When casting a value of type xs: float or xs: double, or any one of their subtypes, to a string or untypedAtomic type, the value is represented in scientific notation.

• 将xs:float或xs:double类型或者它们任意子类型的值转换为字符串类型或untypedAtomic类型的值时,该值将以科学记数法表示。