In He (2021), I present a new analytic method for calculating galaxy two-point correlation functions (TPCFs) that is accurate, efficient, and applicable to surveys with regular geometries. Closed-form formulas are derived for the normalized random-random pair counts RR for rectangular, cuboidal, circular and spherical survey volumes. Algorithms are also suggested to compute the normalized data-random pair counts DR analytically by fully accounting for edge effects. When tested on a galaxy catalog from the EAGLE simulation, this new analytic method computes RR and DR with perfect accuracy and zero variance, with speeds 3-6 orders of magnitude faster than Monte Carlo methods and 2.5 orders of magnitude faster than tree-based algorithms. For surveys with masks, irregular shapes or weighted patterns, the method is limited, but it provides significant speed improvements for basic TPCF calculations .
