---
title: "init(lowHalf:highHalf:)"
framework: swift
role: symbol
role_heading: Initializer
path: "swift/simd4/init(lowhalf:highhalf:)-5ye5o"
---

# init(lowHalf:highHalf:)

A vector formed by concatenating lowHalf and highHalf.

## Declaration

```swift
init(lowHalf: SIMD2<UInt64>, highHalf: SIMD2<UInt64>)
```

## Discussion

Discussion Equivalent to: var result = SIMD4<UInt64>() for i in 0..<2 {   result[i] = lowHalf[i]   result[2+i] = highHalf[i] }