How to change an entire column.

Question

Anton Mulder 2013-4-29

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https://ww2.mathworks.cn/matlabcentral/answers/73956-how-to-change-an-entire-column

Hi,

I have a matrix with a dimension of 10x640. The matrix is filled with ones and zeros. If there is a zero in one of columns, I want the entire column to be zeros. How can I do this?

Example:

[[1,0,1];[1,1,1]]

Output should be:

[[1,0,1];[1,0,1]]

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Answer 1

Iman Ansari 2013-4-29

1
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https://ww2.mathworks.cn/matlabcentral/answers/73956-how-to-change-an-entire-column#answer_83823

在 MATLAB Online 中打开

 A = randi(10,[10 640])-1;
 B = A;
 B(:,sum(A==0)>0)=0;

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Jan 2013-4-29

any(A, 2) is faster than sum(A==0)>0.

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Answer 2

Image Analyst 2013-4-29

3
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/73956-how-to-change-an-entire-column#answer_83824

在 MATLAB Online 中打开

Try this:

% Make sample data.
A = ones(10, 640);
% Stick a zero in columns 3, and 5.
A(9, 3) = 0;
A(8, 5) = 0
% Now that we have some sample data, do what Anton wants.
% Find out which columns have zeros in them
columnsWithZeros = any(~A);  % Assumes A is only 0's and 1's.
A(:, columnsWithZeros) = 0; % Set whole column(s) to zero.