Row manipulation in the heterogeneous tabular forms with a hexadecimal grid graph model

A nonnegative symmetric matrix $B$ has row maxima prescribed by a given vector $r$, if for each index $i$, the maximum entry in the $i$th row of $B$ equals $r_i$. This paper presents necessary and sufficient conditions so that for a given nonnegative ...

Matrix $M$ is $k$-concise if the finite entries of each column of $M$ consist of $k$ or fewer intervals of identical numbers. We give an $O(n+m)$-time algorithm to compute the row minima of any $O(1)$-concise $n\times m$ matrix. Our algorithm yields the ...

Given a sparse, symmetric positive definite matrix C and an associated sparse Cholesky factorization LDL$\tr$, we develop sparse techniques for updating the factorization after a symmetric modification of a row and column of C. We show how the ...