# pgRouting Manual (3.6)

## Driving Distance - Category

- pgr_drivingDistance - Driving Distance based on Dijkstra’s algorithm

- pgr_primDD - Driving Distance based on Prim’s algorithm

- pgr_kruskalDD - Driving Distance based on Kruskal’s algorithm

- Post pocessing

  - pgr_alphaShape - Alpha shape computation

Proposed

Warning

Proposed functions for next mayor release.

- They are not officially in the current release.

- They will likely officially be part of the next mayor release:

  - The functions make use of ANY-INTEGER and ANY-NUMERICAL

  - Name might not change. (But still can)

  - Signature might not change. (But still can)

  - Functionality might not change. (But still can)

  - pgTap tests have being done. But might need more.

  - Documentation might need refinement.

- pgr_withPointsDD - Proposed - Driving Distance based on pgr_withPoints

Calculate nodes that are within a distance.

- Extracts all the nodes that have costs less than or equal to the value distance.

- The edges extracted will conform to the corresponding spanning tree.

- Edge \((u, v)\) will not be included when:

  - The distance from the root to \(u\) > limit distance.

  - The distance from the root to \(v\) > limit distance.

  - No new nodes are created on the graph, so when is within the limit and is not within the limit, the edge is not included.

## Parameters

Parameter | Type | Description
--- | --- | ---
Edges SQL | `TEXT` | Edges SQL as described below.
Root vid | `BIGINT` | Identifier of the root vertex of the tree.

Root vids

`ARRAY[ANY-INTEGER]`

Array of identifiers of the root vertices.

- \(0\) values are ignored

- For optimization purposes, any duplicated value is ignored.

distance | `FLOAT` | Upper limit for the inclusion of a node in the result.

Where:

ANY-INTEGER:

  `SMALLINT`, `INTEGER`, `BIGINT`

ANY-NUMERIC:

  `SMALLINT`, `INTEGER`, `BIGINT`, `REAL`, `FLOAT`

## Inner Queries

### Edges SQL

Column | Type | Default | Description
--- | --- | --- | ---
`id` | ANY-INTEGER |  | Identifier of the edge.
`source` | ANY-INTEGER |  | Identifier of the first end point vertex of the edge.
`target` | ANY-INTEGER |  | Identifier of the second end point vertex of the edge.
`cost` | ANY-NUMERICAL |  | Weight of the edge (`source`, `target`)

`reverse_cost`

ANY-NUMERICAL

-1

Weight of the edge (`target`, `source`)

- When negative: edge (`target`, `source`) does not exist, therefore it’s not part of the graph.

Where:

ANY-INTEGER:

  `SMALLINT`, `INTEGER`, `BIGINT`

ANY-NUMERICAL:

  `SMALLINT`, `INTEGER`, `BIGINT`, `REAL`, `FLOAT`

### Result columns

Returns set of `(seq, depth, start_vid, pred, node, edge, cost, agg_cost)`

Parameter | Type | Description
--- | --- | ---
`seq` | `BIGINT` | Sequential value starting from \(1\).

`depth`

`BIGINT`

Depth of the `node`.

- \(0\) when `node` = `start_vid`.

- \(depth-1\) is the depth of `pred`

`start_vid` | `BIGINT` | Identifier of the root vertex.

`pred`

`BIGINT`

Predecessor of `node`.

- When `node` = `start_vid` then has the value `node`.

`node` | `BIGINT` | Identifier of `node` reached using `edge`.

`edge`

`BIGINT`

Identifier of the `edge` used to arrive from `pred` to `node`.

- \(-1\) when `node` = `start_vid`.

`cost` | `FLOAT` | Cost to traverse `edge`.
`agg_cost` | `FLOAT` | Aggregate cost from `start_vid` to `node`.

Where:

ANY-INTEGER:

  SMALLINT, INTEGER, BIGINT

ANY-NUMERIC:

  SMALLINT, INTEGER, BIGINT, REAL, FLOAT, NUMERIC

Note

Column `pred` only applies to pgr_drivingDistance and pgr_withPointsDD - Proposed.

## See Also

Indices and tables

- Index

- Search Page