Selection

The purpose of selection step is to extract and standardize input data. A selection action is performed from an input layer according to a selection mode. A group and a class are assigned to each selection result.

Input layer
Input layer format (raster or vector) mus be set.
Input layer must be loaded in QGIS project to be available in BioDispersal.

Selection mode

- Vector
  - By field: input layer entities are classified accorindg to selected field values.
  - By expression: input layer entities are selected according to the expression. If expression is empty, every entity is selected.
- Raster
  - Create classes : generate classes from first band values and selected group
  - Resampling mode depends on data type ('Near' for discrete data, 'Average' for continuous data)

Groups
Merge groups gather data with same geometry (point, line, polygon or raster) according to thematic criterias (land use, roads, ...).

Classes
Friction classes are automatically generated by BioDispersal.