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Network analysis

Service area (from layer)

Returns all the edges or parts of edges of a network that can be reached within a distance or a time, starting from a point layer. This allows evaluation of accessibility within a network, eg what are the places I can navigate to on a road network without spending cost greater than a given value (the cost can be distance or time).

Parameters

Vector layer representing the network [vector: line]
Line vector layer representing the network to be covered.
Vector layer with start points [vector: point]
Point vector layer whose features are used as start points to generate the service areas.
Path type to calculate [enumeration]

The type of path to calculate.

Options are:

  • 0 — Shortest
  • 1 — Fastest

Default: 0

Travel cost [number]

The value is estimated as a distance (in the network layer units) when looking for the Shortest path and as time (in seconds) for the Fastest path.

Default: 0.0

Advanced parameters
Direction field [tablefield: string]

Optional

The field used to specify directions for the network edges.

The values used in this field are specified with the three parameters Value for forward direction, Value for backward direction and Value for both directions. Forward and reverse directions correspond to a one-way edge, “both directions” indicates a two-way edge.

If a feature does not have a value in this field, or no field is set then the default direction setting (provided with the Default direction parameter) is used.

Value for forward direction [string]

Optional

Value set in the direction field to identify edges with a forward direction.

Value for backward direction [string]

Optional

Value set in the direction field to identify edges with a backward direction.

Value for both directions [string]

Optional

Value set in the direction field to identify bidirectional edges.

Default direction [enumeration]

If a feature has no value set in the direction field or if no direction field is set, then this direction value is used.

Available options are:

  • 0 — Forward direction
  • 1 — Backward direction
  • 2 — Both directions

Default: 2

Speed field [tablefield: string]

Optional

Field providing the speed value (in km/h) for the edges of the network when looking for the fastest path.

If a feature does not have a value in this field, or no field is set then the default speed value (provided with the Default speed parameter) is used.

Default speed (km/h) [number]

Value to use to calculate the travel time if no speed field is provided for an edge.

Default: 50.0

Topology tolerance [number]

Two lines with nodes closer than the specified tolerance are considered connected.

Default: 0.0

Include upper/lower bound points [boolean]

Creates a point layer output with two points for each edge at the boundaries of the service area. One point is the start of that edge, the other is the end.

Default: False

Outputs

Service area (lines) [vector: line]
Line layer representing the parts of the network that can be serviced by the start points.
Service area (boundary nodes) [vector: point]
Point layer representing the furthest points on the network from the start points, for the given cost.

Service area (from point)

Returns all the edges or parts of edges of a network that can be reached within a given distance or time, starting from a point feature. This allows the evaluation of accessibility within a network, eg what are the places I can navigate to on a road network without spending a cost greater than a given value (the cost can be distance or time).

Parameters

Vector layer representing the network [vector: line]
Line vector layer representing the network to be covered.
Start point (x, y) [coordinates]
Coordinate of the point to calculate the service area around.
Path type to calculate [enumeration]

The type of path to calculate.

Options are:

  • 0 — Shortest
  • 1 — Fastest

Default: 0

Travel cost [number]

The value is estimated as a distance (in the network layer units) when looking for the Shortest path and as time (in seconds) for the Fastest path.

Default: 0.0

Advanced parameters
Direction field [tablefield: string]

Optional

The field used to specify directions for the network edges.

The values used in this field are specified with the three parameters Value for forward direction, Value for backward direction and Value for both directions. Forward and reverse directions correspond to a one-way edge, “both directions” indicates a two-way edge.

If a feature does not have a value in this field, or no field is set then the default direction setting (provided with the Default direction parameter) is used.

Value for forward direction [string]

Optional

Value set in the direction field to identify edges with a forward direction.

Value for backward direction [string]

Optional

Value set in the direction field to identify edges with a backward direction.

Value for both directions [string]

Optional

Value set in the direction field to identify bidirectional edges.

Default direction [enumeration]

If a feature has no value set in the direction field or if no direction field is set, then this direction value is used.

Available options are:

  • 0 — Forward direction
  • 1 — Backward direction
  • 2 — Both directions

Default: 2

Speed field [tablefield: string]

Optional

Field providing the speed value (in km/h) for the edges of the network when looking for the fastest path.

If a feature does not have a value in this field, or no field is set then the default speed value (provided with the Default speed parameter) is used.

Default speed (km/h) [number]

Value to use to calculate the travel time if no speed field is provided for an edge.

Default: 50.0

Topology tolerance [number]

Two lines with nodes closer than the specified tolerance are considered connected.

Default: 0.0

Include upper/lower bound points [boolean]

Creates a point layer output with two points for each edge at the boundaries of the service area. One point is the start of that edge, the other is the end.

Default: False

Outputs

Service area (lines) [vector: line]
Line layer representing the parts of the network that can be serviced by the start point.
Service area (boundary nodes) [vector: point]
Point layer representing the furthest points on the network from the start point, for the given cost.

Shortest path (layer to point)

Computes the optimal (shortest or fastest) routes from multiple start points defined by a vector layer and a given end point.

Parameters

Vector layer representing the network [vector: line]
Line vector layer representing the network to be covered.
Path type to calculate [enumeration]

The type of path to calculate.

Options are:

  • 0 — Shortest
  • 1 — Fastest

Default: 0

Vector layer with start points [vector: point]
Point vector layer whose features are used as start points of the routes.
End point (x, y) [coordinates]
Point feature representing the end point of the routes.
Advanced parameters
Direction field [tablefield: string]

Optional

The field used to specify directions for the network edges.

