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ModuleDeformations :: deformMCMModule(..., DegreeLimit => ...)

deformMCMModule(..., DegreeLimit => ...) -- Compute only up to this exponent

Description

This parameter is an integer n such that in the result of the computation the versality criterion holds only after reducing the relevant rings modulo the maximal homogeneous ideal to the power n+1 . Concretely, this means that the output may have incorrect terms with total exponent greater than n . If the input is positively graded, all deformation parameters have strictly positive degree, and n is sufficently large, then no terms of degree greater than n appear in the output, and the result is versal. In this case, the maximum of d / deg x where d is the degree of the equation of the hypersurface and x ranges over all variables in the ring of the hypersurface and all deformation parameters, should suffice.

Further information