Veröffentlichungen "Sommer, Manfred"

Sommer, Manfred:
Property A and best L^1-Approximation.
In: Dolomites research notes on approximation. 12 (2019). - S. 29-37.
ISSN 2035-6803
10.14658/pupj-drna-2019-Special_Issue-5
(Peer-Review-Journal)

Sommer, Manfred:
On the Chebyshev rank of multivariate splines in L^1-approximation.
In: Journal of approximation theory. 164 (2012) 11. - S. 1472-1495.
ISSN 0021-9045
(Peer-Review-Journal)

Sommer, Manfred:
The Chebyshev rank of multivariate polynomials in L1-approximation.
In: Journal of approximation theory. 162 (2010).
ISSN 0021-9045
(Peer-Review-Journal)

Actual problems of control theory, topology and operator equations : International Jubilee Conference at the Kyrgyz-Russian Slavic University Bishkek, Kyrgyzstan, September 15 - 21, 2008.
Hrsg.: Grothmann, René ; Lelevkina, Liliya G. ; Sommer, Manfred
Aachen : Shaker, 2009. - XVI, 203 S. - (Mathematics)
ISBN 978-3-8322-8367-4

Grothmann, René ; Sommer, Manfred:
Composing circular arcs with minimal NURBS.
In: International mathematical forum. 4 (2009) 5-8. - S. 193-218.
ISSN 1312-7594
(Peer-Review-Journal)

Sommer, Manfred:
Interpolation by spline functions.
In: Grothmann, René [Hrsg.]: Actual problems of control theory, topology and operator equations : international jubilee conference at the Kyrgyz-Russian Slavic University Bishkek, Kyrgyzstan, September 15 - 21, 2008. - Aachen : Shaker, 2009. - S. 185-203. - (Mathematics)
ISBN 978-3-8322-8367-4

Sommer, Manfred:
Some remarks on minimal spline interpolation.
In: Applied mathematical sciences. 1 (2007). - S. 1265-1276.
ISSN 1312-885x
(Peer-Review-Journal)

Sommer, Manfred:
Hermite interpolation of data sets by minimal spline spaces.
In: Constructive approximation. 23 (2006). - S. 211-227.
ISSN 0176-4276 ; 1432-0940
(Peer-Review-Journal)

Sommer, Manfred:
Interpolation by uni- and multivariate spline functions.
In: Program Systems : theory and application (Proceedings of an International Conference in Pereslavl-Zalessky, Russia). - Pereslavl-Zalessky, 2006. - S. 337-352
ISBN 5-94052-127-4

Sommer, Manfred:
Characterization of periodic L1-unicity subspaces.
In: Constructive approximation. 21/22 (2005). - S. 95-112.
ISSN 0176-4276 ; 1432-0940
(Peer-Review-Journal)

Sommer, Manfred:
On the Chebyshev rank of differentiable bivariate splines in L1-approximation.
In: International journal of pure and applied mathematics. 23 (2005). - S. 479-490.
ISSN 1311-8080
(Peer-Review-Journal)

Sommer, Manfred:
On the Chebyshev rank of bivariate polynomials and splines in L1-approximation.
In: International journal of pure and applied mathematics. 18 (2005). - S. 503-533.
ISSN 1311-8080
(Peer-Review-Journal)

Analytical and Approximate Methods : International Conference at the Kyrgyz-Russian-Slavic University Bishkek, Kyrgyzstan, September 23-24, 2002.
Hrsg.: Blatt, Hans-Peter ; Felix, Rainer ; Lelevkina, Liliya G. ; Sommer, Manfred
Aachen : Shaker, 2003. - XI, 233 S.
ISBN 3-8322-2147-6

Sommer, Manfred:
Uniqueness of periodic best L^1-approximations.
In: Journal of approximation theory. 123 (2003) 1. - S. 89-109.
ISSN 0021-9045
(Peer-Review-Journal)

Sommer, Manfred:
On best approximation of continuous functions.
In: Blatt, Hans-Peter ; Felix, Rainer ; Lelevkina, Liliya G. ; Sommer, Manfred (Hrsg.): Analytical and Approximate Methods : international conference at the Kyrgyz-Russian-Slavic University Bishkek, Kyrgyzstan, September 23 - 24, 2002. - Aachen : Shaker, 2003. - S. 221-233
ISBN 3-8322-2147-6

Davydov, Oleg ; Sommer, Manfred:
Interpolation by weak Chebyshev spaces.
In: Journal of approximation theory. 102 (2000) 2. - S. 243-262.
ISSN 0021-9045
(Peer-Review-Journal)

