Zeroing matrix elements outside of a certain range.
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edit: I changed my data example input because it was a bad example that accepted some solution that are not going to work in general
Hi guys, I would like to zero the outer elements of a matrix so that they are not counted in a sum / average.
Basically the matrix is experimental data and each column comes from a different experiment and the first and last datapoints in each experiment are likely to be artefact.
for example:
data = rand(5,2)
and I would like to keep the points 1:4 in the first column (experiment 1) and 2:5 in the second column (experiment 2).
Ideally, I would like to input a matrix of bounds of valid range:
range = [1,4;2,5]
and I would like the data for the index not in that range to be zeroed and ideally without a loop
like
data(index<range(1,:) or index>range(2,:)) = 0
but of course this is not the right line...
A long way would be:
remove = ones(5,2)
remove(range(1,1):range(1,2),1) = 0
remove(range(2,1):range(2,2),2) = 0
data(remove)=0
ah no, even that doesn't work. But even if it would, that's way too inefficient. Sorry, really struggling...
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Réponses (2)
Dyuman Joshi
le 15 Fév 2024
A simple approach via indexing -
data = [1;2;3;4;5].*ones(5,2).*[0.5,0.4]
out = [data(1:4,1) data(2:5,2)]
Catalytic
le 18 Fév 2024
Zeroing the data will not exclude it from the average. You should use NaNs,
data = [1;2;3;4;5].*ones(5,2).*[0.5,0.4]
range = [1,0;
inf,1.7]
data(range(1,:)>data | data>range(2,:))=nan
Average=mean(data,1,'omitnan')
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