Title:
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A d.c. $C^1$ function need not be difference of convex $C^1$ functions (English) |
Author:
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Pavlica, David |
Language:
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English |
Journal:
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Commentationes Mathematicae Universitatis Carolinae |
ISSN:
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0010-2628 (print) |
ISSN:
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1213-7243 (online) |
Volume:
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46 |
Issue:
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1 |
Year:
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2005 |
Pages:
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75-83 |
. |
Category:
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math |
. |
Summary:
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In [2] a delta convex function on $\Bbb R^2$ is constructed which is strictly differentiable at $0$ but it is not representable as a difference of two convex function of this property. We improve this result by constructing a delta convex function of class $C^1(\Bbb R^2)$ which cannot be represented as a difference of two convex functions differentiable at 0. Further we give an example of a delta convex function differentiable everywhere which is not strictly differentiable at 0. (English) |
Keyword:
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differentiability |
Keyword:
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delta-convex functions |
MSC:
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26B05 |
MSC:
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26B25 |
idZBL:
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Zbl 1121.26011 |
idMR:
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MR2175860 |
. |
Date available:
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2009-05-05T16:49:41Z |
Last updated:
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2012-04-30 |
Stable URL:
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http://hdl.handle.net/10338.dmlcz/119509 |
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Reference:
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[1] Hiriart-Urruty J.-B.: Generalized differentiability, duality and optimization for problem dealing with difference of convex functions.Lecture Notes in Econom. and Math. Systems 256 J. Ponstein, Ed., Springer, Berlin, 1985, pp. 37-70. MR 0873269 |
Reference:
|
[2] Kopecká E., Malý J.: Remarks on delta-convex functions.Comment. Math. Univ. Carolinae 31.3 (1990), 501-510. MR 1078484 |
Reference:
|
[3] Penot J.-P., Bougeard M.L.: Approximation and decomposition properties of some classes of locally d.c. functions.Math. Programming 41 (1988), 195-227. Zbl 0666.49005, MR 0945661 |
Reference:
|
[4] Rockafellar R.T.: Convex Analysis.Princeton University Press, Princeton (1970). Zbl 0193.18401, MR 0274683 |
Reference:
|
[5] Shapiro A.: On functions representable as a difference of two convex functions in inequality constrained optimization.Research report University of South Africa, 1983. |
Reference:
|
[6] Veselý L., Zajíček L.: Delta-convex mappings between Banach spaces and applications.Dissertationes Math. 289 (1989), 1-52. MR 1016045 |
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