Wójcik, Paweł Vertices of the unit ball of subspaces in \(\mathcal{L}(H)\) and strong unicity of best approximation in \(\mathcal{L}(l_2^2)\). (English) Zbl 07425717 Linear Algebra Appl. 632, 281-293 (2022). MSC: 46B20 41A35 41A52 41A65 47A58 PDF BibTeX XML Cite \textit{P. Wójcik}, Linear Algebra Appl. 632, 281--293 (2022; Zbl 07425717) Full Text: DOI OpenURL
Wójcik, Paweł Extensions of linear operators from hyperplanes and strong uniqueness of best approximation in \(\mathcal{L}(X, W)\). (English) Zbl 1428.46013 J. Approx. Theory 246, 28-42 (2019). Reviewer: Francisco Pérez Acosta (La Laguna) MSC: 46B20 41A52 41A65 PDF BibTeX XML Cite \textit{P. Wójcik}, J. Approx. Theory 246, 28--42 (2019; Zbl 1428.46013) Full Text: DOI OpenURL
Vijayaragavan, R. Strongly unique best simulations approximation in linear 2-normed spaces. (English) Zbl 1371.41039 Malaya J. Mat. 1, No. 4, 157-162 (2013). MSC: 41A50 41A52 41A99 41A28 PDF BibTeX XML Cite \textit{R. Vijayaragavan}, Malaya J. Mat. 1, No. 4, 157--162 (2013; Zbl 1371.41039) Full Text: Link OpenURL
Micek, A. Constants of strong uniqueness of minimal norm-one projections. (English) Zbl 1234.41017 Hudzik, Henryk (ed.) et al., Function spaces IX. Proceedings of the 9th international conference, Kraków, Poland, July 6–11, 2009. Warszawa: Polish Academy of Sciences, Institute of Mathematics (ISBN 978-83-86806-12-6/pbk). Banach Center Publications 92, 265-277 (2011). MSC: 41A35 41A44 PDF BibTeX XML Cite \textit{A. Micek}, Banach Cent. Publ. 92, 265--277 (2011; Zbl 1234.41017) Full Text: DOI OpenURL
Aksoy, Asuman Güven; Lewicki, Grzegorz Best approximation in numerical radius. (English) Zbl 1222.41026 Numer. Funct. Anal. Optim. 32, No. 6, 593-609 (2011). Reviewer: Vijay Gupta (New Delhi) MSC: 41A35 41A65 47A12 47H10 PDF BibTeX XML Cite \textit{A. G. Aksoy} and \textit{G. Lewicki}, Numer. Funct. Anal. Optim. 32, No. 6, 593--609 (2011; Zbl 1222.41026) Full Text: DOI arXiv Link OpenURL
Kowynia, Joanna The unicity of best approximation in a space of compact operators. (English) Zbl 1208.41022 Bull. Belg. Math. Soc. - Simon Stevin 17, No. 5, 807-820 (2010). Reviewer: Roshdi Khalil (Amman) MSC: 41A65 41A52 PDF BibTeX XML Cite \textit{J. Kowynia}, Bull. Belg. Math. Soc. - Simon Stevin 17, No. 5, 807--820 (2010; Zbl 1208.41022) Full Text: Euclid OpenURL
Kowynia, Joanna Best approximation in Chebyshev subspaces of \({\mathcal L}(l_1^n,l_1^n)\). (English) Zbl 1182.41025 Opusc. Math. 29, No. 1, 57-67 (2009). MSC: 41A50 41A52 41A05 PDF BibTeX XML Cite \textit{J. Kowynia}, Opusc. Math. 29, No. 1, 57--67 (2009; Zbl 1182.41025) Full Text: DOI OpenURL
Odyniec, W.; Prophet, M. P. The strong unicity constant and its applications. (English) Zbl 1149.47009 Hudzik, Henryk (ed.) et al., Function spaces VIII. Proceedings of the 8th conference on function spaces, Bȩdlewo, Poland, July 3–7, 2006. Warsaw: Polish Academy of Sciences, Institute of Mathematics. Banach Center Publications 79, 167-172 (2008). Reviewer: T. D. Narang (Amritsar) MSC: 47A58 41A65 46B20 PDF BibTeX XML Cite \textit{W. Odyniec} and \textit{M. P. Prophet}, Banach Cent. Publ. 79, 167--172 (2008; Zbl 1149.47009) Full Text: Link OpenURL
