Abstract
We complete the study of the convexity of the proximal average by proving it is convex as a function of each of its parameters separately, but not jointly convex as a function of any two of its parameters. We present an interpolation-based plotting algorithm that takes advantage of the partial convexity of the proximal average, and improves the plotting time by a factor of 100, while reducing picture sizes by a factor of 10.
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Communicated by F. Zirilli.
The authors would like to thank Dr. Mason Macklem for his carefully reading of the manuscript. Yves Lucet was partially supported by a Discovery grant from the Natural Sciences and Engineering Research Council of Canada. Valentin Koch was partially supported by the Ministry of Advanced Education of the province of British Columbia through a Pacific Century Graduate Scholarship.
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Johnstone, J.A., Koch, V.R. & Lucet, Y. Convexity of the Proximal Average. J Optim Theory Appl 148, 107–124 (2011). https://doi.org/10.1007/s10957-010-9747-5
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DOI: https://doi.org/10.1007/s10957-010-9747-5