‘Spline interpolation using not-a-knot end conditions. The interpolated value at a query point is based on a cubic interpolation of the values at neighboring grid points in each respective dimension.’
It does not appear to be the same as 'cubic'. According to the documentation, 'cubic' is currently the same as 'pchip'.
NSMethod is the Nearest neighbor search method, specified as either 'kdtree' or 'exhaustive'.
'kdtree'— Creates and uses aKd-tree to find nearest neighbors.
'exhaustive'— Uses the exhaustive search algorithm. When predicting the class of a new pointxnew, the algorithm computes the distance values from all points inXtoxnewto find nearest neighbors.
For information on exhaustive and kdtree based searching, you can refer to the following links:
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