> For the complete documentation index, see [llms.txt](https://docs.seldon.ai/alibi-explain/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.seldon.ai/alibi-explain/api-reference/explainers/similarity/metrics.md).

# alibi.explainers.similarity.metrics

## Functions

### `asym_dot`

```python
asym_dot(X: numpy.ndarray, Y: numpy.ndarray, eps: float = 1e-07) -> Union[float, numpy.ndarray]
```

Computes the influence of training instances `Y` to test instances `X`. This is an asymmetric kernel. (:math:`X^T Y/\|Y\|^2`). See the `paper <https://arxiv.org/abs/2102.05262>`\_ for more details. Each of `X` and `Y` should have a leading batch dimension of size at least 1.

| Name  | Type            | Default | Description          |
| ----- | --------------- | ------- | -------------------- |
| `X`   | `numpy.ndarray` |         | Matrix of vectors.   |
| `Y`   | `numpy.ndarray` |         | Matrix of vectors.   |
| `eps` | `float`         | `1e-07` | Numerical stability. |

**Returns**

* Type: `Union[float, numpy.ndarray]`

### `cos`

```python
cos(X: numpy.ndarray, Y: numpy.ndarray, eps: float = 1e-07) -> Union[float, numpy.ndarray]
```

Computes the cosine between the vector(s) in X and vector Y. (:math:`X^T Y/\|X\|\|Y\|`). Each of `X` and `Y` should have a leading batch dimension of size at least 1.

| Name  | Type            | Default | Description          |
| ----- | --------------- | ------- | -------------------- |
| `X`   | `numpy.ndarray` |         | Matrix of vectors.   |
| `Y`   | `numpy.ndarray` |         | Matrix of vectors.   |
| `eps` | `float`         | `1e-07` | Numerical stability. |

**Returns**

* Type: `Union[float, numpy.ndarray]`

### `dot`

```python
dot(X: numpy.ndarray, Y: numpy.ndarray) -> Union[float, numpy.ndarray]
```

Performs a dot product between the vector(s) in X and vector Y. (:math:`X^T Y = \sum_i X_i Y_i`). Each of `X` and `Y` should have a leading batch dimension of size at least 1.

| Name | Type            | Default | Description        |
| ---- | --------------- | ------- | ------------------ |
| `X`  | `numpy.ndarray` |         | Matrix of vectors. |
| `Y`  | `numpy.ndarray` |         | Matrix of vectors. |

**Returns**

* Type: `Union[float, numpy.ndarray]`