# Map Match

## Match GPS coordinates to the road network

`map_match.match(**kwargs) -> MapMatchResult`

**post** `/api/v1/map-match`

Match GPS coordinates to the road network

### Parameters

- `coordinates: Array[{ lat, lng}]`

  GPS coordinates to match, in order of travel (max 50 points)

  - `lat: Float`

    Latitude in decimal degrees (-90 to 90)

  - `lng: Float`

    Longitude in decimal degrees (-180 to 180)

- `radiuses: Array[Float]`

  Search radius per coordinate in meters. Must have the same length as `coordinates` or be omitted entirely. Default: 50m per point.

### Returns

- `class MapMatchResult`

  Map matching result as a GeoJSON FeatureCollection. Each Feature is a snapped tracepoint. The top-level `matchings` array contains the matched sub-routes connecting consecutive tracepoints.

  - `features: Array[{ geometry, properties, type}]`

    Snapped tracepoint Features in input order

    - `geometry: GeoJsonGeometry`

      GeoJSON Geometry object per RFC 7946. Coordinates use [longitude, latitude] order. 3D coordinates [lng, lat, elevation] are used for elevation endpoints.

      - `coordinates: Array[Float] | Array[Array[Float]] | Array[Array[Array[Float]]] | Array[Array[Array[Array[Float]]]]`

        Coordinates array. Nesting depth varies by geometry type: Point = [lng, lat], LineString = [[lng, lat], ...], Polygon = [[[lng, lat], ...], ...], etc.

        - `Array[Float]`

          [longitude, latitude] or [longitude, latitude, elevation]

        - `Array[Array[Float]]`

          Array of [lng, lat] positions

        - `Array[Array[Array[Float]]]`

          Array of linear rings / line strings

        - `Array[Array[Array[Array[Float]]]]`

          Array of polygons

      - `type: :Point | :LineString | :Polygon | 3 more`

        Geometry type

        - `:Point`

        - `:LineString`

        - `:Polygon`

        - `:MultiPoint`

        - `:MultiLineString`

        - `:MultiPolygon`

    - `properties: { distance_m, edge_id, matchings_index, 3 more}`

      - `distance_m: Float`

        Distance from the original GPS point to the snapped point in meters

      - `edge_id: Integer`

        Road edge ID the point was snapped to

      - `matchings_index: Integer`

        Index into the `matchings` array indicating which matching sub-route this point belongs to

      - `name: String`

        Road name at the snapped point

      - `original: Array[Float]`

        Original GPS coordinate as [lng, lat]

      - `waypoint_index: Integer`

        Index of this tracepoint in the original `coordinates` array

    - `type: :Feature`

      - `:Feature`

  - `matchings: Array[Hash[Symbol, untyped]]`

    Matched sub-routes. Each matching connects a contiguous sequence of tracepoints that could be matched to roads.

  - `type: :FeatureCollection`

    - `:FeatureCollection`

### Example

```ruby
require "plaza"

plaza = Plaza::Client.new(
  api_key: "My API Key",
  environment: "local" # defaults to "production"
)

map_match_result = plaza.map_match.match(
  coordinates: [{lat: 48.8566, lng: 2.3522}, {lat: 48.857, lng: 2.353}, {lat: 48.8575, lng: 2.354}]
)

puts(map_match_result)
```

#### Response

```json
{
  "features": [
    {
      "geometry": {
        "coordinates": [
          2.3522,
          48.8566
        ],
        "type": "Point"
      },
      "properties": {
        "distance_m": 0,
        "edge_id": 0,
        "matchings_index": 0,
        "name": "name",
        "original": [
          0,
          0
        ],
        "waypoint_index": 0
      },
      "type": "Feature"
    }
  ],
  "matchings": [
    {
      "foo": "bar"
    }
  ],
  "type": "FeatureCollection"
}
```

## Domain Types

### Map Match Request

- `class MapMatchRequest`

  GPS trace to snap to the road network. Provide an array of coordinate objects representing the GPS points. Maximum 50 points per request.

  - `coordinates: Array[{ lat, lng}]`

    GPS coordinates to match, in order of travel (max 50 points)

    - `lat: Float`

      Latitude in decimal degrees (-90 to 90)

    - `lng: Float`

      Longitude in decimal degrees (-180 to 180)

  - `radiuses: Array[Float]`

    Search radius per coordinate in meters. Must have the same length as `coordinates` or be omitted entirely. Default: 50m per point.

### Map Match Result

- `class MapMatchResult`

  Map matching result as a GeoJSON FeatureCollection. Each Feature is a snapped tracepoint. The top-level `matchings` array contains the matched sub-routes connecting consecutive tracepoints.

  - `features: Array[{ geometry, properties, type}]`

    Snapped tracepoint Features in input order

    - `geometry: GeoJsonGeometry`

      GeoJSON Geometry object per RFC 7946. Coordinates use [longitude, latitude] order. 3D coordinates [lng, lat, elevation] are used for elevation endpoints.

      - `coordinates: Array[Float] | Array[Array[Float]] | Array[Array[Array[Float]]] | Array[Array[Array[Array[Float]]]]`

        Coordinates array. Nesting depth varies by geometry type: Point = [lng, lat], LineString = [[lng, lat], ...], Polygon = [[[lng, lat], ...], ...], etc.

        - `Array[Float]`

          [longitude, latitude] or [longitude, latitude, elevation]

        - `Array[Array[Float]]`

          Array of [lng, lat] positions

        - `Array[Array[Array[Float]]]`

          Array of linear rings / line strings

        - `Array[Array[Array[Array[Float]]]]`

          Array of polygons

      - `type: :Point | :LineString | :Polygon | 3 more`

        Geometry type

        - `:Point`

        - `:LineString`

        - `:Polygon`

        - `:MultiPoint`

        - `:MultiLineString`

        - `:MultiPolygon`

    - `properties: { distance_m, edge_id, matchings_index, 3 more}`

      - `distance_m: Float`

        Distance from the original GPS point to the snapped point in meters

      - `edge_id: Integer`

        Road edge ID the point was snapped to

      - `matchings_index: Integer`

        Index into the `matchings` array indicating which matching sub-route this point belongs to

      - `name: String`

        Road name at the snapped point

      - `original: Array[Float]`

        Original GPS coordinate as [lng, lat]

      - `waypoint_index: Integer`

        Index of this tracepoint in the original `coordinates` array

    - `type: :Feature`

      - `:Feature`

  - `matchings: Array[Hash[Symbol, untyped]]`

    Matched sub-routes. Each matching connects a contiguous sequence of tracepoints that could be matched to roads.

  - `type: :FeatureCollection`

    - `:FeatureCollection`