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# MLCGramMatrixLayer

A layer that computes the uncentered cross-correlation values between the spacial planes of each feature channel of a tensor.

```
class MLCGramMatrixLayer
```

## Overview

For example, if the input tensor batch function is:

`x = x[b, y, x, c]`

The computation performed by this layer is:

`y = y[b, 1, f, c] = alpha * sum_{x, y} x[b, y, x, f] * x[b, y, x, c]`

Interpret this operation as computing all combinations of fully connected layers between the different spatial planes of the input tensor.

The layer performs this operation independently for each tensor in a batch. Then the layer stores these results in the feature channel and x-coordinate indices of the output batch.

Legend:

- `b`: The batch index.
- `y` and `x`: The spatial coordinates.
- `c`: The feature channel index.
- `alpha`: The scaling factor.

## Topics

### Creating Gram Matrix Layers

[`init(scale:)`](/documentation/MLCompute/MLCGramMatrixLayer/init(scale:))

Creates a gram matrix layer with the scaling factor you specify.

### Inspecting Gram Matrix Layers

[`scale`](/documentation/MLCompute/MLCGramMatrixLayer/scale)

The scaling factor.


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