define_geoattribute {rolap}

Define geoattribute of a dimension

Description

Define a set of attributes as a dimension's geoattribute. The set of attribute values must uniquely designate the instances of the given geographic layer.

Usage

define_geoattribute(db, dimension, attribute, from_layer, by, from_attribute)

## S3 method for class 'star_database'
define_geoattribute(
  db,
  dimension = NULL,
  attribute = NULL,
  from_layer = NULL,
  by = NULL,
  from_attribute = NULL
)

Arguments

db

A star_database object.

dimension

A string, dimension name.

attribute

A vector, attribute names.

from_layer

A sf object.

by

a vector of correspondence of attributes of the dimension with the sf layer structure.

from_attribute

A vector, attribute names.

Details

The definition can be done in two ways: Associates the instances of the attributes with the instances of a geographic layer or defines it from the geometry of previously defined geographic attributes.

Multiple attributes can be specified in the attribute parameter, the geographical attribute is the combination of all of them.

If defined from a layer (from_layer parameter), additionally the attributes used for the join between the tables (dimension and layer tables) must be indicated (by parameter).

If defined from another attribute, it should have the same or finer granularity, to obtain the result by grouping its instances. The considered attribute can be the pair that defines longitude and latitude.

If other geographic information has previously been associated with that attribute, the new information is considered and previous instances for which no new information is provided are also added.

If the geometry provided is polygons, a point layer is also generated.

Value

A star_database object.

See Also

Other star database geographic attributes: check_geoattribute_geometry(), get_geoattribute_geometries(), get_geoattributes(), get_layer_geometry(), get_point_geometry(), summarize_layer()

Examples

db <- mrs_db |>
  define_geoattribute(
    dimension = "where",
    attribute = "state",
    from_layer = us_layer_state,
    by = "STUSPS"
  ) |>
  define_geoattribute(
    dimension = "where",
    attribute = "region",
    from_attribute = "state"
  )  |>
  define_geoattribute(
    dimension = "where",
    attribute = "city",
    from_attribute = c("long", "lat")
  )