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RelativeCanonicalResolution :: lineBundleFromPointsAndMultipliers

lineBundleFromPointsAndMultipliers -- Computes basis of a line bundle from the 2g points P_i, Q_i and the multipliers

Synopsis

Description

If C is a g-nodal canonical curve with normalization ν: P1 →Pg-1 then a line bundle L of degree k on C is given by ν*(OP1(k))≅L and gluing data (bj)/(aj):OP1⊗kk(Pj)→OP1⊗kk(Qj). Given 2g points Pi, Qi and the multipliers (ai,bi) we can compute a basis of sections of L as a kernel of the matrix A=(A)ij with Aij=biBj(Pi)-aiBj(Qi) where Bj:P1→kk, (p0:p1)→p0k-jp1j.

See also

Ways to use lineBundleFromPointsAndMultipliers :