CONTENTS Introduction...........................................................................................................5 I. Canonical complete Chebyshev systems 1. Canonical complete Chebyshev systems.......................................................7 2. Interpolation by generalized polynomials and divided differences................12 3. The Markov inequality for generalized polynomials......................................16 II. Chebyshevian splines 1. Basic properties...........................................................................................18 2. B-splines......................................................................................................21 3. The Marsden identity...................................................................................28 4. De Boor's inequalities..................................................................................32 5. A recurrence relation for B-splines...............................................................37 6. Bounds on zeros..........................................................................................41 III. Spline operators 1. Orthogonal spline projections .....................................................................46 2. Biorthogonal systems..................................................................................49 3. Equivalence of spline bases .......................................................................57 4. Positive spline operators and orthogonal splines .......................................60 IV. Generalized moduli of smoothness and approximation by splines 1. Generalized moduli of smoothness .............................................................64 2. Generalization of the Whitney Theorem.......................................................70 3. Best approximation by splines......................................................................72 4. The Bernstein type inequality for splines ....................................................77 V. Applications to approximation of analytic functions 1. Approximation by analytic splines................................................................78 2. Biorthogonal systems in the complex space A(D)........................................83 3. Systems conjugate to biorthogonal spline systems......................................86 References.........................................................................................................94 List of symbols....................................................................................................98
Institute of Mathematics, Academy of Mining and Metallurgy, Al. Mickiewicza 30, 30-059 Kraków, Poland
Bibliografia
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