Algebraic geometric methods in studying splines

Sipahi Ös, Neslihan
In this thesis, our main objects of interest are piecewise polynomial functions (splines). For a polyhedral complex $\Delta$ in $\mathbb{\R}^n$, $C^{r}(\Delta)$ denotes the set of piecewise polynomial functions defined on $\Delta$. Determining the dimension of the space of splines with polynomials having degree at most $k$, denoted by $C^r_k(\Delta)$, is an important problem, which has many applications. In this thesis, we first give an exposition on splines and introduce different algebraic geometric methods used to compute the dimension of splines both on polyhedral and simplicial complexes. Then we generalize the important result of Mcdonald and Schenck \cite{McdSch} on planar splines on a polyhedral complex. Also, by using the method in \cite{GeraSch}, we make generalizations on the dimension of the spaces of splines on simplicial complexes in dimension three. This generalizaton includes simplicial complexes having no interior points, and octahedrons with one interior point. In the latter case, we make some generalizations by considering the number of linearly independent interior planes.


Calculations of the roots of classical orthogonal polynomials: an application to gaussian quadrature
Shaidolda, Gulnaz; Taşeli, Hasan; Department of Mathematics (2019)
This thesis focuses on classical orthogonal polynomials namely Jacobi, Laguerre and Hermite polynomials and a method to calculate the roots of these polynomials is constructed. The roots are expressed as the eigenvalues of a tridiagonal matrix whose coefficients depend on the recurrence formula for the classical orthogonal polynomials. These approximations of roots are used as method of computation of Gaussian quadratures. Then the discussion of the numerical results are then introduced to deduce the effici...
A New Combinatorial Identity for Catalan Numbers
Aker, Kursat; Gursoy, Aysin Erkan (2017-10-01)
In this article, we prove a conjecture about the equality of two generating functions described in "From Parking Functions to Gelfand Pairs (Aker, Can 2012)" attached to two sets whose cardinalities are given by Catalan numbers: We establish a combinatorial bijection between the two sets on which the two generating functions were based on.
Algebraic Nahm transform for parabolic Higgs bundles on P-1
Aker, Kursat; Szabo, Szilard (2014-01-01)
We formulate the Nahm transform in the context of parabolic Higgs bundles on P-1 and extend its scope in completely algebraic terms. This transform requires parabolic Higgs bundles to satisfy an admissibility condition and allows Higgs fields to have poles of arbitrary order and arbitrary behavior. Our methods are constructive in nature and examples are provided. The extended Nahm transform is established as an algebraic duality between moduli spaces of parabolic Higgs bundles. The guiding principle behind ...
Symbolic polynomial interpolation using Mathematica
Yazıcı, Adnan; Ergenc, T (2004-01-01)
This paper discusses teaching polynomial interpolation with the help of Mathematica. The symbolic power of Mathematica is utilized to prove a theorem for the error term in Lagrange interpolating formula. Derivation of the Lagrange formula is provided symbolically and numerically. Runge phenomenon is also illustrated. A simple and efficient symbolic derivation of cubic splines is also provided.
Low-power and area-efficient finite field arithmetic architecture based on irreducible all-one polynomials
Mohaghegh, Shima; Muhtaroğlu, Ali; Electrical and Electronics Engineering (2020-9)
This thesis presents a low-power and area-efficient finite field multiplier based on irreducible all-one polynomials (AOP). The proposed organization implements the AOP multiplication algorithm in three stages, which are reduction network, AND network (multiplication), and three input XOR tree (accumulation), while state-of-the-art implementations distribute reduction, multiplication and accumulation operations in a systolic array. The optimization reduces the overall number of sequential elements and provi...
Citation Formats
N. Sipahi Ös, “Algebraic geometric methods in studying splines,” Ph.D. - Doctoral Program, Middle East Technical University, 2013.