Questions tagged [m-matrix]
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9 questions
1 vote
0 answers
93 views
Characterization of the inverse of a diagonally dominant symmetric M-matrix
I was looking for a proof or counter-example for a hypothesis that states that the inverse of a nonsingular nonnegative symmetric diagonally dominant matrix with the same value on the diagonal is a ...
4 votes
2 answers
241 views
Requesting reference for result from linear algebra on Schur complements of M-matrices
In my research in linear algebra, I have come across a useful result stating that the Schur complement of a principal non-singular submatrix of an M-matrix is also an M-matrix, but I have never found ...
1 vote
1 answer
204 views
Find a matrix and its inverse satisfying lower and upper bounds
I reduced a problem of matrix completion to the problem find $A,B$ such that $AB=I$ $A_{min}\leq A \leq A_{max}$ $B_{min}\leq B \leq B_{max}$ One possible approach would be to just minimize $\|AB-...
11 votes
2 answers
788 views
Product $PVPVP$ is elementwise nonnegative?
Let $P\in \mathbb{R}^{n\times n}$ be the inverse of a positive definite M-matrix and $V\in \mathbb{R}^{n\times n}$ be any diagonal matrix. Prove (or disprove) that $PVPVP$ is elementwise nonnegative. ...
8 votes
3 answers
808 views
Is there an efficient algorithm to check whether a matrix is symmetrizable using only permutation matrix?
Is there any known efficient algorithm (something that works better than brute-force algorithm) to check that given a $(0,1)$-$d \times d$ matrix $A$, is there a permutation matrix $P$ of the same ...
1 vote
0 answers
283 views
M-matrix with nonconstant entries properties
I have a matrix $J(x)$ with $J_{ij}(x)=f_{ij}(x)$ where vector $x$ is $x=x_1, x_2, ..., x_m$. I have shown that $J(x)$ is an M-matrix for all $x$. There is known review paper by Plemmons (1977) of 40 ...
3 votes
0 answers
177 views
inverse M-matrix times mixed-sign vector
Recently a colleague and I came across this unusual phenomenon. Take $M\in\mathbb{R}^{n\times n}$ a singular irreducible M-matrix, and $b\in\mathbb{R}^{n}$ such that the system $Mx=b$ is solvable (so,...
2 votes
1 answer
728 views
When is a Schur complement an $M$-matrix?
Let $F=\begin{bmatrix}A & B \\\\ B^{T} & D\end{bmatrix}$ be symmetric and strictly diagonally dominant (thus an $H$-matrix). I also know that $B>0$ entrywise. What I am trying to show is ...
2 votes
1 answer
2k views
Irreducible non-singular M-matrices and complex numbers
It is well known that a non-singular M-matrix that is irreducible has a strictly positive inverse (all entries $>0$). An M-matrix is a matrix that has eigenvalues with positive real part, and the ...