significandWidth

var significandWidth: Int { get }

Discussion 解説

If this value is a finite nonzero number, significandWidth is the number of fractional bits required to represent the value of significand; otherwise, significandWidth is -1. The value of significandWidth is always -1 or between zero and significandBitCount. For example: この値が有限の非ゼロ数ならば、significandWidthはsignificandの値を表すのに必要とされる小数部ビットの数です；そうでなければ、significandWidthは-1ですsignificandWidthの値は、常に-1、もしくはゼロとsignificandBitCountの間です。例えば：

• For any representable power of two, significandWidth is zero, because significand is 1.0. あらゆる表現可能な２の冪に対して、significandWidthはゼロです、なぜならsignificandが1.0だからです。

• If x is 10, x.significand is 1.01 in binary, so x.significandWidth is 2. xが10ならば、x.significandは２進数で1.01です、それでx.significandWidthは２です。

• If x is Float.pi, x.significand is 1.10010010000111111011011 in binary, and x.significandWidth is 23. xがFloat.piならば、x.significandは２進数で1.10010010000111111011011です、それでx.significandWidthは23です。