---
title: tensionValues
framework: quartzcore
role: symbol
role_heading: Instance Property
path: quartzcore/cakeyframeanimation/tensionvalues
---

# tensionValues

An array of numbers that define the tightness of the curve.

## Declaration

```swift
var tensionValues: [NSNumber]? { get set }
```

## Discussion

Discussion This property is an array of NSNumber objects, used only for the cubic calculation modes. Positive values indicate a tighter curve while negative values indicate a rounder curve. The first value defines the behavior of the tangent to the first control point, the second value controls the second point’s tangents, and so on. If you do not specify a value for a given control point, the value 0 is used.

## See Also

### Cubic Mode Attributes

- [continuityValues](quartzcore/cakeyframeanimation/continuityvalues.md)
- [biasValues](quartzcore/cakeyframeanimation/biasvalues.md)