Noelia B. Rios

activity

20162025

collaborators

Showing math.FAShow all

5 papers · 1 filter

math.FA2022

Best multi-valued approximants via multi-designs

María José Benac, Noelia Belén Rios, Mariano Ruiz

Let $d = (d_{j})_{j \in I_{m}} \in N^{m}$ be a decreasing finite sequence of positive integers, and let $α = (α_{i})_{i \in I_{n}}$ be a finite and non-increasin…

math.FA2020

Local extrema for Procustes problems in the set of positive definite matrices

Pablo Calderón, Noelia B. Rios, Mariano A. Ruiz

Given two positive definite matrices $A$ and $B$ , a well known result by Gelfand, Naimark and Lidskii establishes a relationship between the eigenvalues of $A$ and $B$ and those of…

math.FA2018

Generalized frame operator distance problems

Pedro Massey, Noelia Rios, Demetrio Stojanoff

Let $S \in M_{d} (C)^{+}$ be a positive semidefinite $d \times d$ complex matrix and let $a = (a_{i})_{i \in I_{k}} \in R_{> 0}^{k}$ , indexed by $\mathbb{I…

math.FA2018

Local Lidskii's theorems for unitarily invariant norms

Pedro Massey, Noelia B. Rios, Demetrio Stojanoff

Lidskii's additive inequalities (both for eigenvalues and singular values) can be interpreted as an explicit description of global minimizers of functions that are built on unitari…

math.FA2016

Frame completions with prescribed norms: local minimizers and applications

Pedro G. Massey, Noelia B. Rios, Demetrio Stojanoff

Let $F_{0} = {f_{i}}_{i \in I_{n_{0}}}$ be a finite sequence of vectors in $C^{d}$ and let $a = (a_{i})_{i \in I_{k}}$ be a finite sequence of positive nu…