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# formRemainder(dividingBy:)

Replaces this value with the remainder of itself divided by the given
value.

```
mutating func formRemainder(dividingBy other: Float)
```

## Parameters

`other`

The value to use when dividing this value.

## Discussion

For two finite values `x` and `y`, the remainder `r` of dividing `x` by
`y` satisfies `x == y * q + r`, where `q` is the integer nearest to
`x / y`. If `x / y` is exactly halfway between two integers, `q` is
chosen to be even. Note that `q` is *not* `x / y` computed in
floating-point arithmetic, and that `q` may not be representable in any
available integer type.

The following example calculates the remainder of dividing 8.625 by 0.75:

```
var x = 8.625
print(x / 0.75)
// Prints "11.5"

let q = (x / 0.75).rounded(.toNearestOrEven)
// q == 12.0
x.formRemainder(dividingBy: 0.75)
// x == -0.375

let x1 = 0.75 * q + x
// x1 == 8.625
```

If this value and `other` are finite numbers, the remainder is in the
closed range `-abs(other / 2)...abs(other / 2)`. The
`formRemainder(dividingBy:)` method is always exact.

---

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