Printing positive numbers backwards
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Hi all,
I was just wondering if anyone could help me out with some code to go through a matrix of numbers and find the positive numbers and print only them (remove the negative numbers) in a new array but also print them in reverse order,
Thanks a lot!
1 个评论
Please show us what you have tried so far.
You would have made significant progress on this by doing the introductory tutorials:
回答（1 个）
Rajani Mishra
2019-7-16
Hi,
I understand that you want to extract positive numbers from matrix and store them in a new array and then traverse the new array in reverse order.
Refer this code:
[row,col] = size(mt)
arr = [];
for i = 1:row
for j = 1:col
if mt(i,j) > 0
arr(numel(arr) + 1) = mt(i,j);
end
end
end
for i = numel(arr):-1:1
disp(arr(i));
end
1 个评论
Is there are reason why this answer does not use MATLAB's basic (and most useful) features, e.g. logical indexing, code vectorization, etc.?
Note that the output array should be preallocated:
It is much simpler to just use efficient logical indexing (this gives the same output):
B = mt.';
flipud(B(B>0))
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2019-7-2
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