randomLineTorsZ5(d1',relPfaf)
The order of the torsion group does only depend on the choice of the line in the complete intersection of the quadratic relations $Q$ in $\mathbb{P}^{11}$. A numerical Godeaux surface $X$ with torsion group $\mathbb{Z}/5$ has two special reducible curves in the bicanonical system. These curves are for the form $D_1+D_4$ and $D_2+D_3$, where $D_i \in |K_X + t_i|$ for a torsion element $t_i$ of order $i$. To construct a surface with such curves, the associated line $l$ must intersect each of two different loci in $Q$ in exactly one point. These loci are computed in the procedure lineConditionsTorsZ5.
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The object randomLineTorsZ5 is a method function with options.