Usage
erf(x, mode=0, give=FALSE, strict=TRUE)
erfc(x, mode=0, give=FALSE, strict=TRUE)
log_erfc(x, mode=0, give=FALSE, strict=TRUE)
log_erf_Z(x, mode=0, give=FALSE, strict=TRUE)
erf_Q(x, mode=0, give=FALSE, strict=TRUE)
hazard(x, mode=0, give=FALSE, strict=TRUE)