Lipieta, Agnieszka \(I\)-sets and cominimal projections. (English) Zbl 1184.47004 Ann. Soc. Math. Pol., Ser. I, Commentat. Math. 46, No. 1, 37-62 (2006). MSC: 47A58 41A35 41A65 PDF BibTeX XML Cite \textit{A. Lipieta}, Ann. Soc. Math. Pol., Ser. I, Commentat. Math. 46, No. 1, 37--62 (2006; Zbl 1184.47004) OpenURL
Lipieta, Agnieska The strong unicity constant for projections. (English) Zbl 1135.46008 Zesz. Nauk. Uniw. Jagiell. 1290, Univ. Iagell. Acta Math. 44, 47-68 (2006). Reviewer: Jozef Myjak (L’Aquila) MSC: 46B20 47A58 41A35 41A65 47A30 PDF BibTeX XML Cite \textit{A. Lipieta}, Zesz. Nauk. Uniw. Jagiell., Univ. Iagell. Acta Math. 1290(44), 47--68 (2006; Zbl 1135.46008) Full Text: EuDML OpenURL
Indira, K.; Pai, Devidas Hausdorff strong uniqueness in simultaneous approximation. I. (English) Zbl 1081.41010 Chui, Charles K.(ed.) et al., Approximation theory XI. Proceedings of the 11th international conference, Gatlinburg, TN, USA, May 18–22, 2004. Brentwood, TN: Nashboro Press (ISBN 0-9728482-5-8/hbk). Modern Methods in Mathematics, 345-361 (2005). Reviewer: Daniel Cárdenas-Morales (Jaén) MSC: 41A28 41A50 41A65 PDF BibTeX XML Cite \textit{K. Indira} and \textit{D. Pai}, in: Approximation theory XI. Proceedings of the 11th international conference, Gatlinburg, TN, USA, May 18--22, 2004. Brentwood, TN: Nashboro Press. 345--361 (2005; Zbl 1081.41010) OpenURL
Rao, Geetha S.; Saravanan, R. Strongly unique best coapproximation. (English) Zbl 1086.41013 Kyungpook Math. J. 43, No. 4, 519-538 (2003). Reviewer: J. M. Quesada (Jaen) MSC: 41A50 41A52 41A99 PDF BibTeX XML Cite \textit{G. S. Rao} and \textit{R. Saravanan}, Kyungpook Math. J. 43, No. 4, 519--538 (2003; Zbl 1086.41013) OpenURL
Pai, D. V.; K., Indira Strong unicity in simultaneous approximation. (English) Zbl 1037.41019 Dikshit, H. P. (ed.) et al., Analysis and applications. Outcome of the conference dedicated to Professor Tribikram Pati on the occasion of his 70th birthday, Ujjain, India, 1999. New Delhi: Narosa Publishing House (ISBN 81-7319-470-X/hbk; 0-8493-1721-5/hbk). 207-219 (2002). Reviewer: Daniel Cárdenas-Morales (Jaén) MSC: 41A52 41A28 PDF BibTeX XML Cite \textit{D. V. Pai} and \textit{I. K.}, in: Analysis and applications. Outcome of the conference dedicated to Professor Tribikram Pati on the occasion of his 70th birthday, Ujjain, India, 1999. New Delhi: Narosa Publishing House; Boca Raton, FL: Chapman and Hall/CRC. 207--219 (2002; Zbl 1037.41019) OpenURL
Xu, Hong-Kun; Xu, Zongben Strongly unique best simultaneous approximation in uniformly convex Banach spaces. (English) Zbl 0870.41023 Soochow J. Math. 23, No. 2, 141-155 (1997). MSC: 41A65 46B20 PDF BibTeX XML Cite \textit{H.-K. Xu} and \textit{Z. Xu}, Soochow J. Math. 23, No. 2, 141--155 (1997; Zbl 0870.41023) OpenURL
