Using a binary matrix as an index to select values from another matrix
显示 更早的评论
Hi all,
I think this is a really beginner question, but I can't seem to find the relevant answers online.
If I have the following matrix:
% 3x2
index_matrix = [0,0;1,0;1,1;]
% 3x2
p = [13,12;11,19;22,23;]
I wish to select the corresponding value in p if the value at the same position in index_matrix = 1.
If the value in index_matrix is 0, then the corresponding value should be set to 0.
That is, I wish to have the following:
result = [0,0;11,0;22,23;]
Thank you in advance!
采纳的回答
Kai Franke
2019-6-14
result = p.*index_matrix
matrix multiplication is the keyword hehe
Best regards.
3 个评论
"matrix multiplication is the keyword hehe"
Matrix multiplcation is something quite different, as the MATLAB documentation explains:
Kai Franke
2019-6-14
@Stephen Cobeldick
oh yeah you are absolutely right! Element-wise multiplication. My answer was very sloppy, my bad. Thanks for the correction!
更多回答（1 个）
Stephen23
2019-6-14
>> X = [1,0;3.5,1;0,6];
>> p = [13,12;11,19;22,23];
>> p.*(X==1)
ans =
13 0
0 19
0 0
类别
在 帮助中心 和 File Exchange 中查找有关 Logical 的更多信息
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!
Translated by 
