What exactly is "zoom"? about zoomgrid

[yukai-yang]

Hello!

Thank you for the comments! And sorry for the late reply! Just answer the questions in the following:

1. it is the standard grid search with some extension, definitely not random.
2. "zoom" means "zoom in". Yes, the algorithm can "zoom in" in the sense that it will take a closer look at the neighbourhood of some points if the optimum is believed to be somewhere around there.
3. I think yes, because the "constraints" in most cases can be regarded as "boundaries", and then we don't need to consider the points outside the "boundaries".
4. Definitely yes. The algorithm does not rely on derivatives (derivative free optimization).