Lewicki, Grzegorz Strong unicity criterion in some space of operators. (English) Zbl 0785.41023 Commentat. Math. Univ. Carol. 34, No. 1, 81-87 (1993). MSC: 41A65 41A52 41A35 41A50 PDF BibTeX XML Cite \textit{G. Lewicki}, Commentat. Math. Univ. Carol. 34, No. 1, 81--87 (1993; Zbl 0785.41023) Full Text: EuDML OpenURL
Guo, Yuanming Strong uniqueness of nonlinear approximation. (Chinese. English summary) Zbl 0761.41029 J. Math., Wuhan Univ. 11, No. 4, 387-391 (1991). MSC: 41A50 41A65 PDF BibTeX XML Cite \textit{Y. Guo}, J. Math., Wuhan Univ. 11, No. 4, 387--391 (1991; Zbl 0761.41029) OpenURL
Lewicki, Grzegorz Kolmogorov’s type criteria for spaces of compact operators. (English) Zbl 0741.41032 J. Approx. Theory 64, No. 2, 181-202 (1991). Reviewer: G. D. Dikshit (Auckland) MSC: 41A65 46E15 41A50 41A44 PDF BibTeX XML Cite \textit{G. Lewicki}, J. Approx. Theory 64, No. 2, 181--202 (1991; Zbl 0741.41032) Full Text: DOI OpenURL
Xu, Shusheng Strong uniqueness of generalized polynomial of best approximation having bounded coefficients. (English) Zbl 0739.41029 Acta Math. Appl. Sin., Engl. Ser. 7, No. 1, 17-33 (1991). MSC: 41A50 41A10 PDF BibTeX XML Cite \textit{S. Xu}, Acta Math. Appl. Sin., Engl. Ser. 7, No. 1, 17--33 (1991; Zbl 0739.41029) Full Text: DOI OpenURL
Smarzewski, Ryszard Finite extremal characterization of strong uniqueness in normed spaces. (English) Zbl 0733.41035 J. Approximation Theory 62, No. 2, 213-222 (1990). Reviewer: C.Mustăţa (Cluj-Napoca) MSC: 41A65 41A50 PDF BibTeX XML Cite \textit{R. Smarzewski}, J. Approx. Theory 62, No. 2, 213--222 (1990; Zbl 0733.41035) Full Text: DOI OpenURL
Sudolski, J.; Wójcik, A. P. Some remarks on strong uniqueness of best approximation. (English) Zbl 0704.41016 Approximation Theory Appl. 6, No. 2, 44-78 (1990). MSC: 41A50 41A52 PDF BibTeX XML Cite \textit{J. Sudolski} and \textit{A. P. Wójcik}, Approximation Theory Appl. 6, No. 2, 44--78 (1990; Zbl 0704.41016) OpenURL
Smarzewski, Ryszard On nonexistence of strongly unique best approximations. (English) Zbl 0689.41028 J. Math. Anal. Appl. 142, No. 1, 35-39 (1989). Reviewer: A.B.Németh MSC: 41A50 41A65 PDF BibTeX XML Cite \textit{R. Smarzewski}, J. Math. Anal. Appl. 142, No. 1, 35--39 (1989; Zbl 0689.41028) Full Text: DOI OpenURL
Lin, Pei-Kee Strongly unique best approximation in uniformly convex Banach spaces. (English) Zbl 0677.41027 J. Approximation Theory 56, No. 1, 101-107 (1989). Reviewer: P.L.Papini MSC: 41A50 41A65 41A25 41A52 PDF BibTeX XML Cite \textit{P.-K. Lin}, J. Approx. Theory 56, No. 1, 101--107 (1989; Zbl 0677.41027) Full Text: DOI OpenURL
Smarzewski, Ryszard Strong uniqueness of best approximations in an abstract \(L_ 1\) space. (English) Zbl 0675.41048 J. Math. Anal. Appl. 136, No. 2, 347-351 (1988). Reviewer: A.L.Brown MSC: 41A65 41A50 PDF BibTeX XML Cite \textit{R. Smarzewski}, J. Math. Anal. Appl. 136, No. 2, 347--351 (1988; Zbl 0675.41048) Full Text: DOI OpenURL
