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# init(_:duration:spring:startVelocity:)

Creates a new keyframe using the given value and timestamp.

```
init(_ to: Value, duration: TimeInterval? = nil, spring: Spring = Spring(), startVelocity: Value? = nil)
```

## Parameters

`to`

The value of the keyframe.

`duration`

The duration of the segment defined by this keyframe,
or nil to use the settling duration of the spring.

`spring`

The spring that defines the shape of the segment befire
this keyframe

`startVelocity`

The velocity of the value at the start of the
segment, or `nil` to automatically compute the velocity to maintain
smooth motion.

---

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