How to Erase a Row in a Matrix, if It has Complex Numbers?

Question

ercan duzgun 2021-2-7

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/738472-how-to-erase-a-row-in-a-matrix-if-it-has-complex-numbers

编辑： ercan duzgun 2021-2-7

I have a table in matrix form (n row,10 column). The n row might changed according to previous codes, it is not constant.

I would like to check whether there is any complex number in the table, then if there is a complex number in any row, I would like to erase all that row. (There would be less rows than n rows).

How can I do this? My code is below:

Table= [1 2 3 4 5 6 7 8 9 10; 1+i  2 3 4 5 6 7 8 9 10; 10 9 8 7 6 5 4 3 2 1]; % Table row size is not fixed, not always 3. 
% Therefore I find its size here below
[size1,size2]=Table
k=0;
for i=1:1:size1;
  if imag(Table(i,1))~=0 | imag(Table(i,2))~=0 | imag(Table(i,3))~=0 | ...
     imag(Table(i,4))~=0 | imag(Table(i,5))~=0 | imag(Table(i,6))~=0 | ...
     imag(Table(i,7))~=0 | imag(Table(i,8))~=0 | imag(Table(i,9))~=0 | ...
     imag(Table(i,10))~=0;
    k=k+1;
    rows_would_be_deleted(k,1)=i;
end
end
Table_old=Table;
Table(rows_would_be_deleted(:,1),:)=[];
Table_new=Table;

This code works, if there is any complex number in the table. However, it should keep the table, if there was no complex number. But, if there is no complex number, the if block in my code isn't executed. And it gives error with unknown variable/function "rows_would_be_deleted".

How can I fix this? Any simpler code is also welcomed. Thanks in advance.

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。

请先登录，再回答此问题。

Answer 1

Walter Roberson 2021-2-7

1
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/738472-how-to-erase-a-row-in-a-matrix-if-it-has-complex-numbers#answer_616957

在 MATLAB Online 中打开

Table= [1 2 3 4 5 6 7 8 9 10; 1+i  2 3 4 5 6 7 8 9 10; 10 9 8 7 6 5 4 3 2 1]; 
mask = any(imag(Table),2);
Table(mask,:) = [];
Table
Table = 2×10
     1     2     3     4     5     6     7     8     9    10
    10     9     8     7     6     5     4     3     2     1