Linear Algebra and the C Language/a0il
Negative-definite matrix:
In mathematics, a symmetric matrix M with real entries is positive-definite if the real number xT M x is positive. Negative-definite matrices are defined analogously... Wikipedia: Definite matrix
The eigenvalues of a negative-definite matrix are negative. The matrix is invertible. -A is a positive-definite matrix
Let's check that A = V * EValue * VT.
The inverse matrix of a negative-definite matrix is negative definite.
If A is negative-definite and if s is a strictly positive real number, then s*A is negative definite.
Code study
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