24 citations · 24 across the 13 of their papers we have counts for
15 papers
A Weak Topology on Metric Spaces
Armando W. Gutiérrez, Olavi Nevanlinna
We use metric functionals to build a weak topology associated with -weak convergence on metric spaces. We also show the existence of a sequence in the space that is unb…
Multicentric representation of piecewise constant holomorphic functions and Hermite interpolation
Olavi Nevanlinna, Tiina Vesanen
In multicentric representation of piecewise holomorphic functions one combines Lagrange interpolation at roots of a polynomial with convergent power series of as the "coeff…
Metric functionals and weak convergence
Armando W. Gutiérrez, Olavi Nevanlinna
We introduce a notion of weak convergence in arbitrary metric spaces. Metric functionals are key in our analysis: weak convergence of sequences in a given metric space is tested ag…
Subinvariant metric functionals for nonexpansive mappings
Armando W. Gutiérrez, Olavi Nevanlinna
We investigate the existence of subinvariant metric functionals for commuting families of nonexpansive mappings in noncompact subsets of Banach spaces. Our findings underscore the…
Gradients of Quotients and Eigenvalue Problems
Marko Huhtanen, Olavi Nevanlinna
Intertwining analysis, algebra, numerical analysis and optimization, computing conjugate co-gradients of real-valued quotients gives rise to eigenvalue problems. In the linear Herm…
Simplifying operators by polynomials
Olavi Nevanlinna
We collect and organise known results and add some new ones of the following nature: if A is a bounded operator in a Hilbert or Banach space, does there exist a nonconstant polynom…