---
title: "mutatingSlice(at:)"
framework: coreai
role: symbol
role_heading: Instance Method
path: "coreai/ndarray/mutableview/mutatingslice(at:)-9pmi4"
---

# mutatingSlice(at:)

Returns a sub-view with the same rank as this view by slicing the dimensions at the provided ranges.

## Declaration

```swift
@export(implementation) mutating func mutatingSlice(at ranges: [any NDArray.RangeExpression]) -> NDArray.MutableView<Element>
```

## Parameters

- `ranges`: The range expressions describing where to slice along each dimension. ranges.count must be ≤ rank. Unspecified trailing dimensions are assumed to be .all.

## Discussion

Discussion For example if you have a 3D NDArray and want to increment a specific region, you can slice that region and then access a span over it (or use withUnsafeMutablePointer if not contiguous). /// Updates the desired channel and range of rows func incrementRegion(   of mutableView: inout NDArray.MutableView<Float>,   channel: Int,   startRow: Int,   endRow: Int ) {   var region = mutableView.mutatingSlice(at: [channel, startRow..<endRow, .all])   var mutableSpan = region.contiguousElements! // contiguous region expected in this case

for i in mutableSpan.indices {     mutableSpan[i] += 1   } }