4)) { throw new Exception(ExcelError::NAN()); } return $basis; } public static function validatePrice(mixed $price): float { $price = self::validateFloat($price); if ($price < 0.0) { throw new Exception(ExcelError::NAN()); } return $price; } public static function validateParValue(mixed $parValue): float { $parValue = self::validateFloat($parValue); if ($parValue < 0.0) { throw new Exception(ExcelError::NAN()); } return $parValue; } public static function validateYield(mixed $yield): float { $yield = self::validateFloat($yield); if ($yield < 0.0) { throw new Exception(ExcelError::NAN()); } return $yield; } public static function validateDiscount(mixed $discount): float { $discount = self::validateFloat($discount); if ($discount <= 0.0) { throw new Exception(ExcelError::NAN()); } return $discount; } }