# How can I delete some rows of a matrix

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mr mo on 9 Nov 2017
Commented: mr mo on 9 Nov 2017
Hi. Suppose I have matrix A e.g.
A=[8.2505 4.8825 2.2563 0.0020 0
8.2505 4.8825 2.2687 0.0020 1
8.2505 4.8825 2.2813 0.0020 2
8.2505 4.9325 2.2813 0.0020 0
8.2505 4.9325 2.2938 0.0020 3
8.2755 4.7575 2.2437 0.0020 0
8.2755 4.7575 2.2563 0.0020 0
8.2755 4.7575 2.2687 0.0020 2
8.2755 4.8075 2.2188 0.0020 0
8.2755 4.8075 2.2313 0.0020 3
8.2755 4.8075 2.2437 0.0020 1
8.2755 4.8075 2.2563 0.0010 0
8.2755 4.8075 2.2687 0.0010 2];
I want to delete the rows that their fifth column values are unequal to 0 and at the end I want to have the new matrix A without these rows.
Thanks a lot.

dpb on 9 Nov 2017
Which leaves a column of zeros???
mr mo on 9 Nov 2017
At the end I want this :
A=[8.2505 4.8825 2.2563 0.0020 0
8.2505 4.9325 2.2813 0.0020 0
8.2755 4.7575 2.2437 0.0020 0
8.2755 4.7575 2.2563 0.0020 0
8.2755 4.8075 2.2188 0.0020 0
8.2755 4.8075 2.2563 0.0010 0];

James Tursa on 9 Nov 2017
Edited: James Tursa on 9 Nov 2017
A = A(A(:,5)==0,:);
or
A(A(:,5)~=0,:) = [];

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mr mo on 9 Nov 2017
At the end I want this :
A=[8.2505 4.8825 2.2563 0.0020 0
8.2505 4.9325 2.2813 0.0020 0
8.2755 4.7575 2.2437 0.0020 0
8.2755 4.7575 2.2563 0.0020 0
8.2755 4.8075 2.2188 0.0020 0
8.2755 4.8075 2.2563 0.0010 0];
James Tursa on 9 Nov 2017
This code gives the desired result you posted above. So I am not certain what the problem is at this point.
mr mo on 9 Nov 2017
I made a little mistake. you're right. Thanks a lot.