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Creating a submatrix from a matrix

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Konstantinos
Konstantinos 2014-12-4
评论： Ioannis Aggelos 2024-4-29
I want a code to create a matrix which consist of rows and columns of another matrix.
i.e. A (4X4) = [ 1 2 3 4; 5 6 7 8; 1 3 5 7; 2 4 6 8; ]
The submatrix B consist of the { 1, 2, 4 }rows of A and the { 2,3 }columns of A:
Β (3Χ2) = [ 2 3; 6 7; 4 6; ]
Any help could be useful.
Thanks in advance!
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said mohamed
said mohamed 2021-5-5
Using the matrix A = [5 1 11; 7 13 3; 8 5 2], the matrix B is constructed as B = [A A A; A A A; A A A]. Which of the following is the result of the operation K = L * J, made using the submatrices of matrix B, L = B (1: 3,3: 5) and J = B (2: 4,2: 3)?

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Azzi Abdelmalek
Azzi Abdelmalek 2014-12-4
编辑：Azzi Abdelmalek 2014-12-4
A= [ 1 2 3 4; 5 6 7 8; 1 3 5 7; 2 4 6 8; ]
B=A([1 2 4],[2 3])
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said mohamed
said mohamed 2021-5-5
Using the matrix A = [5 1 11; 7 13 3; 8 5 2], the matrix B is constructed as B = [A A A; A A A; A A A]. Which of the following is the result of the operation K = L * J, made using the submatrices of matrix B, L = B (1: 3,3: 5) and J = B (2: 4,2: 3)?

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VANSHUL CHOUDHARY
VANSHUL CHOUDHARY 2021-8-20
A = rand(4,3);
% Get those elements of A that are located in rows 3 to 4 and
% column 2 to 3.
sub_matrix = A(3:4,2:3);
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Dyuman Joshi
Dyuman Joshi 2023-11-12
@Justin Paulan, experiment with the methods shown in the Answers in this thread.

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