---
sidebar:
  hidden: true
title: roboto.analytics.signal_similarity.match
---
## Module Contents

### Match

```python
class roboto.analytics.signal_similarity.match.Match
```

`from roboto.analytics import Match`

[Source](https://github.com/roboto-ai/roboto-python-sdk/blob/main/src/roboto/analytics/signal_similarity/match.py#L96-L185)

A subsequence of a target signal that is similar to a query signal.

**Attributes**

- **Match.context** (`MatchContext`): Correlate a matched subsequence back to its source.

- **Match.distance** (`float`): Measure of similarity between a query signal and the subsequence of the target signal this Match represents. A smaller distance indicates a closer match.

  In single-scale search (`scale=None`) this is the raw z-normalised Euclidean distance produced by MASS, with range `[0, 2·√N]` where `N` is the query length.

  In multi-scale search (`scale` provided) this is multiplied by `√N / √M` (where `N` is the original needle length and `M` is the resampled length at that scale step), projecting onto the same `[0, 2·√N]` range as single-scale search. This means a `max_distance` threshold calibrated on single-scale search transfers directly to multi-scale search without adjustment.

- **Match.end_idx** (`int`): The end index in the target signal of this match.

- **Match.end_time** (`pandas.Timestamp`): The end time in the target signal of this match.

- **Match.scale** (`float`) = `1.0`: The time-scale factor at which this match was found.

  A value of `1.0` means the matched subsequence has the same length as the query. Values greater than `1.0` mean the matched subsequence is proportionally longer (the action occurred more slowly in the target than in the query). Values less than `1.0` mean the matched subsequence is proportionally shorter (the action occurred more quickly).

  This field is only meaningful when `scale` is passed to [`find_similar_signals()`](/reference/python-sdk/roboto/analytics/signal_similarity/signal_similarity#roboto.analytics.signal_similarity.signal_similarity.find_similar_signals).

- **Match.start_idx** (`int`): The start index in the target signal of this match.

- **Match.start_time** (`pandas.Timestamp`): The start time in the target signal of this match.

- **Match.subsequence** (`pandas.DataFrame`): The subsequence of the target signal this Match represents. It is equivalent to `target[start_idx:end_idx]`.

#### Match.to_event()

```python
def to_event(
    name: str = 'Signal Similarity Match Result',
    caller_org_id: Optional[str] = None,
    roboto_client: Optional[roboto.http.RobotoClient] = None,
) -> roboto.domain.events.Event
```

[Source](https://github.com/roboto-ai/roboto-python-sdk/blob/main/src/roboto/analytics/signal_similarity/match.py#L161-L185)

Create a Roboto Platform event out of this similarity match result.

**Parameters**

- **name** (`str`)
- **caller_org_id** (`Optional[str]`)
- **roboto_client** (`Optional[roboto.http.RobotoClient]`)

**Returns**

- `roboto.domain.events.Event`

### MatchContext

```python
class roboto.analytics.signal_similarity.match.MatchContext
```

`from roboto.analytics import MatchContext`

[Source](https://github.com/roboto-ai/roboto-python-sdk/blob/main/src/roboto/analytics/signal_similarity/match.py#L82-L92)

Correlate a matched subsequence back to its source.

**Attributes**

- **MatchContext.dataset_id** (`str | None`) = `None`
- **MatchContext.file_id** (`str | None`) = `None`
- **MatchContext.message_paths** (`collections.abc.Sequence[str]`)
- **MatchContext.topic_id** (`str`)
- **MatchContext.topic_name** (`str`)

### Scale

```python
class roboto.analytics.signal_similarity.match.Scale
```

`from roboto.analytics import Scale`

[Source](https://github.com/roboto-ai/roboto-python-sdk/blob/main/src/roboto/analytics/signal_similarity/match.py#L22-L78)

Configuration for rate-invariant (multi-scale) signal similarity search.

Searching across multiple scales finds a query pattern regardless of how quickly or slowly it unfolds in the target. For example, a robot lifting a cup in 1 second and the same robot lifting a cup in 3 seconds would both be found.

`min` and `max` are positive scale factors relative to the original query length. A scale of `1.0` corresponds to the original query length; `2.0` searches for target subsequences twice as long (action happened at half speed); `0.5` searches for subsequences half as long (action happened at double speed).

While `Scale.any()` provides a convenient wide-range preset, providing domain-informed bounds (e.g. `Scale(min=0.5, max=3.0)` for a motion that can happen between half and triple speed) will both improve match quality — by concentrating the search grid where matches are physically plausible — and reduce compute by avoiding unnecessary scale steps.

**Attributes**

- **Scale.max** (`float`): Maximum scale factor (must be >= `min`).

- **Scale.min** (`float`): Minimum scale factor (must be positive).

- **Scale.spacing** (`Literal['log', 'linear']`) = `'log'`: How to distribute scale values across the range.

  - `"log"` (default) — geometrically spaced; equal ratio between adjacent steps, which is more natural for speed ratios (e.g. 0.5x, 1x, 2x are equally spaced on a log scale).
  - `"linear"` — linearly spaced.

- **Scale.steps** (`int`) = `10`: Number of scale values to sample across the range.

#### Scale.any()

```python
@classmethod
def any() -> Scale
```

[Source](https://github.com/roboto-ai/roboto-python-sdk/blob/main/src/roboto/analytics/signal_similarity/match.py#L69-L71)

Well-known preset covering a wide range of speed ratios (0.1x to 10x).

**Returns**

- `Scale`

#### Scale.factors()

```python
def factors() -> list[float]
```

[Source](https://github.com/roboto-ai/roboto-python-sdk/blob/main/src/roboto/analytics/signal_similarity/match.py#L73-L78)

Return a list of scale factors spanning the configured range.

**Returns**

- `list[float]`