Detector.surface_measure

Detector.surface_measure(self, param)

Density function of the surface measure.

This is the default implementation relying on the surface_deriv method. For a detector with ndim equal to 1, the density is given by the Arc length, for a surface with ndim 2 in a 3D space, it is the length of the cross product of the partial derivatives of the parametrization, see Wikipedia’s Surface area article.

Parameters

paramarray-like or sequence

Parameter value(s) at which to evaluate. If ndim >= 2, a sequence of length ndim must be provided.

Returns

measurefloat or numpy.ndarray

The density value(s) at the given parameter(s). If a single parameter is provided, a float is returned. Otherwise, an array is returned with shape

• param.shape if ndim is 1,

• broadcast(*param).shape otherwise.

References