sainsc.utils.epanechnikov_kernel
================================

.. py:function:: sainsc.utils.epanechnikov_kernel(bw, *, dtype = np.float32)

   Generate a 2D Epanechnikov kernel array.

   :math:`K(x) = 1/2 * c_d^{-1}*(d+2)(1-||x||^2)` if :math:`||x|| < 1` else 0,
   where :math:`d` is the number of dimensions
   and :math:`c_d` the volume of the unit `d`-dimensional sphere.

   :param bw: Bandwidth of the kernel.
   :type bw: float
   :param dtype: Datatype of the kernel.
   :type dtype: numpy.typing.DTypeLike, optional

   :rtype: numpy.ndarray