Unicity of Best One-Sided L1-Approximations with Applications to Moment Theory and Quadrature Formulae

  • Hans Strauß
Part of the ISNM 57: International Series of Numerical Mathematics / Internationale Schriftenreihe zur Numerischen Mathematik / Série internationale d’Analyse numérique book series (ISNM, volume 57)


Let C(I) be the linear space of all real-valued functions defined on I=[0,1] and let G denote an n-dimensional subspace of C(I). First we shall study best one-sided L1-approximation for all functions f in C(I). Existence is readily shown. Therefore we shall concern ourselves with the question of uniqueness. This approximation problem has an important application to numerical integration since it is closely related to the existence and uniqueness of quadrature formulae of highest possible degree of precision (in particular, formulae of Gauss type).


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© Springer Basel AG 1982

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  • Hans Strauß

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