Count the number of non-zero elements of a column/row of a 2D-Matrix?

Question

Ines 2012-5-3

2
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/37323-count-the-number-of-non-zero-elements-of-a-column-row-of-a-2d-matrix

编辑： Souarv De 2023-5-23

Hello everyone,

I have a 2D Matrix and I want to make Matlab count the number of non-zero Elements within one row, is there a straightforward way to do this? Many thanks

1 个评论
显示 -1更早的评论隐藏 -1更早的评论

Eldar Cohen 2021-8-31

sum(A'~=0)

请先登录，再进行评论。

请先登录，再回答此问题。

Answer 1

James Tursa 2012-5-3

6
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/37323-count-the-number-of-non-zero-elements-of-a-column-row-of-a-2d-matrix#answer_46605

在 MATLAB Online 中打开

sum(X(row_number,:)~=0)

1 个评论
显示 -1更早的评论隐藏 -1更早的评论

Daniel Roßfeld 2021-8-17

在 MATLAB Online 中打开

Alternatively, use

nnz(A(row, :))

请先登录，再进行评论。

Answer 2

Thomas 2012-5-3

12
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/37323-count-the-number-of-non-zero-elements-of-a-column-row-of-a-2d-matrix#answer_46604

在 MATLAB Online 中打开

Try:

 a=[3 0 0;0 2 0; 1 0 4]   %input matrix
 sum(a~=0,2)              % no. of nozero elements in each row

0 个评论
显示 -2更早的评论隐藏 -2更早的评论

请先登录，再进行评论。

Answer 3

Muhammad Ilias Amin 2014-5-12

4
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/37323-count-the-number-of-non-zero-elements-of-a-column-row-of-a-2d-matrix#answer_136464

a = [3 0 0; 0 2 0; 1 0 0];

To get the no of non zero columns: sum( all( a == 0, 1 ) );

To get the no of non zero rows: sum( all( a == 0, 2 ) );

1 个评论
显示 -1更早的评论隐藏 -1更早的评论

Souarv De 2023-5-23

编辑：Souarv De 2023-5-23

A small correction in the text part to the above two lines code is that it will give no of zero columns and rows, not non-zero columns and non-zero rows.

请先登录，再进行评论。