bladex.ndinterpolator.RBF.thin_plate_spline¶

static RBF.thin_plate_spline(X, r)[source]¶

It implements the following formula:

$\varphi(\| \boldsymbol{x} \|) = \left\| \frac{\boldsymbol{x} }{r} \right\|^2 \ln \left\| \frac{\boldsymbol{x} }{r} \right\|$

Parameters:	X (numpy.ndarray) – l2-norm between given inputs of a function and the locations to perform rbf approximation to that function. r (float) – smoothing length, also called the cut-off radius.
Returns:	result: the result of the formula above.
Return type:	float