betti(C, Minimize => true)
Given a chain complex computed using res(I, FastNonminimal => true) (FastNonminimal), returns the minimal graded Betti numbers of this complex.
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For a non-minimal resolution, betti gives the actual ranks of the complex. If the option Minimize => true is given, the minimal Betti numbers are returned.
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This command is useful if the non-minimal free resolution has already been computed. However, to get the minimal betti numbers of an ideal or module, it is recommended to use the function minimalBetti as that avoids much computation and allows the use of length and degree limits.
Released in M2 1.9, still experimental. Only works over finite prime field. If the complex is the resolution of a non-homogeneous or multi-homogeneous object, then this function will result in an error.