOUD ALZIOUD
le 19 Nov 2017
Dear all, I have a matrix and i need to extract a smaller matrix based on a condition, this condition took the following shape as Mr Walter once advised me, xab and xbc and xcd are from different columns, but when i run it i found that the new matrix Qua1 took a value that is larger than 6 ! how can i fix this please.
mask1 = xab(:,1)<6 & xbc(:,1)<6 & xcd(:,1)<6;
Qua1=M(mask1, :);
0 commentaires
Réponse acceptée
Image Analyst
le 18 Nov 2017
Modifié(e) : Image Analyst
le 18 Nov 2017
You are getting a mask for this situation
In other words, where all 3 columns of those 3 different arrays are less than 6.
mask1 could be false if any of the x matrices were more than 6 but not all 3, for example 2 were 5 but one of them was 7. Qua1 should not take that row however since mask1 would be false there for that row.
Then you are taking rows where that is the case from M. However, the values of M can be ANYTHING and have no relation to what the values of the x matrices are. The values in M could be up in the millions.
If you want to clip Qua1 to 6, then you can do this:
Qua1(Qua1>=6) = 6;
7 commentaires
Image Analyst
le 19 Nov 2017
They ARE being applied at the same time. Let's make the 3 conditions more explicit so you can see that:
condition1 = 0.1*3.28084*M(:,8) < 6
condition2 = 0.1*3.28084*M(:,10) < 6
condition3 = 0.1*3.28084*M(:,12) < 6;
% Find out which rows meet ALL 3 conditions at the same time.
all3Conditions = condition1 & condition2 & condition3;
% Extracts ALL columns in M but only
% in those rows meeting all 3 conditions.
Qua1 = M(all3Conditions , :);
Plus de réponses (0)
Voir également
Catégories
En savoir plus sur Scatter Plots 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!