Results 21 to 30 of about 1,624,240 (288)

Chromatic number and signless Laplacian spectral radius of graphs [PDF]

Transactions on Combinatorics, 2022
For any simple graph $G$, the signless Laplacian matrix of $G$ is defined as $D(G)+A(G)$, where $D(G)$ and $A(G)$ are the diagonal matrix of vertex degrees and the adjacency matrix of $G$, respectively.
Mohammad Reza Oboudi
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On graphs with distance Laplacian eigenvalues of multiplicity n−4

AKCE International Journal of Graphs and Combinatorics, 2023
Let G be a connected simple graph with n vertices. The distance Laplacian matrix [Formula: see text] is defined as [Formula: see text], where [Formula: see text] is the diagonal matrix of vertex transmissions and [Formula: see text] is the distance ...
Saleem Khan, S. Pirzada, A. Somasundaram
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Monophonic Distance Laplacian Energy of Transformation Graphs Sn^++-,Sn^{+-+},Sn^{+++}

Ratio Mathematica, 2023
Let $G$ be a simple connected graph of order $n$, $v_{i}$ its vertex. Let $\delta^{L}_{1}, \delta^{L}_{2}, \ldots, \delta^{L}_{n}$ be the eigenvalues of the distance Laplacian matrix $D^{L}$ of $G$. The distance Laplacian energy is denoted by $LE_{D}(G)$.
Diana R, Binu Selin T
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The normalized distance Laplacian

Special Matrices, 2021
The distance matrix 𝒟(G) of a connected graph G is the matrix containing the pairwise distances between vertices. The transmission of a vertex vi in G is the sum of the distances from vi to all other vertices and T(G) is the diagonal matrix of ...
Reinhart Carolyn
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Sparse Graph Learning Under Laplacian-Related Constraints

IEEE Access, 2021
We consider the problem of learning a sparse undirected graph underlying a given set of multivariate data. We focus on graph Laplacian-related constraints on the sparse precision matrix that encodes conditional dependence between the random variables ...
Jitendra K. Tugnait
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An analog of Matrix Tree Theorem for signless Laplacians [PDF]

Linear Algebra and its Applications, 2019
A spanning tree of a graph is a connected subgraph on all vertices with the minimum number of edges. The number of spanning trees in a graph $G$ is given by Matrix Tree Theorem in terms of principal minors of Laplacian matrix of $G$. We show a similar combinatorial interpretation for principal minors of signless Laplacian $Q$.
Keivan Hassani Monfared, Sudipta Mallik
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Approximations of the Generalized Inverse of the Graph Laplacian Matrix [PDF]

Internet Mathematics, 2012
We devise methods for finding approximations of the generalized inverse of the graph Laplacian matrix, which arises in many graph-theoretic applications. Finding this matrix in its entirety involves solving a matrix inversion problem, which is resource-demanding in terms of consumed time and memory and hence impractical whenever the graph is relatively
BOZZO, Enrico, FRANCESCHET, Massimo
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Spectral properties for the Laplacian of a generalized Wigner matrix [PDF]

Random Matrices: Theory and Applications, 2021
In this paper, we consider the spectrum of a Laplacian matrix, also known as Markov matrices where the entries of the matrix are independent but have a variance profile. Motivated by recent works on generalized Wigner matrices we assume that the variance profile gives rise to a sequence of graphons.
Chatterjee, A., Hazra, R.S.
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More on Spectral Analysis of Signed Networks

Complexity, 2018
Spectral graph theory plays a key role in analyzing the structure of social (signed) networks. In this paper we continue to study some properties of (normalized) Laplacian matrix of signed networks. Sufficient and necessary conditions for the singularity
Guihai Yu, Hui Qu
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Trees with matrix weights: Laplacian matrix and characteristic-like vertices

Linear Algebra and its Applications, 2022
It is known that there is an alternative characterization of characteristic vertices for trees with positive weights on their edges via Perron values and Perron branches. Moreover, the algebraic connectivity of a tree with positive edge weights can be expressed in terms of Perron value.
Swetha Ganesh, Sumit Mohanty
openaire   +2 more sources