---
title: trajectoryLength
framework: vision
role: symbol
role_heading: Instance Property
path: vision/vndetecttrajectoriesrequest/trajectorylength
---

# trajectoryLength

The number of points to detect before calculating a trajectory.

## Declaration

```swift
var trajectoryLength: Int { get }
```

## See Also

### Configuring the Request

- [targetFrameTime](vision/vndetecttrajectoriesrequest/targetframetime.md)
- [objectMinimumNormalizedRadius](vision/vndetecttrajectoriesrequest/objectminimumnormalizedradius.md)
- [objectMaximumNormalizedRadius](vision/vndetecttrajectoriesrequest/objectmaximumnormalizedradius.md)
- [minimumObjectSize](vision/vndetecttrajectoriesrequest/minimumobjectsize.md)
- [maximumObjectSize](vision/vndetecttrajectoriesrequest/maximumobjectsize.md)