Smarzewski, Ryszared Strong unicity of best approximations in \(L_{\infty}(S,\Sigma,\mu)\). (English) Zbl 0655.41032 Proc. Am. Math. Soc. 103, No. 1, 113-116 (1988). Reviewer: P.Achuthan MSC: 41A52 46E15 41A45 46E30 PDF BibTeX XML Cite \textit{R. Smarzewski}, Proc. Am. Math. Soc. 103, No. 1, 113--116 (1988; Zbl 0655.41032) Full Text: DOI OpenURL
Kaiser, Ulrich Das Schoenberg’sche Approximationsproblem. (German) Zbl 0647.41009 Universität Mannheim. 97 S. (1987). Reviewer: D.K.Ugulawa MSC: 41A15 41A50 PDF BibTeX XML OpenURL
Nürnberger, Günther Strong unicity in nonlinear parametric optimization. (English) Zbl 0636.90087 Parametric optimization and related topics, Int. Conf., Plaue/GDR 1985, Math. Res. 35, 316-326 (1987). MSC: 90C31 90C30 90C34 PDF BibTeX XML OpenURL
Smarzewski, Ryszard Strong unicity in nonlinear approximation. (English) Zbl 0635.41008 Rational approximation and its applications in mathematics and physics, Proc. Conf., Łańcut/Pol. 1985, Lect. Notes Math. 1237, 331-350 (1987). Reviewer: T.Singh MSC: 41A10 41A50 41A17 41A65 PDF BibTeX XML OpenURL
Nürnberger, Günther Strong unicity constants in Chebyshev approximation. (English) Zbl 0628.41026 Numerical methods of approximation theory, Vol. 8, Workshop Oberwolfach/FRG 1986, ISNM 81, 144-154 (1987). Reviewer: D.Wulbert MSC: 41A50 41A44 41A52 PDF BibTeX XML OpenURL
Brosowski, Bruno; Guerreiro, Claudia On the uniqueness and strong uniqueness of best rational Chebyshev approximation. (English) Zbl 0625.41017 Approximation Theory Appl. 3, No. 1, 49-70 (1987). MSC: 41A50 41A20 PDF BibTeX XML Cite \textit{B. Brosowski} and \textit{C. Guerreiro}, Approximation Theory Appl. 3, No. 1, 49--70 (1987; Zbl 0625.41017) OpenURL
Zwick, D. Strong uniqueness of best spline approximation for a class of piecewise n-convex functions. (English) Zbl 0623.41011 Numer. Funct. Anal. Optimization 9, 371-379 (1987). MSC: 41A15 41A50 41A65 PDF BibTeX XML Cite \textit{D. Zwick}, Numer. Funct. Anal. Optim. 9, 371--379 (1987; Zbl 0623.41011) Full Text: DOI OpenURL
Nürnberger, Günther Strongly unique spline approximations with free knots. (English) Zbl 0621.41008 Constructive Approximation 3, 31-42 (1987). MSC: 41A15 41A52 PDF BibTeX XML Cite \textit{G. Nürnberger}, Constr. Approx. 3, 31--42 (1987; Zbl 0621.41008) Full Text: DOI OpenURL
Nürnberger, Günther Unicity in semi-infinite optimization. (English) Zbl 0586.90065 Parametric optimization and approximation, Conf. Oberwolfach 1983, ISNM 72, 231-247 (1985). MSC: 90C05 90C31 90C34 PDF BibTeX XML OpenURL
Sudolski, Jan; Wójcik, Adam Strong unicity in a quotient space. (English) Zbl 0561.41025 Zesz. Nauk. Uniw. Jagielloń. 661, Pr. Mat. 24, 221-225 (1984). Reviewer: D.Wulbert MSC: 41A50 41A60 PDF BibTeX XML Cite \textit{J. Sudolski} and \textit{A. Wójcik}, Zesz. Nauk. Uniw. Jagielloń. [...], Pr. Mat. 661(24), 221--225 (1984; Zbl 0561.41025) OpenURL
