.. only:: html
Network analysis
================
.. only:: html
.. contents::
:local:
:depth: 1
.. _qgisserviceareafromlayer:
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
..........
.. list-table::
:header-rows: 1
:widths: 20 20 20 40
:stub-columns: 0
* - Label
- Name
- Type
- Description
* - **Vector layer representing network**
- ``INPUT``
- [vector: line]
- Line vector layer representing the network to be covered
* - **Vector layer with start points**
- ``START_POINTS``
- [vector: point]
- Point vector layer whose features are used as start points
to generate the service areas
* - **Path type to calculate**
- ``STRATEGY``
- [enumeration]
Default: 0
- The type of path to calculate. One of:
* 0 --- Shortest
* 1 --- Fastest
* - **Travel cost (distance for "Shortest", time for "Fastest"**
- ``TRAVEL_COST``
- [number]
Default: 0
- 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.
* - **Direction field**
Optional
- ``DIRECTION_FIELD``
- [tablefield: string]
Default: None
- 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**
Optional
- ``VALUE_FORWARD``
- [string]
Default: '' (empty string)
- Value set in the direction field to identify edges with a
forward direction
* - **Value for backward direction**
Optional
- ``VALUE_BACKWARD``
- [string]
Default: '' (empty string)
- Value set in the direction field to identify edges with a
backward direction
* - **Value for both directions**
Optional
- ``VALUE_BOTH``
- [string]
Default: '' (empty string)
- Value set in the direction field to identify
bidirectional edges
* - **Default direction**
Optional
- ``DEFAULT_DIRECTION``
- [enumeration]
Default: 2
- If a feature has no value set in the direction field or
if no direction field is set, then this direction value
is used. One of:
* 0 --- Forward direction
* 1 --- Backward direction
* 2 --- Both directions
* - **Speed field**
Optional
- ``SPEED_FIELD``
- [tablefield: string]
Default: None
- 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)**
Optional
- ``DEFAULT_SPEED``
- [number]
Default: 50
- Value to use to calculate the travel time if no speed
field is provided for an edge
* - **Topology tolerance**
Optional
- ``TOLERANCE``
- [number]
Default: 0
- Two lines with nodes closer than the specified
tolerance are considered connected
* - **Include upper/lower bound points**
- ``INCLUDE_BOUNDS``
- [boolean]
Default: False
- 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.
* - **Service area (lines)**
- ``OUTPUT_LINES``
- [vector: line]
Default: ``[Create temporary layer]``
- Specify the output line layer for the service area.
One of:
* Skip output
* Create Temporary Layer (``TEMPORARY_OUTPUT``)
* Save to File...
* Save to Geopackage...
* Save to PostGIS Table
The file encoding can also be changed here.
* - **Service area (boundary nodes)**
- ``OUTPUT``
- [vector: point]
Default: ``[Skip output]``
- Specify the output point layer for the service area
boundary nodes. One of:
* Skip output
* Create Temporary Layer (``TEMPORARY_OUTPUT``)
* Save to File...
* Save to Geopackage...
* Save to PostGIS Table
The file encoding can also be changed here.
Outputs
.......
.. list-table::
:header-rows: 1
:widths: 20 20 20 40
:stub-columns: 0
* - Label
- Name
- Type
- Description
* - **Service area (boundary nodes)**
- ``OUTPUT``
- [vector: point]
- The output point layer with the service area boundary
nodes.
* - **Service area (lines)**
- ``OUTPUT_LINES``
- [vector: line]
- Line layer representing the parts of the network
that can be serviced by the start points, for the
given cost.
.. _qgisserviceareafrompoint:
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
..........
.. list-table::
:header-rows: 1
:widths: 20 20 20 40
:stub-columns: 0
* - Label
- Name
- Type
- Description
* - **Vector layer representing the network**
- ``INPUT``
- [vector: line]
- Line vector layer representing the network to be covered
* - **Start point (x, y)**
- ``START_POINT``
- [coordinates]
- Coordinate of the point to calculate the service
area around.
* - **Path type to calculate**
- ``STRATEGY``
- [enumeration]
Default: 0
- The type of path to calculate. One of:
* 0 --- Shortest
* 1 --- Fastest
* - **Travel cost (distance for "Shortest", time for "Fastest"**
- ``TRAVEL_COST``
- [number]
Default: 0
- 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.
* - **Direction field**
Optional
- ``DIRECTION_FIELD``
- [tablefield: string]
Default: None
- 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**
Optional
- ``VALUE_FORWARD``
- [string]
Default: '' (empty string)
- Value set in the direction field to identify edges with a
forward direction
* - **Value for backward direction**
Optional
- ``VALUE_BACKWARD``
- [string]
Default: '' (empty string)
- Value set in the direction field to identify edges with a
backward direction
* - **Value for both directions**
Optional
- ``VALUE_BOTH``
- [string]
Default: '' (empty string)
- Value set in the direction field to identify
bidirectional edges
* - **Default direction**
Optional
- ``DEFAULT_DIRECTION``
- [enumeration]
Default: 2
- If a feature has no value set in the direction field or
if no direction field is set, then this direction value
is used. One of:
* 0 --- Forward direction
* 1 --- Backward direction
* 2 --- Both directions
* - **Speed field**
Optional
- ``SPEED_FIELD``
- [tablefield: string]
Default: None
- 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)**
Optional
- ``DEFAULT_SPEED``
- [number]
Default: 50
- Value to use to calculate the travel time if no speed
field is provided for an edge
* - **Topology tolerance**
Optional
- ``TOLERANCE``
- [number]
Default: 0
- Two lines with nodes closer than the specified
tolerance are considered connected
* - **Include upper/lower bound points**
- ``INCLUDE_BOUNDS``
- [boolean]
Default: False
- 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.
