
The relation between trace and determinant of a matrix
Jan 4, 2017 · Let $M$ be a symmetric $n \\times n$ matrix. Is there any equality or inequality that relates the trace and determinant of $M$?
Obtaining full $V$ matrix from Eigen's SVD function
Dec 23, 2025 · What is the size of the matrix whose SVD you want? If you know it a priori, what is the rank of your matrix whose SVD you want?
Singular vs. Non-singular - Mathematics Stack Exchange
Feb 17, 2020 · A matrix/system of equations is singular is there are infinite solutions, but iff there is a unique solution then its non-singular? I haven't learned how to take a determinant yet. However, my …
Compute the characteristic equation of a $3 \times 3$ matrix
May 1, 2025 · Coming up with the last eigenvalue should be easy if we use the fact that the trace of the matrix is the sum of the eigenvalues. The eigenvalues for this matrix are thus $\lambda_1 = 1, …
What is the difference between the Jacobian, Hessian and the Gradient ...
May 13, 2020 · The Hessian Simply, the Hessian is the matrix of second order mixed partials of a scalar field. $$\mathbf {H}_ {i, j}=\frac {\partial^ {2} f} {\partial x_ {i} \partial x_ {j}}$$ In summation: Gradient: …
Regarding computing singular values, using the covariance matrix as ...
Dec 18, 2025 · Say X ∈ Rn × d X ∈, with n ≫ d. If the (very) tall matrix X is centered, then the singular values of X are σi(X) = √λi(X), where the λi(X) are the eigenvalues of the covariance matrix X⊤X. …
How to normalize the matrix? - Mathematics Stack Exchange
Nov 17, 2017 · In fact, a quick check on Wolfram|Alpha shows that for a 2x2 matrix to be normalizable, the top left index must exactly equal the negative of the bottom right index (among other conditions) …
Inverse of a $2 \times 2$ block matrix - Mathematics Stack Exchange
Oct 1, 2016 · One good reference is the Handbook Matrix Mathematics Theory, Facts and Formulas by Dennis S. Bernstein. Let $\mathbb {F}$ equal to $\mathbb {R}$ or $\mathbb {C}$.
Getting the inverse of a lower/upper triangular matrix
For a lower triangular matrix, the inverse of itself should be easy to find because that's the idea of the LU decomposition, am I right? For many of the lower or upper triangular matrices, often I ...
How to find the determinant of this $6\times 6$ X-matrix?
Aug 9, 2020 · I have no clue on how this kind of matrices can be solved. Can anyone give a general strategy on how to solve matrices whose size are greater that $3\times 3$? That would be really helpful.