Geospatial expressions
Points, Polygons, LineStrings, and other geospatial types.
GeoSpatialValue
GeoSpatialValue()
Methods
| Name | Description |
|---|---|
| area | Compute the area of a geospatial value. |
| as_binary | Get the geometry as well-known bytes (WKB) without the SRID data. |
| as_ewkb | Get the geometry as well-known bytes (WKB) with the SRID data. |
| as_ewkt | Get the geometry as well-known text (WKT) with the SRID data. |
| as_text | Get the geometry as well-known text (WKT) without the SRID data. |
| azimuth | Return the angle in radians from the horizontal of the vector defined by the inputs. |
| buffer | Return all points whose distance from this geometry is less than or equal to radius. |
| centroid | Returns the centroid of the geometry. |
| contains | Check if the geometry contains the right. |
| contains_properly | Check if the first geometry contains the second one. |
| covered_by | Check if the first geometry is covered by the second one. |
| covers | Check if the first geometry covers the second one. |
| crosses | Check if the geometries have at least one interior point in common. |
| d_fully_within | Check if self is entirely within distance from right. |
| d_within | Check if self is partially within distance from right. |
| difference | Return the difference of two geometries. |
| disjoint | Check if the geometries have no points in common. |
| distance | Compute the distance between two geospatial expressions. |
| end_point | Return the last point of a LINESTRING geometry as a POINT. |
| envelope | Returns a geometry representing the bounding box of self. |
| geo_equals | Check if the geometries are equal. |
| geometry_n | Get the 1-based Nth geometry of a multi geometry. |
| geometry_type | Get the type of a geometry. |
| intersection | Return the intersection of two geometries. |
| intersects | Check if the geometries share any points. |
| is_valid | Check if the geometry is valid. |
| length | Compute the length of a geospatial expression. |
| line_locate_point | Locate the distance a point falls along the length of a line. |
| line_merge | Merge a MultiLineString into a LineString. |
| line_substring | Clip a substring from a LineString. |
| max_distance | Returns the 2-dimensional max distance between two geometries in projected units. |
| n_points | Return the number of points in a geometry. Works for all geometries. |
| n_rings | Return the number of rings for polygons and multipolygons. |
| ordering_equals | Check if two geometries are equal and have the same point ordering. |
| overlaps | Check if the geometries share space, have the same dimension, and are not completely contained by each other. |
| perimeter | Compute the perimeter of a geospatial expression. |
| point_n | Return the Nth point in a single linestring in the geometry. |
| set_srid | Set the spatial reference identifier for the ST_Geometry. |
| simplify | Simplify a given geometry. |
| srid | Return the spatial reference identifier for the ST_Geometry. |
| start_point | Return the first point of a LINESTRING geometry as a POINT. |
| touches | Check if the geometries have at least one point in common, but do not intersect. |
| transform | Transform a geometry into a new SRID. |
| union | Merge two geometries into a union geometry. |
| within | Check if the first geometry is completely inside of the second. |
| x | Return the X coordinate of self, or NULL if not available. |
| x_max | Return the X maxima of a geometry. |
| x_min | Return the X minima of a geometry. |
| y | Return the Y coordinate of self, or NULL if not available. |
| y_max | Return the Y maxima of a geometry. |
| y_min | Return the Y minima of a geometry. |
area
area()
Compute the area of a geospatial value.
Returns
| Type | Description |
|---|---|
FloatingValue |
The area of self |
as_binary
as_binary()
Get the geometry as well-known bytes (WKB) without the SRID data.
Returns
| Type | Description |
|---|---|
BinaryValue |
Binary value |
as_ewkb
as_ewkb()
Get the geometry as well-known bytes (WKB) with the SRID data.
Returns
| Type | Description |
|---|---|
BinaryValue |
WKB value |
as_ewkt
as_ewkt()
Get the geometry as well-known text (WKT) with the SRID data.
Returns
| Type | Description |
|---|---|
StringValue |
String value |
as_text
as_text()
Get the geometry as well-known text (WKT) without the SRID data.
Returns
| Type | Description |
|---|---|
StringValue |
String value |
azimuth
azimuth(right)
Return the angle in radians from the horizontal of the vector defined by the inputs.
Angle is computed clockwise from down-to-up on the clock: 12=0; 3=PI/2; 6=PI; 9=3PI/2.
