Filter value from multiple columns

Question

Augusto Gabriel da Costa Pereira 2023-2-9

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/1909695-filter-value-from-multiple-columns

评论： Mathieu NOE 2023-2-9

采纳的回答： Mathieu NOE

tNino1_2.mat

在 MATLAB Online 中打开

I have the following array named "tNino1_2"

I want to filter the value equal to 1 from columns 20, 21, 22, 23 and 24

The script I'm using is below:

xcol=20:1:24
idx=tNino1_2(tNino1_2(:,xcol)==1,:)
The logical indices in position 1 contain a true value outside of the array bounds.

4 个评论
显示 2更早的评论隐藏 2更早的评论

Dyuman Joshi 2023-2-9

Do you want to find the position (both row and column values) of elements equal to one between columns 20 to 24?

Augusto Gabriel da Costa Pereira 2023-2-9

@Dyuman Joshi exactly

请先登录，再进行评论。

请先登录，再回答此问题。

Answer 1

Mathieu NOE 2023-2-9

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/1909695-filter-value-from-multiple-columns#answer_1167815

在 MATLAB Online 中打开

hello

I assumed you want all the rows where there is at least one 1 in the columns 20 to 24

xcol=20:1:24;
[r,c] = find(tNino1_2(:,xcol)==1);
[ru,ia,ic] = unique(r);
out = tNino1_2(ru,:);

2 个评论
显示无隐藏无

Augusto Gabriel da Costa Pereira 2023-2-9

This script is exactly what I wanted, it worked perfectly.

Thank you Mathieu, you are accurate as always.

Mathieu NOE 2023-2-9

hello Augusto

as always, my pleasure !

请先登录，再进行评论。

Answer 2

Voss 2023-2-9

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/1909695-filter-value-from-multiple-columns#answer_1167795

编辑：Voss 2023-2-9

在 MATLAB Online 中打开

tNino1_2.mat

load tNino1_2

"find the values equal to 1 in columns 20 to 24"

[r,c] = find(tNino1_2(:,20:24) == 1)
r = 28×1
    96
    97
    98
   107
   164
   174
   107
   164
   174
   175
c = 28×1
     1
     1
     1
     1
     1
     1
     2
     2
     2
     2

r is rows and c is columns. Of course, c is relative to columns 20-24 only, so c = 1 means column 20 of the original matrix, c = 2 means column 21, etc.

You can add 19 to c to get the locations of the 1s in the original matrix

Confirm that the elements at those locations are all 1s:

temp = tNino1_2(sub2ind(size(tNino1_2),r,c))
temp = 28×1
     1
     1
     1
     1
     1
     1
     1
     1
     1
     1
all(temp == 1)
ans = logical
   1