| |
| |
Preface | |
| |
| |
| |
The approximation problem and existence of best approximations | |
| |
| |
| |
Examples of approximation problems | |
| |
| |
| |
Approximation in a metric space | |
| |
| |
| |
Approximation in a normed linear space | |
| |
| |
| |
The L[subscript p]-norms | |
| |
| |
| |
A geometric view of best approximations | |
| |
| |
| |
The uniqueness of best approximations | |
| |
| |
| |
Convexity conditions | |
| |
| |
| |
Conditions for the uniqueness of the best approximation | |
| |
| |
| |
The continuity of best approximation operators | |
| |
| |
| |
The 1-, 2- and [infinity]-norms | |
| |
| |
| |
Approximation operators and some approximating functions | |
| |
| |
| |
Approximation operators | |
| |
| |
| |
Lebesgue constants | |
| |
| |
| |
Polynomial approximations to differentiable functions | |
| |
| |
| |
Piecewise polynomial approximations | |
| |
| |
| |
Polynomial interpolation | |
| |
| |
| |
The Lagrange interpolation formula | |
| |
| |
| |
The error in polynomial interpolation | |
| |
| |
| |
The Chebyshev interpolation points | |
| |
| |
| |
The norm of the Lagrange interpolation operator | |
| |
| |
| |
Divided differences | |
| |
| |
| |
Basic properties of divided differences | |
| |
| |
| |
Newton's interpolation method | |
| |
| |
| |
The recurrence relation for divided differences | |
| |
| |
| |
Discussion of formulae for polynomial interpolation | |
| |
| |
| |
Hermite interpolation | |
| |
| |
| |
The uniform convergence of polynomial approximations | |
| |
| |
| |
The Weierstrass theorem | |
| |
| |
| |
Monotone operators | |
| |
| |
| |
The Bernstein operator | |
| |
| |
| |
The derivatives of the Bernstein approximations | |
| |
| |
| |
The theory of minimax approximation | |
| |
| |
| |
Introduction to minimax approximation | |
| |
| |
| |
The reduction of the error of a trial approximation | |
| |
| |
| |
The characterization theorem and the Haar condition | |
| |
| |
| |
Uniqueness and bounds on the minimax error | |
| |
| |
| |
The exchange algorithm | |
| |
| |
| |
Summary of the exchange algorithm | |
| |
| |
| |
Adjustment of the reference | |
| |
| |
| |
An example of the iterations of the exchange algorithm | |
| |
| |
| |
Applications of Chebyshev polynomials to minimax approximation | |
| |
| |
| |
Minimax approximation on a discrete point set | |
| |
| |
| |
The convergence of the exchange algorithm | |
| |
| |
| |
The increase in the levelled reference error | |
| |
| |
| |
Proof of convergence | |
| |
| |
| |
Properties of the point that is brought into reference | |
| |
| |
| |
Second-order convergence | |
| |
| |
| |
Rational approximation by the exchange algorithm | |
| |
| |
| |
Best minimax rational approximation | |
| |
| |
| |
The best approximation on a reference | |
| |
| |
| |
Some convergence properties of the exchange algorithm | |
| |
| |
| |
Methods based on linear programming | |
| |
| |
| |
Least squares approximation | |
| |
| |
| |
The general form of a linear least squares calculation | |
| |
| |
| |
The least squares characterization theorem | |
| |
| |
| |
Methods of calculation | |
| |
| |
| |
The recurrence relation for orthogonal polynomials | |
| |
| |
| |
Properties of orthogonal polynomials | |
| |
| |
| |
Elementary properties | |
| |
| |
| |
Gaussian quadrature | |
| |
| |
| |
The characterization of orthogonal polynomials | |
| |
| |
| |
The operator R[subscript n] | |
| |
| |
| |
Approximation to periodic functions | |
| |
| |
| |
Trigonometric polynomials | |
| |
| |
| |
The Fourier series operator S[subscript n] | |
| |
| |
| |
The discrete Fourier series operator | |
| |
| |
| |
Fast Fourier transforms | |
| |
| |
| |
The theory of best L[subscript 1] approximation | |
| |
| |
| |
Introduction to best L[subscript 1] approximation | |
| |
| |
| |
The characterization theorem | |
| |
| |
| |
Consequences of the Haar condition | |
| |
| |
| |
The L[subscript 1] interpolation points for algebraic polynomials | |
| |
| |
| |
An example of L[subscript 1] approximation and the discrete case | |
| |
| |
| |
A useful example of L[subscript 1] approximation | |
| |
| |
| |
Jackson's first theorem | |
| |
| |
| |
Discrete L[subscript 1] approximation | |
| |
| |
| |
Linear programming methods | |
| |
| |
| |
The order of convergence of polynomial approximations | |
| |
| |
| |
Approximations to non-differentiable functions | |
| |
| |
| |
The Dini-Lipschitz theorem | |
| |
| |
| |
Some bounds that depend on higher derivatives | |
| |
| |
| |
Extensions to algebraic polynomials | |
| |
| |
| |
The uniform boundedness theorem | |
| |
| |
| |
Preliminary results | |
| |
| |
| |
Tests for uniform convergence | |
| |
| |
| |
Application to trigonometric polynomials | |
| |
| |
| |
Application to algebraic polynomials | |
| |
| |
| |
Interpolation by piecewise polynomials | |
| |
| |
| |
Local interpolation methods | |
| |
| |
| |
Cubic spline interpolation | |
| |
| |
| |
End conditions for cubic spline interpolation | |
| |
| |
| |
Interpolating splines of other degrees | |
| |
| |
| |
B-splines | |
| |
| |
| |
The parameters of a spline function | |
| |
| |
| |
The form of B-splines | |
| |
| |
| |
B-splines as basis functions | |
| |
| |
| |
A recurrence relation for B-splines | |
| |
| |
| |
The Schoenberg-Whitney theorem | |
| |
| |
| |
Convergence properties of spline approximations | |
| |
| |
| |
Uniform convergence | |
| |
| |
| |
The order of convergence when f is differentiable | |
| |
| |
| |
Local spline interpolation | |
| |
| |
| |
Cubic splines with constant knot spacing | |
| |
| |
| |
Knot positions and the calculation of spline approximations | |
| |
| |
| |
The distribution of knots at a singularity | |
| |
| |
| |
Interpolation for general knots | |
| |
| |
| |
The approximation of functions to prescribed accuracy | |
| |
| |
| |
The Peano kernel theorem | |
| |
| |
| |
The error of a formula for the solution of differential equations | |
| |
| |
| |
The Peano kernel theorem | |
| |
| |
| |
Application to divided differences and to polynomial interpolation | |
| |
| |
| |
Application to cubic spline interpolation | |
| |
| |
| |
Natural and perfect splines | |
| |
| |
| |
A variational problem | |
| |
| |
| |
Properties of natural splines | |
| |
| |
| |
Perfect splines | |
| |
| |
| |
Optimal interpolation | |
| |
| |
| |
The optimal interpolation problem | |
| |
| |
| |
L[subscript 1] approximation by B-splines | |
| |
| |
| |
Properties of optimal interpolation | |
| |
| |
| |
The Haar condition | |
| |
| |
| |
Related work and references | |
| |
| |
Index | |