spectralbrain.shape_difference_operator#

spectralbrain.shape_difference_operator(C, *, type='area')[source]#

Compute a shape-difference operator from a functional map.

Parameters:

C (ndarray, shape (k, k)) – Functional map from shape A to shape B.
type (str) – "area" — D_area = C^T · C (captures area distortion). "conformal" — D_conf = C^T · Λ_B · C · Λ_A^{-1} (simplified: uses C^T · C − I to capture conformal distortion).

Returns:

D (ndarray, shape (k, k)) – Shape-difference operator (symmetric positive semi-definite for area type).

Return type:

ndarray

References

Rustamov RM, Ovsjanikov M, Azencot O, Ben-Chen M, Chazal F, Guibas LJ. Map-based exploration of intrinsic shape differences and variability. ACM TOG 32(4):72, 2013.