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# -(_:_:)

Subtracts one value from another and produces their difference, rounded
to a representable value.

```
static func - (lhs: Float, rhs: Float) -> Float
```

## Parameters

`lhs`

A numeric value.

`rhs`

The value to subtract from `lhs`.

## Discussion

The subtraction operator (`-`) calculates the difference of its two
arguments. For example:

```
let x = 7.5
let y = x - 2.25
// y == 5.25
```

The `-` operator implements the subtraction operation defined by the
[IEEE 754 specification](http://ieeexplore.ieee.org/servlet/opac?punumber=4610933).

---

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