Blatt, Hans-Peter Exchange algorithms, error estimations and strong unicity in convex programming and Chebyshev approximation. (English) Zbl 0553.90085 Approximation theory and spline functions, Proc. NATO Adv. Study Inst., St. John’s/Newfoundland 1983, NATO ASI Ser., Ser. C 136, 23-63 (1984). MSC: 90C30 41A50 65D15 49M37 PDF BibTeX XML OpenURL
Bartelt, Martin W.; Schmidt, Darrell Lipschitz conditions, strong uniqueness, and almost Chebyshev subspaces of C(X). (English) Zbl 0545.41043 J. Approximation Theory 40, 202-215 (1984). Reviewer: T.D.Narang MSC: 41A65 PDF BibTeX XML Cite \textit{M. W. Bartelt} and \textit{D. Schmidt}, J. Approx. Theory 40, 202--215 (1984; Zbl 0545.41043) Full Text: DOI OpenURL
Blatt, Hans-Peter On strong uniqueness in linear Chebyshev approximation. (English) Zbl 0537.41015 J. Approximation Theory 41, 159-169 (1984). MSC: 41A52 41A50 PDF BibTeX XML Cite \textit{H.-P. Blatt}, J. Approx. Theory 41, 159--169 (1984; Zbl 0537.41015) Full Text: DOI OpenURL
Brosowski, B. A refinement of the Kolmogorov criterion. (English) Zbl 0543.41028 Constructive function theory, Proc. int. Conf., Varna/Bulg. 1981, 241-247 (1983). Reviewer: C.G.Lascarides MSC: 41A50 41A65 41A52 PDF BibTeX XML OpenURL
Angelos, James; Schmidt, Darrell Strong uniqueness in \(L^ 1(X,\Sigma,\mu)\). (English) Zbl 0538.41048 Approximation theory IV, Proc. int. Conf., Tex. A&M Univ. 1983, 297-302 (1983). MSC: 41A65 41A52 41A30 PDF BibTeX XML OpenURL
Nürnberger, Günther Strong unicity constants for spline functions. (English) Zbl 0516.41011 Numer. Funct. Anal. Optimization 5, 319-347 (1983). MSC: 41A15 41A50 41A52 PDF BibTeX XML Cite \textit{G. Nürnberger}, Numer. Funct. Anal. Optim. 5, 319--347 (1983; Zbl 0516.41011) Full Text: DOI OpenURL
Nikol’skij, V. N. Boundary sets in a strong sense and the strong uniqueness of elements of the best approximation. (Russian) Zbl 0574.41021 Primen. Funkts. Anal. Teor. Priblizh. 1982, 126-130 (1982). MSC: 41A50 41A52 PDF BibTeX XML OpenURL
Nürnberger, Günther A local version of Haar’s theorem in approximation theory. (English) Zbl 0506.41031 Numer. Funct. Anal. Optimization 5, 21-46 (1982). MSC: 41A52 41A15 41A30 PDF BibTeX XML Cite \textit{G. Nürnberger}, Numer. Funct. Anal. Optim. 5, 21--46 (1982; Zbl 0506.41031) Full Text: DOI OpenURL
Nürnberger, Günther; Singer, Ivan Uniqueness and strong uniqueness of best approximations by spline subspaces and other subspaces. (English) Zbl 0505.41018 J. Math. Anal. Appl. 90, 171-184 (1982). MSC: 41A52 41A15 41A65 PDF BibTeX XML Cite \textit{G. Nürnberger} and \textit{I. Singer}, J. Math. Anal. Appl. 90, 171--184 (1982; Zbl 0505.41018) Full Text: DOI OpenURL
Nürnberger, Günther Unicity and strong unicity in approximation theory. (English) Zbl 0411.41010 J. Approximation Theory 26, 54-70 (1979). MSC: 41A65 41A45 41A50 PDF BibTeX XML Cite \textit{G. Nürnberger}, J. Approx. Theory 26, 54--70 (1979; Zbl 0411.41010) Full Text: DOI OpenURL