Parameters
| Name | Type | Description | Default |
|---|---|---|---|
right |
GeoSpatialValue | Right geometry | required |
Returns
| Type | Description |
|---|---|
FloatingValue |
azimuth |
buffer
buffer(radius)
Return all points whose distance from this geometry is less than or equal to radius.
Calculations are in the Spatial Reference System of this Geometry.
Parameters
| Name | Type | Description | Default |
|---|---|---|---|
radius |
float | ir.FloatingValue |
Floating expression | required |
Returns
| Type | Description |
|---|---|
| GeoSpatialValue | Geometry expression |
centroid
centroid()
Returns the centroid of the geometry.
Returns
| Type | Description |
|---|---|
PointValue |
The centroid |
contains
contains(right)
Check if the geometry contains the right.
Parameters
| Name | Type | Description | Default |
|---|---|---|---|
right |
GeoSpatialValue | Right geometry | required |
Returns
| Type | Description |
|---|---|
BooleanValue |
Whether self contains right |
contains_properly
contains_properly(right)
Check if the first geometry contains the second one.
Excludes common border points.
Parameters
| Name | Type | Description | Default |
|---|---|---|---|
right |
GeoSpatialValue | Right geometry | required |
Returns
| Type | Description |
|---|---|
BooleanValue |
Whether self contains right excluding border points. |
covered_by
covered_by(right)
Check if the first geometry is covered by the second one.
Parameters
| Name | Type | Description | Default |
|---|---|---|---|
right |
GeoSpatialValue | Right geometry | required |
Returns
| Type | Description |
|---|---|
BooleanValue |
Whether self is covered by right |
covers
covers(right)
Check if the first geometry covers the second one.
Parameters
| Name | Type | Description | Default |
|---|---|---|---|
right |
GeoSpatialValue | Right geometry | required |
Returns
| Type | Description |
|---|---|
BooleanValue |
Whether self covers right |
crosses
crosses(right)
Check if the geometries have at least one interior point in common.
Parameters
| Name | Type | Description | Default |
|---|---|---|---|
right |
GeoSpatialValue | Right geometry | required |
Returns
| Type | Description |
|---|---|
BooleanValue |
Whether self and right have at least one common interior point. |
d_fully_within
d_fully_within(right, distance)
Check if self is entirely within distance from right.
Parameters
| Name | Type | Description | Default |
|---|---|---|---|
right |
GeoSpatialValue | Right geometry | required |
distance |
ir.FloatingValue |
Distance to check | required |
Returns
| Type | Description |
|---|---|
BooleanValue |
Whether self is within a specified distance from right. |
d_within
d_within(right, distance)
Check if self is partially within distance from right.
Parameters
| Name | Type | Description | Default |
|---|---|---|---|
right |
GeoSpatialValue | Right geometry | required |
distance |
ir.FloatingValue |
Distance to check | required |
Returns
| Type | Description |
|---|---|
BooleanValue |
Whether self is partially within distance from right. |
difference
difference(right)
Return the difference of two geometries.
Parameters
| Name | Type | Description | Default |
|---|---|---|---|
right |
GeoSpatialValue | Right geometry | required |
Returns
| Type | Description |
|---|---|
| GeoSpatialValue | Difference of self and right |
disjoint
disjoint(right)
Check if the geometries have no points in common.
Parameters
| Name | Type | Description | Default |
|---|---|---|---|
right |
GeoSpatialValue | Right geometry | required |
Returns
| Type | Description |
|---|---|
BooleanValue |
Whether self and right are disjoint |
distance
distance(right)
Compute the distance between two geospatial expressions.
Parameters
| Name | Type | Description | Default |
|---|---|---|---|
right |
GeoSpatialValue | Right geometry or geography | required |
Returns
| Type | Description |
|---|---|
FloatingValue |
Distance between self and right |
end_point
end_point()
Return the last point of a LINESTRING geometry as a POINT.
Return NULL if the input parameter is not a LINESTRING
Returns
| Type | Description |
|---|---|
PointValue |
End point |
envelope
envelope()
Returns a geometry representing the bounding box of self.
Returns
| Type | Description |
|---|---|
PolygonValue |
A polygon |
geo_equals
geo_equals(right)
Check if the geometries are equal.