The values used in this field are specified with the three parameters Value for forward direction, Value for backward direction and Value for both directions. Forward and reverse directions correspond to a one-way edge, “both directions” indicates a two-way edge.

If a feature does not have a value in this field, or no field is set then the default direction setting (provided with the Default direction parameter) is used.

Value for forward direction [string]

Optional

Value set in the direction field to identify edges with a forward direction.

Value for backward direction [string]

Optional

Value set in the direction field to identify edges with a backward direction.

Value for both directions [string]

Optional

Value set in the direction field to identify bidirectional edges.

Default direction [enumeration]

If a feature has no value set in the direction field or if no direction field is set, then this direction value is used.

Available options are:

  • 0 — Forward direction
  • 1 — Backward direction
  • 2 — Both directions

Default: 2

Speed field [tablefield: string]

Optional

Field providing the speed value (in km/h) for the edges of the network when looking for the fastest path.

If a feature does not have a value in this field, or no field is set then the default speed value (provided with the Default speed parameter) is used.

Default speed (km/h) [number]

Value to use to calculate the travel time if no speed field is provided for an edge.

Default: 50.0

Topology tolerance [number]

Two lines with nodes closer than the specified tolerance are considered connected.

Default: 0.0

Outputs

Shortest path [vector: line]
Line layer of the shortest or fastest path from each of the start points to the end point.

Shortest path (point to layer)

Computes the optimal (shortest or fastest) routes between a given start point and multiple end points defined by a point vector layer.

Parameters

Vector layer representing the network [vector: line]
Line vector layer representing the network to be covered.
Path type to calculate [enumeration]

The type of path to calculate.

Options are:

  • 0 — Shortest
  • 1 — Fastest

Default: 0

Start point (x, y) [coordinates]
Point feature representing the start point of the routes.
Vector layer with end points [vector: point]
Point vector layer whose features are used as end points of the routes.
Advanced parameters
Direction field [tablefield: string]

Optional

The field used to specify directions for the network edges.

The values used in this field are specified with the three parameters Value for forward direction, Value for backward direction and Value for both directions. Forward and reverse directions correspond to a one-way edge, “both directions” indicates a two-way edge.

If a feature does not have a value in this field, or no field is set then the default direction setting (provided with the Default direction parameter) is used.

Value for forward direction [string]

Optional

Value set in the direction field to identify edges with a forward direction.

Value for backward direction [string]

Optional

Value set in the direction field to identify edges with a backward direction.

Value for both directions [string]

Optional

Value set in the direction field to identify bidirectional edges.

Default direction [enumeration]

If a feature has no value set in the direction field or if no direction field is set, then this direction value is used.

Available options are:

  • 0 — Forward direction
  • 1 — Backward direction
  • 2 — Both directions

Default: 2

Speed field [tablefield: string]

Optional

Field providing the speed value (in km/h) for the edges of the network when looking for the fastest path.

If a feature does not have a value in this field, or no field is set then the default speed value (provided with the Default speed parameter) is used.

Default speed (km/h) [number]

Value to use to calculate the travel time if no speed field is provided for an edge.

Default: 50.0

Topology tolerance [number]

Two lines with nodes closer than the specified tolerance are considered connected.

Default: 0.0

Outputs

Shortest path [vector: line]
Line layer of the shortest or fastest path from the start point to each of the end points.

Shortest path (point to point)

Computes the optimal (shortest or fastest) route between a given start point and a given end point.

Parameters

Vector layer representing the network [vector: line]
Line vector layer representing the network to be covered.
Path type to calculate [enumeration]

The type of path to calculate.

Options are:

  • 0 — Shortest
  • 1 — Fastest

Default: 0

Start point (x, y) [coordinates]
Point feature representing the start point of the route.
End point (x, y) [coordinates]
Point feature representing the end point of the route.
Advanced parameters
Direction field [tablefield: string]

Optional

The field used to specify directions for the network edges.

The values used in this field are specified with the three parameters Value for forward direction, Value for backward direction and Value for both directions. Forward and reverse directions correspond to a one-way edge, “both directions” indicates a two-way edge.

If a feature does not have a value in this field, or no field is set then the default direction setting (provided with the Default direction parameter) is used.

Value for forward direction [string]

Optional

Value set in the direction field to identify edges with a forward direction.

Value for backward direction [string]

Optional

Value set in the direction field to identify edges with a backward direction.

Value for both directions [string]

Optional

Value set in the direction field to identify bidirectional edges.

Default direction [enumeration]

If a feature has no value set in the direction field or if no direction field is set, then this direction value is used.

Available options are:

  • 0 — Forward direction
  • 1 — Backward direction
  • 2 — Both directions

Default: 2

Speed field [tablefield: string]

Optional

Field providing the speed value (in km/h) for the edges of the network when looking for the fastest path.

If a feature does not have a value in this field, or no field is set then the default speed value (provided with the Default speed parameter) is used.

Default speed (km/h) [number]

Value to use to calculate the travel time if no speed field is provided for an edge.

Default: 50.0

Topology tolerance [number]

Two lines with nodes closer than the specified tolerance are considered connected.

Default: 0.0

Outputs

Shortest path [vector: line]
Line layer of the shortest or fastest path from the start point to the end point.