Davydov, Oleg ; Sommer, Manfred ; Strauß, Hans:
Interpolation by bivariate linear splines.
In: Journal of computational and applied mathematics. 119 (2000) 1-2. - S. 115-131.
ISSN 0771-050x ; 0377-0427
(Peer-Review-Journal)

Davydov, Oleg ; Sommer, Manfred ; Strauß, Hans:
On almost interpolation and locally linearly independent bases.
In: East journal on approximations. 5 (1999) 1. - S. 67-88.
ISSN 1310-6236
(Peer-Review-Journal)

Davydov, Oleg ; Sommer, Manfred:
Interpolation and almost interpolation by weak Chebyshev spaces.
In: Chui, Charles K. ; Schumaker, Larry L. (Hrsg.): Approximation Theory IX. - Nashville : Vanderbuilt University Press, 1998. - S. 25-32. - (Innovations in applied mathematics)
ISBN 0-8265-1327-1

Davydov, Oleg ; Sommer, Manfred ; Strauß, Hans:
On almost interpolation by multivariate splines.
In: Nürnberger, Günther ; Schmidt, Jochen W. ; Walz, Guido (Hrsg.): Multivariate Approximation and Splines. - Basel : Birkhäuser, 1997. - S. 45-58. - (International Series of Numerical Mathematics ; 125)
ISBN 3-7643-5654-5 ; 0-8176-5654-5

Davydov, Oleg ; Sommer, Manfred ; Strauß, Hans:
Locally linearly independent systems and almost interpolation.
In: Nürnberger, Günther ; Schmidt, Jochen W. ; Walz, Guido (Hrsg.): Multivariate Approximation and Splines. - Basel : Birkhäuser, 1997. - S. 59-72. - (International Series of Numerical Mathematics ; 125)
ISBN 3-7643-5654-5 ; 0-8176-5654-5

Sommer, Manfred ; Strauß, Hans:
A condition of Schoenberg-Whitney type for multivariate spline interpolation.
In: Advances in the theory of computation and computational mathematics : ATCCM. 1 (1996) 5. - S. 381-397.

Sommer, Manfred ; Strauß, Hans:
Totally positive systems and interpolation by subspaces of generalized splines.
In: Gasca, Mariano ; Micchelli, Charles A. (Hrsg.): Total Positivity and its Applications. - Dordrecht : Kluwer, 1996. - S. 85-94. - (Mathematics and its applications ; 359)
ISBN 0-7923-3924-X

Sommer, Manfred ; Strauß, Hans:
Interpolation by uni- and multivariate generalized splines.
In: Journal of approximation theory. 83 (1995) 3. - S. 423-447.
ISSN 0021-9045
(Peer-Review-Journal)

Sommer, Manfred ; Strauß, Hans:
Order of strong uniqueness in best L∞-approximation by spline spaces.
In: Acta mathematica Hungarica. 61 (1993) 3-4. - S. 259-280.
ISSN 0001-5954 ; 0236-5294
10.1007/bf01874685
(Peer-Review-Journal)

Grötzbach, Erwin ; Sommer, Manfred:
Mathematisch-Geographische Fakultät 1980 bis 1993.
In: Müller, Rainer A. (Hrsg.): Veritati et Vitae : Festschrift / im Auftrag der Geschichts- und Gesellschaftswissenschaftlichen Fakultät der Katholischen Universität Eichstätt. Band 2., Vom Bischöflichen Lyzeum zur Katholischen Universität. - Regensburg : Pustet, 1993. - S. 268-274. - (Eichstätter Studien / Neue Folge ; 33,2)
ISBN 3-7917-1376-0

Kroó, András ; Schmidt, Darrell ; Sommer, Manfred:
On A-spaces and their relation to the Hobby-Rice theorem.
In: Journal of approximation theory. 68 (1992) 2. - S. 136-154.
ISSN 0021-9045
(Peer-Review-Journal)

Sommer, Manfred:
Segment approximation using linear functionals.
In: Braess, Dietrich ; Schumaker, Larry L.: (Hrsg.): Numerical Methods of Approximation Theory. Vol. 9. Proceedings of a Conference on Numerical Methods in Approximation Theory which was held at the Mathematisches Forschungsinstitut in Oberwolfach during the week of November 24 - 30, 1991. - Basel : Birkhäuser, 1992. - S. 331-346. - (International Series of Numerical Mathematics ; 105)
ISBN 3-7643-2746-4 ; 0-8176-2746-4

