Computing the truncated theta function via Mordell integral

Alexey Kuznetsov

Hiary [3] has presented an algorithm which allows to evaluate the truncated theta function ${\sum }_{k=0}^n\exp (2\pi ı(zk+\tau k^2))$ to within $\pm \epsilon$ in $O(\ln (\frac{n}{\epsilon }{)}^{\kappa })$ arithmetic…