---
title: "acos(_:)"
framework: simd
role: symbol
role_heading: Function
path: "simd/acos(_:)-2blze"
---

# acos(_:)

Returns the arccosine of each element in a vector.

## Declaration

```swift
func acos(_ x: simd_float4) -> simd_float4
```

## See Also

### Trigonometric Functions

- [asin(_:)](simd/asin(_:)-87ban.md)
- [atan(_:)](simd/atan(_:)-8xa90.md)
- [atan2(_:_:)](simd/atan2(_:_:)-63ije.md)
- [cos(_:)](simd/cos(_:)-8qcj2.md)
- [cospi(_:)](simd/cospi(_:)-5chnf.md)
- [sin(_:)](simd/sin(_:)-80x4.md)
- [sinpi(_:)](simd/sinpi(_:)-71xz.md)
- [sincos(_:)](simd/sincos(_:)-8bfn1.md)
- [sincospi(_:)](simd/sincospi(_:)-84wzt.md)
- [tan(_:)](simd/tan(_:)-7uvy9.md)
- [tanpi(_:)](simd/tanpi(_:)-93eul.md)