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# computeNormBackward(input:output:axes:outputGradient:generatingInputGradient:)

Backpropogates gradients for the compute norm function.

```
static func computeNormBackward(input: BNNSNDArrayDescriptor, output: BNNSNDArrayDescriptor, axes: [Int]? = nil, outputGradient: BNNSNDArrayDescriptor, generatingInputGradient inputGradient: BNNSNDArrayDescriptor) throws
```

## Parameters

`input`

The descriptor of the input.

`output`

The descriptor of the output.

`axes`

The indices of the axes over which the function computes the norm. Set to `nil` to specify that the function computes the norm over the entire tensor.

`outputGradient`

The descriptor of the output delta.

`inputGradient`

The descriptor of the input delta.

---

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