SiegelTheta
SiegelTheta[Ω,s] gives the Siegel theta function Θ (Ω,s) with Riemann modular matrix Ω and vector s.
SiegelTheta[{ν1,ν2},Ω,s] gives the Siegel theta function Θ [ν1,ν2]( Ω,s) with characteristics ν1 and ν2.
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