I want to get vector of det

Question

Jonghun 2013-7-28

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此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/83368-i-want-to-get-vector-of-det

-my code-

a=[1 0 0 0]; b=[0 1 0 0]; c=[0 0 1 0]; d=[0 0 0 1];

detvector=det([a b c d]);

-I want to get detvector=[det([a(1) b(1) c(1) d(1)]),det([a(2) b(2) c(2) d(2)]),det([a(3) b(3) c(3) d(3)]),det([a(4) b(4) c(4) d(4)])]. But my code doesn't works. How can I solve it?

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Jan 2013-7-28

编辑：Jan 2013-7-28

Please follow the "? Help" link to learn how to format code in the forum. Thanks.

Instead of posting "my code does not work", an explicit description would be more useful: Post the code and a copy of the error message, or explain the difference between your expectations and the results.

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Answer 1

Roger Stafford 2013-7-28

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在 MATLAB Online 中打开

If you express the matrix properly as a 4 x 4 matrix,

det([a;b;c;d]),

matlab will give you its determinant. Your expression

[a b c d]

is that of a 1 x 16 row vector and it is meaningless to speak of its "determinant".

However, you don't need matlab to find the determinant you apparently have in mind. Of the twenty-four products that comprise this determinant, only one is non-zero and that will be the product of the four 1's, giving you a resultant determinant value of 1.