Parameters
| Name | Type | Description | Default |
|---|---|---|---|
right |
GeoSpatialValue | Right geometry | required |
Returns
| Type | Description |
|---|---|
BooleanValue |
Whether self equals right |
geometry_n
geometry_n(n)
Get the 1-based Nth geometry of a multi geometry.
Parameters
| Name | Type | Description | Default |
|---|---|---|---|
n |
int | ir.IntegerValue |
Nth geometry index | required |
Returns
| Type | Description |
|---|---|
| GeoSpatialValue | Geometry value |
geometry_type
geometry_type()
Get the type of a geometry.
Returns
| Type | Description |
|---|---|
StringValue |
String representing the type of self. |
intersection
intersection(right)
Return the intersection of two geometries.
Parameters
| Name | Type | Description | Default |
|---|---|---|---|
right |
GeoSpatialValue | Right geometry | required |
Returns
| Type | Description |
|---|---|
| GeoSpatialValue | Intersection of self and right |
intersects
intersects(right)
Check if the geometries share any points.
Parameters
| Name | Type | Description | Default |
|---|---|---|---|
right |
GeoSpatialValue | Right geometry | required |
Returns
| Type | Description |
|---|---|
BooleanValue |
Whether self intersects right |
is_valid
is_valid()
Check if the geometry is valid.
Returns
| Type | Description |
|---|---|
BooleanValue |
Whether self is valid |
length
length()
Compute the length of a geospatial expression.
Returns
| Type | Description |
|---|---|
FloatingValue |
Length of self |
line_locate_point
line_locate_point(right)
Locate the distance a point falls along the length of a line.
Returns a float between zero and one representing the location of the closest point on the linestring to the given point, as a fraction of the total 2d line length.
Parameters
| Name | Type | Description | Default |
|---|---|---|---|
right |
PointValue |
Point geometry | required |
Returns
| Type | Description |
|---|---|
FloatingValue |
Fraction of the total line length |
line_merge
line_merge()
Merge a MultiLineString into a LineString.
Returns a (set of) LineString(s) formed by sewing together the constituent line work of a MultiLineString. If a geometry other than a LineString or MultiLineString is given, this will return an empty geometry collection.
Returns
| Type | Description |
|---|---|
| GeoSpatialValue | Merged linestrings |
line_substring
line_substring(start, end)
Clip a substring from a LineString.
Returns a linestring that is a substring of the input one, starting and ending at the given fractions of the total 2d length. The second and third arguments are floating point values between zero and one. This only works with linestrings.
Parameters
| Name | Type | Description | Default |
|---|---|---|---|
start |
ir.FloatingValue |
Start value | required |
end |
ir.FloatingValue |
End value | required |
Returns
| Type | Description |
|---|---|
LineStringValue |
Clipped linestring |
max_distance
max_distance(right)
Returns the 2-dimensional max distance between two geometries in projected units.
If self and right are the same geometry the function will return the distance between the two vertices most far from each other in that geometry.
Parameters
| Name | Type | Description | Default |
|---|---|---|---|
right |
GeoSpatialValue | Right geometry | required |
Returns
| Type | Description |
|---|---|
FloatingValue |
Maximum distance |
n_points
n_points()
Return the number of points in a geometry. Works for all geometries.
Returns
| Type | Description |
|---|---|
IntegerValue |
Number of points |
n_rings
n_rings()
Return the number of rings for polygons and multipolygons.
Outer rings are counted as well.
Returns
| Type | Description |
|---|---|
IntegerValue |
Number of rings |
ordering_equals
ordering_equals(right)
Check if two geometries are equal and have the same point ordering.
Returns true if the two geometries are equal and the coordinates are in the same order.
Parameters
| Name | Type | Description | Default |
|---|---|---|---|
right |
GeoSpatialValue | Right geometry | required |
Returns
| Type | Description |
|---|---|
BooleanValue |
Whether points and orderings are equal. |
overlaps
overlaps(right)
Check if the geometries share space, have the same dimension, and are not completely contained by each other.
Parameters
| Name | Type | Description | Default |
|---|---|---|---|
right |
GeoSpatialValue | Right geometry | required |
Returns
| Type | Description |
|---|---|
BooleanValue |
Overlaps indicator |
perimeter
perimeter()
Compute the perimeter of a geospatial expression.