* - **Service area (lines)**
- ``OUTPUT_LINES``
- [vector: line]
Default: ``[Create temporary layer]``
- Specify the output line layer for the service area.
One of:
* Skip output
* Create Temporary Layer (``TEMPORARY_OUTPUT``)
* Save to File...
* Save to Geopackage...
* Save to PostGIS Table
The file encoding can also be changed here.
* - **Service area (boundary nodes)**
- ``OUTPUT``
- [vector: point]
Default: ``[Skip output]``
- Specify the output point layer for the service area
boundary nodes. One of:
* Skip output
* Create Temporary Layer (``TEMPORARY_OUTPUT``)
* Save to File...
* Save to Geopackage...
* Save to PostGIS Table
The file encoding can also be changed here.
Outputs
.......
.. list-table::
:header-rows: 1
:widths: 20 20 20 40
:stub-columns: 0
* - Label
- Name
- Type
- Description
* - **Service area (boundary nodes)**
- ``OUTPUT``
- [vector: point]
- The output point layer with the service area boundary
nodes.
* - **Service area (lines)**
- ``OUTPUT_LINES``
- [vector: line]
- Line layer representing the parts of the network
that can be serviced by the start point, for the
given cost.
.. _qgisshortestpathlayertopoint:
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
..........
.. list-table::
:header-rows: 1
:widths: 20 20 20 40
:stub-columns: 0
* - Label
- Name
- Type
- Description
* - **Vector layer representing network**
- ``INPUT``
- [vector: line]
- Line vector layer representing the network to be covered
* - **Path type to calculate**
- ``STRATEGY``
- [enumeration]
Default: 0
- The type of path to calculate. One of:
* 0 --- Shortest
* 1 --- Fastest
* - **Vector layer with start points**
- ``START_POINTS``
- [vector: point]
- Point vector layer whose features are used as start
points of the routes
* - **End point (x, y)**
- ``END_POINT``
- [coordinates]
- Point feature representing the end point of the routes
* - **Direction field**
Optional
- ``DIRECTION_FIELD``
- [tablefield: string]
Default: None
- 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**
Optional
- ``VALUE_FORWARD``
- [string]
Default: '' (empty string)
- Value set in the direction field to identify edges with a
forward direction
* - **Value for backward direction**
Optional
- ``VALUE_BACKWARD``
- [string]
Default: '' (empty string)
- Value set in the direction field to identify edges with a
backward direction
* - **Value for both directions**
Optional
- ``VALUE_BOTH``
- [string]
Default: '' (empty string)
- Value set in the direction field to identify
bidirectional edges
* - **Default direction**
Optional
- ``DEFAULT_DIRECTION``
- [enumeration]
Default: 2
- If a feature has no value set in the direction field or
if no direction field is set, then this direction value
is used. One of:
* 0 --- Forward direction
* 1 --- Backward direction
* 2 --- Both directions
* - **Speed field**
Optional
- ``SPEED_FIELD``
- [tablefield: string]
Default: None
- 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)**
Optional
- ``DEFAULT_SPEED``
- [number]
Default: 50
- Value to use to calculate the travel time if no speed
field is provided for an edge
* - **Topology tolerance**
Optional
- ``TOLERANCE``
- [number]
Default: 0
- Two lines with nodes closer than the specified
tolerance are considered connected
* - **Shortest path**
- ``OUTPUT``
- [vector: line]
- Specify the output line layer for the shortest paths.
One of:
* Skip output
* Create Temporary Layer (``TEMPORARY_OUTPUT``)
* Save to File...
* Save to Geopackage...
* Save to PostGIS Table
The file encoding can also be changed here.
Outputs
.......
.. list-table::
:header-rows: 1
:widths: 20 20 20 40
:stub-columns: 0
* - Label
- Name
- Type
- Description
* - **Shortest path**
- ``OUTPUT``
- [vector: line]
- Line layer of the shortest or fastest path
from each of the start points to the end point
.. _qgisshortestpathpointtolayer:
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
..........
