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# BNNS.DataLayout

Constants that describe the data layout of an n-dimensional array descriptor shape.

```
enum DataLayout
```

## Topics

### Data Layout Constants

[`case vector`](/documentation/Accelerate/BNNS/DataLayout/vector)

A constant that represents a 1D vector.

[`case matrixColumnMajor`](/documentation/Accelerate/BNNS/DataLayout/matrixColumnMajor)

A constant that represents a 2D column-major matrix.

[`case matrixRowMajor`](/documentation/Accelerate/BNNS/DataLayout/matrixRowMajor)

A constant that represents a 2D row-major matrix.

[`case matrixFirstMajor`](/documentation/Accelerate/BNNS/DataLayout/matrixFirstMajor)

A constant that represents a 2D first-major matrix.

[`case matrixLastMajor`](/documentation/Accelerate/BNNS/DataLayout/matrixLastMajor)

A constant that represents a 2D last-major matrix.

[`case imageCHW`](/documentation/Accelerate/BNNS/DataLayout/imageCHW)

A constant that represents a 3D image stack.

[`case tensor3DFirstMajor`](/documentation/Accelerate/BNNS/DataLayout/tensor3DFirstMajor)

A constant that represents a 3D first-major tensor.

[`case tensor3DLastMajor`](/documentation/Accelerate/BNNS/DataLayout/tensor3DLastMajor)

A constant that represents a 3D last-major tensor.

[`case tensor3DNSE`](/documentation/Accelerate/BNNS/DataLayout/tensor3DNSE)

A constant that represents a 3D tensor with size ordered by embedding dimension, sequence length, batch size.

[`case tensor3DSNE`](/documentation/Accelerate/BNNS/DataLayout/tensor3DSNE)

A constant that represents a 3D tensor with size ordered by embedding dimension, batch size, sequence length.

[`case convolutionWeightsOIHW`](/documentation/Accelerate/BNNS/DataLayout/convolutionWeightsOIHW)

A constant that represents a 4D array of convolution weights.

[`case tensor4DFirstMajor`](/documentation/Accelerate/BNNS/DataLayout/tensor4DFirstMajor)

A constant that represents a 4D first-major tensor.

[`case tensor4DLastMajor`](/documentation/Accelerate/BNNS/DataLayout/tensor4DLastMajor)

A constant that represents a 4D last-major tensor.

[`case tensor5DFirstMajor`](/documentation/Accelerate/BNNS/DataLayout/tensor5DFirstMajor)

A constant that represents a 5D first-major tensor.

[`case tensor5DLastMajor`](/documentation/Accelerate/BNNS/DataLayout/tensor5DLastMajor)

A constant that represents a 5D last-major tensor.

[`case tensor6DFirstMajor`](/documentation/Accelerate/BNNS/DataLayout/tensor6DFirstMajor)

A constant that represents a 6D first-major tensor.

[`case tensor6DLastMajor`](/documentation/Accelerate/BNNS/DataLayout/tensor6DLastMajor)

A constant that represents a 6D last-major tensor.

[`case tensor7DFirstMajor`](/documentation/Accelerate/BNNS/DataLayout/tensor7DFirstMajor)

A constant that represents a 7D first-major tensor.

[`case tensor7DLastMajor`](/documentation/Accelerate/BNNS/DataLayout/tensor7DLastMajor)

A constant that represents a 7D last-major tensor.

[`case tensor8DFirstMajor`](/documentation/Accelerate/BNNS/DataLayout/tensor8DFirstMajor)

A constant that represents a 8D first-major tensor.

[`case tensor8DLastMajor`](/documentation/Accelerate/BNNS/DataLayout/tensor8DLastMajor)

A constant that represents a 8D last-major tensor.

### Determining the Number of Dimensions

[`var rank: Int`](/documentation/Accelerate/BNNS/DataLayout/rank)

The number of dimensions of the data layout.

## Relationships

### Conforms To

[`Equatable`](/documentation/Swift/Equatable)

[`Hashable`](/documentation/Swift/Hashable)

[`CaseIterable`](/documentation/Swift/CaseIterable)

---

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