- Given any masks for any d-refinable function vectors, compute the critical exponent of the mask.
- The critical expoenent is closely related to the smoothness of the refinable function. In general, if , then the cascade algorithm converges

in the Sobolev space - This program is based on the following paper (Theorem 7.1):

Bin Han, "Vector cascade algorithms and refinable function vectors in Sobolev spaces", Journal of Approximation Theory, Volumn 124 (2003), Issue 1, 44-88.

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