SimPEG.regularization.BaseSimilarityMeasure.deriv2

BaseSimilarityMeasure.deriv2(model, v=None)

Second derivative of the coupling term with respect to individual models. Returns either an array of dimensions [k*M,1] (v is not None), or sparse matrix of dimensions [k*M, k*M] (v is None). k: number of models we are inverting for. M: number of cells in each model.