# how to delete an entire column from a matrix if there is a certain number in that column?

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Joseph 2 Jun 2017
Edited: Guillaume 2 Jun 2017
lets say i have a matrix as below:
A =
1 1 1 1 1
2 2 2 2 2
3 3 3 9 3
i wan to delete the entire column if there is element with the value of 9 in it and get the matrix B as below:
B =
1 1 1 1
2 2 2 2
3 3 3 3
i should mention that in reality may matrix size is much greater than this with the size of A(150,32024), so i need to do it in a for loop, or if anyone has any other idea, i really appreciate it.
thank you

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Guillaume 2 Jun 2017
so i need to do it in a for loop. The size of the matrix is irrelevant to the method you use for solving your problem. In fact, the bigger the matrix, the more likely that using for loops is the wrong solution.
Star's and dpb answers are going to be a lot more efficient than a loop.

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Star Strider 2 Jun 2017
See if this does what you want:
B = A(:,~any(A==9,1))

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dpb 2 Jun 2017
B=A(:,~any(A==9));
If you don't need A any longer, it's just a simple to do it in place...
A(:,any(A==9))=[];

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