Journal of Approximation Theory

Aims & Scope

The Journal of Approximation Theory is devoted to advances in pure and applied approximation theory and related areas.

These areas include, among others: • Classical approximation • Abstract approximation • Constructive approximation • Degree of approximation • Fourier expansions • Interpolation of operators • General orthogonal systems • Interpolation and quadratures • Multivariate approximation • Orthogonal polynomials • Padé approximation • Rational approximation • Spline functions of one and several variables • Approximation by radial basis functions in Euclidean spaces, on spheres, and on more general manifolds • Special functions with strong connections to classical harmonic analysis, orthogonal polynomial, and approximation theory (as opposed to combinatorics, number theory, representation theory, generating functions, formal theory, and so forth) • Approximation theoretic aspects of real or complex function theory, function theory, difference or differential equations, function spaces, or harmonic analysis • Wavelet Theory and its applications in signal and image processing, and in differential equations with special emphasis on connections between wavelet theory and elements of approximation theory (such as approximation orders, Besov and Sobolev spaces, and so forth) • Gabor (Weyl-Heisenberg) expansions and sampling theory.

View Aims & Scope

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Metrics & Ranking

Journal Rank

Year	Value
2024	10530

Journal Citation Indicator

Year	Value
2024	148

SJR (SCImago Journal Rank)

Year	Value
2024	0.553

Quartile

Year	Value
2024	Q2

h-index

Year	Value
2024	59

Impact Factor

Year	Value
2024	0.90

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Abstracting & Indexing

Journal is indexed in leading academic databases, ensuring global visibility and accessibility of our peer-reviewed research.

• Scopus
• Google Scholar
• Web of Science

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Subjects & Keywords

Journal’s research areas, covering key disciplines and specialized sub-topics in Mathematics, designed to support cutting-edge academic discovery.

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Most Cited Articles

The Most Cited Articles section features the journal's most impactful research, based on citation counts. These articles have been referenced frequently by other researchers, indicating their significant contribution to their respective fields.

• On calculating with B-splines

  Citation: 1458

  Authors: Carl

• Fractal Functions and Wavelet Expansions Based on Several Scaling Functions

  Citation: 465

  Authors: J.S., D.P., P.R.

• A strong convergence theorem for relatively nonexpansive mappings in a Banach space

  Citation: 300

  Authors: Shin-ya, Wataru

• Géza Freud, orthogonal polynomials and Christoffel functions. A case study

  Citation: 294

  Authors: Paul

• Error Estimates for Interpolation by Compactly Supported Radial Basis Functions of Minimal Degree

  Citation: 267

  Authors: Holger

• Spline approximation by quasiinterpolants

  Citation: 267

  Authors: C, G.J

• The calculus of fractal interpolation functions

  Citation: 225

  Authors: Michael F, Andrew N

• Finite approximation for the Frobenius-Perron operator. A solution to Ulam's conjecture

  Citation: 211

  Authors: Tien-Yien

• Optimal error bounds for cubic spline interpolation

  Citation: 210

  Authors: Charles A, W.Weston

• Approximating Solutions of Maximal Monotone Operators in Hilbert Spaces

  Citation: 204

  Authors: Shoji, Wataru

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