Kroó, András ; Schmidt, Darrell ; Sommer, Manfred:
Some properties of A-spaces and their relationship to L^1-approximation.
In: Constructive approximation. 7 (1991) 1. - S. 329-339.
ISSN 0176-4276 ; 1432-0940
(Peer-Review-Journal)

Sommer, Manfred:
Über eine Rechnerarithmetik mit Ergebnisverifikation.
In: 7. Eichstätter Kolloquium zur Didaktik der Mathematik : 21. Februar 1991. - Eichstätt : Katholische Universität Eichstätt, Mathematisch-Geographische Fakultät, 1991. - S. 1-16

Sommer, Manfred ; Strauß, Hans:
Chebyshev rank in one-sided L^1-approximation.
In: Approximation theory and its applications : ATA. 5 (1989) 4. - S. 79-94.
ISSN 1000-9221
(Peer-Review-Journal)

Sommer, Manfred ; Strauß, Hans:
A characterization of Descartes systems in Haar subspaces.
In: Journal of approximation theory. 57 (1989) 1. - S. 104-116.
ISSN 0021-9045
(Peer-Review-Journal)

Nürnberger, Günther ; Schumaker, Larry L. ; Sommer, Manfred ; Strauß, Hans:
Uniform approximation by generalized splines with free knots.
In: Journal of approximation theory. 59 (1989) 2. - S. 150-169.
ISSN 0021-9045
(Peer-Review-Journal)

Meinardus, Günter ; Nürnberger, Günther ; Sommer, Manfred ; Strauß, Hans:
Algorithms for piecewise polynomials and splines with free knots.
In: Mathematics of computation. 53 (1989) 187. - S. 235-247.
ISSN 0025-5718
(Peer-Review-Journal)

Kroó, András ; Sommer, Manfred ; Strauß, Hans:
On strong uniqueness in one-sided L^1-approximation of differentiable functions.
In: Proceedings of the American Mathematical Society. 106 (1989) 4. - S. 1011-1016.
ISSN 0002-9939 ; 1088-6826
(Peer-Review-Journal)

Sommer, Manfred:
Chebyshev rank of bivariate polynomials in L^1-approximation.
In: Chui, Charles, K. ; Schumaker, Larry L. ; Ward, J. D. (Hrsg.): Approximation Theory VI : proceedings of the Sixth International Symposium on Approximation Theory, held at Texas A & M University on January 9-13, 1989. - Boston : Academic Press, 1989. - S. 597-600
ISBN 0-12-174586-4 ; 0-12-174587-2

Sommer, Manfred ; Strauß, Hans:
Weak Descartes systems in generalized spline spaces.
In: Constructive approximation. 4 (1988) 1. - S. 133-145.
ISSN 0176-4276 ; 1432-0940
(Peer-Review-Journal)

Sommer, Manfred:
Properties of unicity subspaces in L_1-approximation.
In: Journal of approximation theory. 52 (1988) 3. - S. 269-283.
ISSN 0021-9045
(Peer-Review-Journal)

Sommer, Manfred ; Strauß, Hans:
Descartes systems in Haar subspaces.
In: Sendov, Blagovest Ch. ; Petrushev, P. ; Ivanov, K. ; Maleev, R. (Hrsg.): Constructive Theory of Functions : proceedings of the International Conference on Constructive Theory of Functions, Varna, May 24 - May 31, 1987. - Sofia : Publishing House of the Bulgarian Academy of Sciences, 1988. - S. 428-432

Sommer, Manfred:
Examples of unicity subspaces in L_1-approximation.
In: Numerical functional analysis and optimization. 9 (1987) 1-2. - S. 131-146.
ISSN 0163-0563
(Peer-Review-Journal)

Nürnberger, Günther ; Sommer, Manfred ; Strauß, Hans:
An algorithm for segment approximation.
In: Numerische Mathematik. 48 (1986) 4. - S. 463-477.
ISSN 0029-599x
(Peer-Review-Journal)

Sommer, Manfred:
Some properties of unicity subspaces in L_1-approximation.
In: Chui, Charles K. ; Schumaker, Larry L. ; Ward, Joseph D. (Hrsg.): Approximation Theory V : proceedings of the Fifth International Symposium on Approximation Theory, held at Texas A and M University on January 13 - 17, 1986. - Boston : Academic Press, 1986. - S. 563-566
ISBN 0-12-174581-3

