obtain data using columns data indices

1 次查看（过去 30 天）

显示更早的评论

Farman Shah 2018-12-13

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/435496-obtain-data-using-columns-data-indices

评论： Farman Shah 2018-12-13

采纳的回答： Walter Roberson

i have data A=( 3,5,3,1,4 ) in a column and

B=[ 4 6 9 1 3

2 7 2 5 7

7 3 1 8 2

4 1 6 9 1

2 5 8 3 6]

and i want: as in A first element is 3 and for this i want to get first element of column 3 row 1 from B which is 9. The second element of A is 5 and for this i want to get the the 2nd element of column 5 and row 2 from B which is 7 ,and do the process for all other elements . how to do this? the requried elememts are bold and underlined

any help will be really appriciated.........thanks in advance

2 个评论
显示无隐藏无

madhan ravi 2018-12-13

Dude just give the example of your desired output

Farman Shah 2018-12-13

编辑：Farman Shah 2018-12-13

[9,7,1,4,3] is the disired output. which is underlined also

请先登录，再进行评论。

请先登录，再回答此问题。

采纳的回答

Walter Roberson 2018-12-13

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/435496-obtain-data-using-columns-data-indices#answer_352106

在 MATLAB Online 中打开

B(sub2ind( size(B), 1:length(A), A))

3 个评论
显示 1更早的评论隐藏 1更早的评论

Walter Roberson 2018-12-13

在 MATLAB Online 中打开

B(sub2ind( size(B), (1:length(A)).', A(:)))

The above will work regardless of whether A is a row or column vector. However, it will return a column of results either way. If you need a row of results, put .' at the end:

B(sub2ind( size(B), (1:length(A)).', A(:))).'

Farman Shah 2018-12-13