Returns
| Type | Description |
|---|---|
FloatingValue |
Perimeter of self |
point_n
point_n(n)
Return the Nth point in a single linestring in the geometry.
Negative values are counted backwards from the end of the LineString, so that -1 is the last point. Returns NULL if there is no linestring in the geometry.
Parameters
| Name | Type | Description | Default |
|---|---|---|---|
n |
ir.IntegerValue |
Nth point index | required |
Returns
| Type | Description |
|---|---|
PointValue |
Nth point in self |
set_srid
set_srid(srid)
Set the spatial reference identifier for the ST_Geometry.
Parameters
| Name | Type | Description | Default |
|---|---|---|---|
srid |
ir.IntegerValue |
SRID integer value | required |
Returns
| Type | Description |
|---|---|
| GeoSpatialValue | self with SRID set to srid |
simplify
simplify(tolerance, preserve_collapsed)
Simplify a given geometry.
Parameters
| Name | Type | Description | Default |
|---|---|---|---|
tolerance |
ir.FloatingValue |
Tolerance | required |
preserve_collapsed |
ir.BooleanValue |
Whether to preserve collapsed geometries | required |
Returns
| Type | Description |
|---|---|
| GeoSpatialValue | Simplified geometry |
srid
srid()
Return the spatial reference identifier for the ST_Geometry.
Returns
| Type | Description |
|---|---|
IntegerValue |
SRID |
start_point
start_point()
Return the first point of a LINESTRING geometry as a POINT.
Return NULL if the input parameter is not a LINESTRING
Returns
| Type | Description |
|---|---|
PointValue |
Start point |
touches
touches(right)
Check if the geometries have at least one point in common, but do not intersect.
Parameters
| Name | Type | Description | Default |
|---|---|---|---|
right |
GeoSpatialValue | Right geometry | required |
Returns
| Type | Description |
|---|---|
BooleanValue |
Whether self and right are touching |
transform
transform(srid)
Transform a geometry into a new SRID.
Parameters
| Name | Type | Description | Default |
|---|---|---|---|
srid |
ir.IntegerValue |
Integer expression | required |
Returns
| Type | Description |
|---|---|
| GeoSpatialValue | Transformed geometry |
union
union(right)
Merge two geometries into a union geometry.
Returns the pointwise union of the two geometries. This corresponds to the non-aggregate version the PostGIS ST_Union.
Parameters
| Name | Type | Description | Default |
|---|---|---|---|
right |
GeoSpatialValue | Right geometry | required |
Returns
| Type | Description |
|---|---|
| GeoSpatialValue | Union of geometries |
within
within(right)
Check if the first geometry is completely inside of the second.
Parameters
| Name | Type | Description | Default |
|---|---|---|---|
right |
GeoSpatialValue | Right geometry | required |
Returns
| Type | Description |
|---|---|
BooleanValue |
Whether self is in right. |
x
x()
Return the X coordinate of self, or NULL if not available.
Input must be a point.
Returns
| Type | Description |
|---|---|
FloatingValue |
X coordinate of self |
x_max
x_max()
Return the X maxima of a geometry.
Returns
| Type | Description |
|---|---|
FloatingValue |
X maxima |
x_min
x_min()
Return the X minima of a geometry.
Returns
| Type | Description |
|---|---|
FloatingValue |
X minima |
y
y()
Return the Y coordinate of self, or NULL if not available.
Input must be a point.
Returns
| Type | Description |
|---|---|
FloatingValue |
Y coordinate of self |
y_max
y_max()
Return the Y maxima of a geometry.
Returns
| Type | Description |
|---|---|
FloatingValue |
Y maxima |
y_min
y_min()
Return the Y minima of a geometry.
Returns
| Type | Description |
|---|---|
FloatingValue |
Y minima |
GeoSpatialColumn
GeoSpatialColumn()
Methods
| Name | Description |
|---|---|
| unary_union | Aggregate a set of geometries into a union. |
unary_union
unary_union()
Aggregate a set of geometries into a union.
This corresponds to the aggregate version of the PostGIS ST_Union. We give it a different name (following the corresponding method in GeoPandas) to avoid name conflicts with the non-aggregate version.
Returns
| Type | Description |
|---|---|
GeoSpatialScalar |
Union of geometries |