many thanks, it worked beautifully, esp using 'unique' for those pesky duplcates values!
How to select 2nd largest number (or largest if no 2nd largest)
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I need to find the second largest number in a vector but the number of elements from 4 to 1 so sometimes there is no second largest number (only the largest number) and in this case I can use the largest number.
I started with b=sort(a) c=(b(:,end-1)
but obviously I get an error when there is only 1 element.
Sorry if I am missing the obvious here!
Accepted Answer
Matt Tearle
on 30 Sep 2011
Is it possible to have repeated values? If so, what do you define as the "second largest" value? Eg secondmax([1 2 3 3]) = 2? or 3?
y = [x(1),unique(x)];
z = y(end-1);
gives the first option. Replacing unique with sort gives the second.
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More Answers (2)
Wayne King
on 30 Sep 2011
Hi Julie, one simple way is
N = 1;
x = randn(N,1);
b = sort(x,'descend');
if (length(b)>1)
b(2)
else
b(1)
end
1 Comment
Jan
on 30 Sep 2011
There are some methods:
b = sort(a);
c = b(max(1, end-1));
Or:
b = sort(a, 'descending');
c = b(max(2, length(b)));
Or:
if length(a) == 1
c = a;
else
b = sort(a, 'descending');
c = b(2);
end
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