What does C(:,:,i)=[Q11 Q12 Q14;Q12 Q22 Q24;Q14 Q24 Q44]; signify?

1 次查看（过去 30 天）
S Priya
S Priya 2021-9-1
评论： Walter Roberson 2021-9-1
What does C(:,:,i)=[Q11 Q12 Q14;Q12 Q22 Q24;Q14 Q24 Q44]; signify?

请先登录，再回答此问题。

回答（1 个）

KSSV
KSSV 2021-9-1
C(:,:,i)=[Q11 Q12 Q14;Q12 Q22 Q24;Q14 Q24 Q44];
In the above C, is 3D matrix initialized as 3*3*p matrix. Each matrix of C, should have a 3x3 matrix. The line says there is a loop (i is the index shown here), for the i'th idex in C, a 3x3 matrix is filled in C. The matrix in RHS is a 3X3 matrix and it's each value is denoted by Q11....Q44, where these values should be either calculated or initilaized.
  2 个评论
S Priya
S Priya 2021-9-1
编辑：S Priya 2021-9-1
Thank you sir.It basically means that...
for i=1:3
C(:,:,1) = [Q11 Q12 Q14;Q12 Q22 Q24;Q14 Q24 Q44]
So, what is the output of
C(:,:,2)=? and C(:,:,3)=?
Walter Roberson
Walter Roberson 2021-9-1
If you only assign to C(:,:,1) inside the for loop, then after the for loop:
  • if C did not exist before the for loop, then C(:,:,2) does not exist
  • if C did exist before the for loop, but its size in the third dimension and all following dimensions was 1 before, then C(:,:,2) does not exist
  • if C did exist before the for loop, and at least one dimension from the third onward was 2 or more, then effectively C gets resized like reshape(C,size(C,1), size(C,2), []) and then (:,:,2) of the result would be extracted

请先登录，再进行评论。

类别

在 Help Center 和 File Exchange 中查找有关 Resizing and Reshaping Matrices 的更多信息

标签

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by