Abstract
Convexity plays a prominent role in a number of areas, but practical considerations often lead to nonconvex functions. We suggest a method for determining regions of convexity and also for assessing the lack of convexity of functions in the other regions. The method relies on a specially constructed decomposition of symmetric matrices. Illustrative examples accompany theoretical results.
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Dedicated to Professor Vygantas Paulauskas, our dear friend, colleague, untiring researcher, and inspiring teacher
*The research has been supported by a grant from the Natural Sciences and Engineering Research Council (NSERC) of Canada and the National Research Organization “Mathematics of Information Technology and Complex Systems” (MITACS) of Canada.
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Davydov, Y., Moldavskaya, E. & Zitikis, R. Searching for and Quantifying Nonconvexity Regions of Functions*. Lith Math J 59, 507–518 (2019). https://doi.org/10.1007/s10986-019-09465-6
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DOI: https://doi.org/10.1007/s10986-019-09465-6