The Cross-in-Tray function has multiple global minima. It is shown here with a smaller domain in the second plot, so that its characteristic "cross" will be visible.
Input Domain:The function is usually evaluated on the square xi ∈ [-10, 10], for all i = 1, 2.
Test functions for optimization. In Wikipedia. Retrieved June 2013, from https://en.wikipedia.org/wiki/Test_functions_for_optimization.
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