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# init(mantissa:exponent:isNegative:)

Initializes a decimal number using the given mantissa, exponent, and sign.

```
convenience init(mantissa: UInt64, exponent: Int16, isNegative flag: Bool)
```

## Parameters

`mantissa`

The mantissa for the new decimal number object.

`exponent`

The exponent for the new decimal number object.

`flag`

A Boolean value that specifies whether the sign of the number is negative.

## Return Value

An `NSDecimalNumber` object initialized using the given mantissa, exponent, and sign.

## Discussion

The arguments express a number in a type of scientific notation that requires the mantissa to be an integer. So, for example, if the number to be represented is 1.23, it is expressed as 123x10^–2—`mantissa` is 123; `exponent` is –2; and `isNegative`, which refers to the sign of the mantissa, is <doc://com.apple.documentation/documentation/Swift/false>.

## See Also

[`+  decimalNumberWithMantissa:exponent:isNegative:`](/documentation/Foundation/NSDecimalNumber/decimalNumberWithMantissa:exponent:isNegative:)

Creates and returns a decimal number equivalent to the number specified by the arguments.


---

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