feat: add ln_cdf and ln_sf with tail-accurate implementations - #421

Draft

agene0001 wants to merge 8 commits into

statrs-dev:mainfrom

agene0001:feat/ln-cdf-ln-sf

Commits on Jul 26, 2026

fix: stop prec::ulps_eq! degenerating into a 1e-9 absolute comparison
agene0001
committed
fix: restore full precision to erf's interval constants
agene0001
committed
fix: evaluate the Lanczos sum in a well-conditioned form
agene0001
committed
fix: scale beta_reg's continued-fraction bound with its parameters
agene0001
committed
fix: use Loader's saddle-point form for the gamma/beta prefixes and pmfs
agene0001
committed
merge: erf constant fix, which the tail compensation depends on
agene0001
committed
fix: compensate the argument rounding in Normal's cdf/sf tails
agene0001
committed
feat: add ln_cdf and ln_sf with tail-accurate implementations
agene0001
committed