Title
Well-conditioned fractional collocation methods using fractional Birkhoff interpolation basis.
Abstract
The purpose of this paper is twofold. Firstly, we provide explicit and compact formulas for computing both Caputo and (modified) Riemann–Liouville (RL) fractional pseudospectral differentiation matrices (F-PSDMs) of any order at general Jacobi–Gauss–Lobatto (JGL) points. We show that in the Caputo case, it suffices to compute F-PSDM of order μ∈(0,1) to compute that of any order k+μ with integer k≥0, while in the modified RL case, it is only necessary to evaluate a fractional integral matrix of order μ∈(0,1). Secondly, we introduce suitable fractional JGL Birkhoff interpolation problems leading to new interpolation polynomial basis functions with remarkable properties: (i) the matrix generated from the new basis yields the exact inverse of F-PSDM at “interior” JGL points; (ii) the matrix of the highest fractional derivative in a collocation scheme under the new basis is diagonal; and (iii) the resulted linear system is well-conditioned in the Caputo case, while in the modified RL case, the eigenvalues of the coefficient matrix are highly concentrated. In both cases, the linear systems of the collocation schemes using the new basis can be solved by an iterative solver within a few iterations. Notably, the inverse can be computed in a very stable manner, so this offers optimal preconditioners for usual fractional collocation methods for fractional differential equations (FDEs). It is also noteworthy that the choice of certain special JGL points with parameters related to the order of the equations can ease the implementation. We highlight that the use of the Bateman's fractional integral formulas and fast transforms between Jacobi polynomials with different parameters, is essential for our algorithm development.
Year
DOI
Venue
2016
10.1016/j.jcp.2015.10.029
Journal of Computational Physics
Keywords
Field
DocType
Fractional differential equations,Caputo fractional derivative,(Modified) Riemann–Liouville fractional derivative,Fractional Birkhoff interpolation,Interpolation basis polynomials,Well-conditioned collocation methods
Mathematical optimization,Coefficient matrix,Matrix (mathematics),Mathematical analysis,Interpolation,Jacobi polynomials,Fractional calculus,Birkhoff interpolation,Mathematics,Eigenvalues and eigenvectors,Collocation
Journal
Volume
Issue
ISSN
305
C
0021-9991
Citations 
PageRank 
References 
7
0.55
19
Authors
3
Name
Order
Citations
PageRank
Yujian Jiao181.26
Li-Lian Wang236743.47
Can Huang3142.42