Abstract convexity of topical functions

In this paper, we examine properties of topical (increasing and plus-homogeneous) functions defined on a normed linear space <InlineEquation ID="IEq1"> <EquationSource Format="TEX">$${X}$$</EquationSource> </InlineEquation>. We also study many results of abstract convexity such as support set, polarity and subdifferential set of these functions. Finally, we give a characterization for topical functions with respect to closed downward sets. Copyright Springer Science+Business Media New York 2014