how to delete rows from matrix

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m. muner
m. muner 2016-5-24
评论： Anoire BEN JDIDIA 2016-10-17
hello i have 53*3 matrix but include rows that three column of the row are zeros i want to delete the entire row i tried this but since every delete shift the location of the other rows i had problem with the for loop so what can i do to overcome this
[c u]=size(test_ary); %dimensions
for i=1:c
for b=1:u
if(test_ary(i,1)==(o)));
test_ary(i,:)=[];
end
end
end

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采纳的回答

James Tursa
James Tursa 2016-5-24
编辑：James Tursa 2016-5-24
Replace your for-loop with this vectorized code:
x = all(test_ary==0,2); % Which rows are all 0's
test_ary(x,:) = []; % Delete those rows

更多回答（3 个）

Jos (10584)
Jos (10584) 2016-5-26
Using the statement "test_ary(i,:) = []" you will change the size of it, which will cause problems!
tf = all(test_ary==0,2) % true for rows with only 0's
test_ary(tf,:) = [] % remove those rows using logical indexing
Azzi Abdelmalek
Azzi Abdelmalek 2016-5-24
out=test_ary(~ismember(test_ary,[0 0 0],'rows'),:)
  2 个评论
m. muner
m. muner 2016-5-26
just create new matrix called out which is same as the original test_ary

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Anoire BEN JDIDIA
Anoire BEN JDIDIA 2016-10-14
I have a big matrix 599794x2 i want to delete rows which contains values which repeats for exemple if A=[1,1;2,1;3,1;4,1;5,2;6,2;7,2]; i want to have A=[1,1;5,2]
  2 个评论
James Tursa
James Tursa 2016-10-14
In the future open up a new Question for this rather than piggyback on an existing Question. But I will answer this here this time:
A = A(logical([1;diff(A(:,2))]),:);

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