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# significantDigits(_:)

Returns a precision that constrains formatted values to a given number of significant digits.

```
static func significantDigits(_ digits: Int) -> NumberFormatStyleConfiguration.Precision
```

## Parameters

`digits`

The maximum number of significant digits to use when formatting values.

## Return Value

A precision that constrains formatted values to a given number of significant digits.

## Discussion

When using this precision, the formatter rounds values that have more sigificant digits than the maximum of the range, as seen in the following example:

```swift
let myNum = 123456.formatted(.number
    .precision(.significantDigits(4))
    .rounded(rule: .down)) // "123,400"
```

---

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