The Cross-In-Tray function looks like:
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Cross-In-Tray Function
The Cross-In-Tray function looks like:
Dimensions: 2
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.
The function is usually evaluated on the xi ∈ [-10, 10] square, for all i = 1, 2.