Nürnberger, Günther ; Schumaker, Larry L. ; Sommer, Manfred ; Strauß, Hans:
Approximation by generalized splines.
In: Journal of mathematical analysis and applications. 108 (1985) 2. - S. 466-494.
ISSN 0022-247x ; 1096-0813
(Peer-Review-Journal)

Sommer, Manfred:
Parametric approximation by splines.
In: Numerical functional analysis and optimization. 7 (1985) 1. - S. 1-21.
ISSN 0163-0563
(Peer-Review-Journal)

Sommer, Manfred ; Nürnberger, Günther:
Continuous selections in Chebyshev approximation.
In: Brosowski, Bruno ; Deutsch, Frank (Hrsg.): Parametric Optimization and Approximation : conference held at the Mathematisches Forschungsinstitut Oberwolfach, October 16 - 22, 1983. - Basel : Birkhäuser, 1985. - S. 248-263. - (International Series of Numerical Mathematics ; 72)
ISBN 3-7643-1671-3

Sommer, Manfred:
Uniqueness of best L_1-approximations of continuous functions.
In: Meinardus, Günter ; Nürnberger Günther (Hrsg.): Delay Equations, Approximation and Application : International Symposium at the University of Mannheim, October 8–11, 1984. - Basel u.a. : Birkhäuser, 1985. - S. 264-281. - (International Series of Numerical Mathematics ; 74)
ISBN 3-7643-1733-7

Nürnberger, Günther ; Schumaker, Larry L. ; Sommer, Manfred ; Strauß, Hans:
Generalized Tchebycheffian splines.
In: SIAM journal on mathematical analysis. 15 (1984) 4. - S. 790-804.
ISSN 0036-1410 ; 1095-7154
(Peer-Review-Journal)

Sommer, Manfred:
Convergence of best L_p-approximations in subspaces of spline functions.
In: Chui, Charles K. ; Schumaker, Larry L. ; Ward, Joseph D. (Hrsg.): Approximation Theory IV : proceedings of the International Symposium on Approximation Theory, held at Texas A&M University, College Station, Texas, on January 10 - 14, 1983. - New York u.a. : Academic Press, 1984. - S. 685-690
ISBN 0-12-174580-5

Sommer, Manfred:
Weak Chebyshev spaces and best L_1-approximation.
In: Journal of approximation theory. 39 (1983) 1. - S. 54-71.
ISSN 0021-9045
(Peer-Review-Journal)

Sommer, Manfred:
Continuous selections and convergence of best L_p-approximations in subspaces of spline functions.
In: Numerical functional analysis and optimization. 6 (1983) 2. - S. 212-234.
ISSN 0163-0563
(Peer-Review-Journal)

Sommer, Manfred:
Some results on best L_1-approximation of continuous functions.
In: Numerical functional analysis and optimization. 6 (1983) 3. - S. 253-271.
ISSN 0163-0563
(Peer-Review-Journal)

Nürnberger, Günther ; Sommer, Manfred:
A Remez type algorithm for spline functions.
In: Numerische Mathematik. 41 (1983) 1. - S. 117-146.
ISSN 0029-599x
(Peer-Review-Journal)

Nürnberger, Günther ; Schumaker, Larry L. ; Sommer, Manfred ; Strauß, Hans:
Interpolation by generalized splines.
In: Numerische Mathematik. 42 (1983) 2. - S. 195-212.
ISSN 0029-599x
(Peer-Review-Journal)

Nürnberger, Günther ; Sommer, Manfred:
Alternation for best spline approximations.
In: Numerische Mathematik. 41 (1983) 2. - S. 207-221.
ISSN 0029-599x
(Peer-Review-Journal)

Sommer, Manfred:
L_p-approximations and Chebyshev approximations in subspaces of spline functions.
In: Brosowski, Bruno ; Martensen, Erich (Hrsg.): Approximation and optimization in mathematical physics : papers presented to the 10th Conference on Methoden und Verfahren der Mathematischen Physik, held on February 21 - 27, 1982 at the Mathematisches Forschungsinstitut Oberwolfach. - Frankfurt am Main : Lang, 1983. - S. 105-139. - (Methoden und Verfahren der mathematischen Physik ; 27)
ISBN 3-8204-7631-8

Sommer, Manfred:
Existence of pointwise-Lipschitz-continuous selections of the metric projection for a class of Z-spaces.
In: Journal of approximation theory. 34 (1982) 2. - S. 115-130.
ISSN 0021-9045
(Peer-Review-Journal)

