detect same value
显示 更早的评论
how do I detect on the elements of a (:, 1) there is the same value?
a=[1 34;
2 33;
2 45;
3 32;
4 65;
4 99;
5 11;
1 33;
6 22]
采纳的回答
Walter Roberson
2011-6-10
u = unique(a(:,1));
if length(u) ~= size(a,1)
%there were duplicates
end
If you want to find out which are equal to which,
bsxfun(@eq, a(:,1), a(:,1).'))
and that will return a logical matrix in which for row r, column c is set if a(r) == a(c)
2 个评论
M M
2013-3-6
How would you isolate the duplicated values? So I would know which values are duplicated and use them for another purpose? (The opposite of the unique function)
Walter Roberson
2013-3-6
setdiff(V, unique(V)) %for vector V, results are in sorted order
or
T = bsxfun(@eq, V(:), V(:).'); %for vector V
sum(T) > 1 %will be true at index K if V(K) is not unique
更多回答（0 个）
类别
在 帮助中心 和 File Exchange 中查找有关 Performance and Memory 的更多信息
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!
Translated by 
