public static function CDF($x, $μ, $σ) { Support::checkLimits(self::LIMITS, ['x' => $x, 'μ' => $μ, 'σ' => $σ]); $π = \M_PI; $⟮ln x − μ⟯ = log($x) - $μ; $√2σ = sqrt(2) * $σ; return 1 / 2 + 1 / 2 * Special::erf($⟮ln x − μ⟯ / $√2σ); }