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# significandWidth

The number of bits required to represent the value’s significand.

```
var significandWidth: Int { get }
```

## Discussion

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:

- For any representable power of two, `significandWidth` is zero, because
  `significand` is `1.0`.
- If `x` is 10, `x.significand` is `1.01` in binary, so
  `x.significandWidth` is 2.
- If `x` is Float.pi, `x.significand` is `1.10010010000111111011011` in
  binary, and `x.significandWidth` is 23.

---

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