How can I find the determinant and transpose of a 13*13 matrix without writing all the numbers one by one?

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Efe 2023-11-26

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https://ww2.mathworks.cn/matlabcentral/answers/2052177-how-can-i-find-the-determinant-and-transpose-of-a-13-13-matrix-without-writing-all-the-numbers-one-b

回答： John D'Errico 2023-11-26

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Answer 1

madhan ravi 2023-11-26

在 MATLAB Online 中打开

 doc det
 doc transpose

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Efe 2023-11-26

I'm sorry, I asked the question incompletely. How can I write the matrix in a short way?

Walter Roberson 2023-11-26

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You could construct the matrix using sparse by listing the row numbers and column numbers and corresponding values. I count about 42 non-zero elements, so it would look like

sparse(list_of_42_rows, list_of_42_columns, list_of_42_values)

That would be 42*3 = 126 elements to enter instead of 13*13 = 169 -- but it would also be much easier to get wrong. TANSTAAFL

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Answer 2

Torsten 2023-11-26

移动：Torsten 2023-11-26

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If a matrix is structured as irregularily as the one you posted, there is no other way as to reference its nonzero elements one by one:

A = zeros(13);
A(1,1) = 29/20;
A(1,2) = -1;
A(1,5) = -1/5;
...

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Answer 3

John D'Errico 2023-11-26

You have many almost random looking numbers. So without knowing how they were generate, it is impossible to do better than stuffing the elements of your matrix using either the scheme @Torsten or @Walter Roberson has proposed.

HOWEVER, IF there is some formula that generates those numbers, then you need to write it in MATLAB code. And only you can write that code, since only you know how those coefficients were generated, and what the placement means. But surely there is SOME formula. We cannot guess it however.