How to sort an array in descending order?
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vatankhah
le 8 Sep 2013
Commenté : Image Analyst
le 7 Déc 2017
For example with an array like X that is:
X=[10 3 6 8;
12 5 9 2;
66 4 7 11];
I want a code that gives me the total sort of array X in descending order:
sorted_X=[66 12 11 10;
9 8 7 6;
5 4 3 2];
thanks
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Image Analyst
le 8 Sep 2013
Try this:
[rows, columns] = size(X)
sorted_X = reshape(sort(X(:), 'descend'), [columns, rows])'
It gives you the exact result you showed. It sorts all the elements, regardless of what row or column they started in, then reshapes from a vector back into the shape of the original X matrix.
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Walter Roberson
le 8 Sep 2013
Do the total sort in ascending order, and then reverse the order of the elements.
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venkatesh dixit
le 7 Déc 2017
Modifié(e) : Image Analyst
le 7 Déc 2017
I have a matrix, and I have to keep the columns in ascending order of the sum of the matrix, or descending order or sum of matrix. Kindly tell how to do it. My matrix is as follows:
A=[1 3 3;
4 5 6;
9 18 17]
I have to sort it accordingly so that it becomes
[3 3 1;
6 5 4;
17 18 9];
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Image Analyst
le 7 Déc 2017
Not clear at all. Are you sorting the first row somehow and applying the sort order to the other rows? If so, it's ambiguous because you have 3 in two locations. Like this:
[~, sortOrder] = sort(A(1,:), 'descend')
out = A(:, sortOrder)
Or are you summing horizontally to get the sum along each row, or vertically to get the sum along each column? It's just not clear at all. Please try to explain it more accurately.
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