.. list-table::
:header-rows: 1
:widths: 20 20 20 40
:stub-columns: 0
* - Label
- Name
- Type
- Description
* - **Vector layer representing network**
- ``INPUT``
- [vector: line]
- Line vector layer representing the network to be covered
* - **Path type to calculate**
- ``STRATEGY``
- [enumeration]
Default: 0
- The type of path to calculate. One of:
* 0 --- Shortest
* 1 --- Fastest
* - **Start point (x, y)**
- ``START_POINT``
- [coordinates]
- Point feature representing the start point of the routes
* - **Vector layer with end points**
- ``END_POINTS``
- [vector: point]
- Point vector layer whose features are used as end
points of the routes
* - **Direction field**
Optional
- ``DIRECTION_FIELD``
- [tablefield: string]
Default: None
- 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**
Optional
- ``VALUE_FORWARD``
- [string]
Default: '' (empty string)
- Value set in the direction field to identify edges with a
forward direction
* - **Value for backward direction**
Optional
- ``VALUE_BACKWARD``
- [string]
Default: '' (empty string)
- Value set in the direction field to identify edges with a
backward direction
* - **Value for both directions**
Optional
- ``VALUE_BOTH``
- [string]
Default: '' (empty string)
- Value set in the direction field to identify
bidirectional edges
* - **Default direction**
Optional
- ``DEFAULT_DIRECTION``
- [enumeration]
Default: 2
- If a feature has no value set in the direction field or
if no direction field is set, then this direction value
is used. One of:
* 0 --- Forward direction
* 1 --- Backward direction
* 2 --- Both directions
* - **Speed field**
Optional
- ``SPEED_FIELD``
- [tablefield: string]
Default: None
- 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)**
Optional
- ``DEFAULT_SPEED``
- [number]
Default: 50
- Value to use to calculate the travel time if no speed
field is provided for an edge
* - **Topology tolerance**
Optional
- ``TOLERANCE``
- [number]
Default: 0
- Two lines with nodes closer than the specified
tolerance are considered connected
* - **Shortest path**
- ``OUTPUT``
- [vector: line]
- Specify the output line layer for the shortest paths.
One of:
* Create Temporary Layer (``TEMPORARY_OUTPUT``)
* Save to File...
* Save to Geopackage...
* Save to PostGIS Table
The file encoding can also be changed here.
Outputs
.......
.. list-table::
:header-rows: 1
:widths: 20 20 20 40
:stub-columns: 0
* - Label
- Name
- Type
- Description
* - **Shortest path**
- ``OUTPUT``
- [vector: line]
- Line layer of the shortest or fastest path
from each of the start points to the end point
.. _qgisshortestpathpointtopoint:
Shortest path (point to point)
------------------------------
Computes the optimal (shortest or fastest) route between a given start point and a given end point.
Parameters
..........
.. list-table::
:header-rows: 1
:widths: 20 20 20 40
:stub-columns: 0
* - Label
- Name
- Type
- Description
* - **Vector layer representing network**
- ``INPUT``
- [vector: line]
- Line vector layer representing the network to be covered
* - **Path type to calculate**
- ``STRATEGY``
- [enumeration]
Default: 0
- The type of path to calculate. One of:
* 0 --- Shortest
* 1 --- Fastest
* - **Start point (x, y)**
- ``START_POINT``
- [coordinates]
- Point feature representing the start point of the routes
* - **End point (x, y)**
- ``END_POINT``
- [coordinates]
- Point feature representing the end point of the routes
* - **Direction field**
Optional
- ``DIRECTION_FIELD``
- [tablefield: string]
Default: None
- 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**
Optional
- ``VALUE_FORWARD``
- [string]
Default: '' (empty string)
- Value set in the direction field to identify edges with a
forward direction
* - **Value for backward direction**
Optional
- ``VALUE_BACKWARD``
- [string]
Default: '' (empty string)
- Value set in the direction field to identify edges with a
backward direction
* - **Value for both directions**
Optional
- ``VALUE_BOTH``
- [string]
Default: '' (empty string)
- Value set in the direction field to identify
bidirectional edges
* - **Default direction**
Optional
- ``DEFAULT_DIRECTION``
- [enumeration]
Default: 2
- If a feature has no value set in the direction field or
if no direction field is set, then this direction value
is used. One of:
* 0 --- Forward direction
* 1 --- Backward direction
* 2 --- Both directions
* - **Speed field**
Optional
- ``SPEED_FIELD``
- [tablefield: string]
Default: None
- 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)**
Optional
- ``DEFAULT_SPEED``
- [number]
Default: 50
- Value to use to calculate the travel time if no speed
field is provided for an edge
* - **Topology tolerance**
Optional
- ``TOLERANCE``
- [number]
Default: 0
- Two lines with nodes closer than the specified
tolerance are considered connected
* - **Shortest path**
- ``OUTPUT``
- [vector: line]
- Specify the output line layer for the shortest paths.
One of:
* Create Temporary Layer (``TEMPORARY_OUTPUT``)
* Save to File...
* Save to Geopackage...
* Save to PostGIS Table
The file encoding can also be changed here.
Outputs
.......
.. list-table::
:header-rows: 1
:widths: 20 20 20 40
:stub-columns: 0
* - Label
- Name
- Type
- Description
* - **Shortest path**
- ``OUTPUT``
- [vector: line]
- Line layer of the shortest or fastest path
from each of the start point to the end point