Sommer, Manfred:
Finite dimensional subspaces and alternation.
In: Journal of approximation theory. 34 (1982) 2. - S. 131-145.
ISSN 0021-9045
(Peer-Review-Journal)

Sommer, Manfred ; Strauß, Hans:
Unicity of best one-sided L_1-approximations for certain classes of spline functions.
In: Numerical functional analysis and optimization. 4 (1982) 4. - S. 413-435.
ISSN 0163-0563
(Peer-Review-Journal)

Sommer, Manfred:
Characterization of continuous selections of the metric projection for a class of weak Chebyshev spaces.
In: SIAM journal on mathematical analysis. 13 (1982) 2. - S. 280-294.
ISSN 0036-1410 ; 1095-7154
(Peer-Review-Journal)

Blatt, Hans-Peter ; Nürnberger, Günther ; Sommer, Manfred:
A characterization of pointwise-Lipschitz-continuous selections for the metric projection.
In: Numerical functional analysis and optimization. 4 (1981). - S. 101-121.
ISSN 0163-0563
(Peer-Review-Journal)

Sommer, Manfred:
Characterization of continuous selections for the metric projection for generalized splines.
In: SIAM journal on mathematical analysis. 11 (1980) 1. - S. 23-40.
ISSN 0036-1410 ; 1095-7154
(Peer-Review-Journal)

Sommer, Manfred:
Nonexistence of continuous selections of the metric projection for a class of weak Chebyshev spaces.
In: Transactions of the American Mathematical Society. 260 (1980). - S. 403-409.
ISSN 0002-9947
(Peer-Review-Journal)

Blatt, Hans-Peter ; Nürnberger, Günther ; Sommer, Manfred:
Pointwise-Lipschitz-continuous selections for the metric projection.
In: Cheney, Elliot W. (Hrsg.): Approximation Theory III : proceedings of a Conference Honoring Professor George G. Lorentz, held at the University of Texas at Austin January 8 - 12, 1980. - New York : Academic Press, 1980. - S. 223-228
ISBN 0-12-171050-5

Sommer, Manfred:
Continuous selections for metric projections.
In: Devore, Ronald A. ; Scherer, Karl (Hrsg.): Quantitative Approximation : proceedings of a Symposium held in Bonn, West germany, August 20 - 24, 1979. - New York : Academic Press, 1980. - S. 301-317
ISBN 0-12-213650-0

Sommer, Manfred:
Continuous selections of the metric projection for 1-Chebyshev spaces.
In: Journal of approximation theory. 26 (1979) 1. - S. 46-53.
ISSN 0021-9045
(Peer-Review-Journal)

Sommer, Manfred:
L_1-approximation by weak Chebyshev spaces.
In: Meinardus, Günter (Hrsg.): Approximation in Theorie und Praxis : ein Symposiumsbericht. - Mannheim u.a. : Bibliographisches Institut, 1979. - S. 85-102
ISBN 3-411-01567-5

Nürnberger, Günther ; Sommer, Manfred:
Characterization of continuous selections of the metric projection for spline functions.
In: Journal of approximation theory. 22 (1978) 4. - S. 320-330.
ISSN 0021-9045
(Peer-Review-Journal)

Nürnberger, Günther ; Sommer, Manfred:
Weak Chebyshev subspaces and continuous selections for the metric projection.
In: Transactions of the American Mathematical Society. 238 (1978). - S. 129-138.
ISSN 0002-9947
(Peer-Review-Journal)

Sommer, Manfred ; Strauß, Hans:
Eigenschaften von schwach tschebyscheffschen Räumen.
In: Journal of approximation theory. 21 (1977) 3. - S. 257-268.
ISSN 0021-9045
(Peer-Review-Journal)

Sommer, Manfred:
Alternanten bei gleichmäßiger Approximation mit zweidimensionalen Splinefunktionen.
In: Böhmer, Klaus ; Meinardus, Günter ; Schempp, Walter (Hrsg.): Spline Functions : proceedings of an international symposium held at Karlsruhe, Germany, May 20 - 23, 1975. - Berlin ; Heidelberg ; New York : Springer, 1976. - S. 339-370. - (Lecture notes in mathematics ; 501)
ISBN 3-540-07543-7 ; 0-387-07543-7

Sommer, Manfred:
Charakterisierung von Minimallösungen in normierten Vektorräumen durch Eigenschaften von Hyperebenen.
In: Journal of approximation theory. 14 (1975) 2. - S. 103-114.
ISSN 0021-9045
(Peer-Review-Journal)