Teradata Package for Python Function Reference | 17.10 - is_ring - Teradata Package for Python
Teradata® Package for Python Function Reference
- Product
- Teradata Package for Python
- Release Number
- 17.10
- Published
- April 2022
- Language
- English (United States)
- Last Update
- 2022-08-19
- Product Category
- Teradata Vantage
- teradataml.geospatial.geodataframe.GeoDataFrame.is_ring
- DESCRIPTION:
Tests if a Geometry type that represents an ST_LineString or a
GeoSequence value is a ring.
Note:
* is_ring returns zero if the geometry value passed to it is an
empty set.
PARAMETERS:
None
SUPPORTED GEOMETRY TYPES:
ST_LineString or GeoSequence
RAISES:
TypeError, ValueError, TeradataMlException
RETURNS:
GeoDataFrame
Resultant column contains:
* 1, if the ST_LineString or GeoSequence value is simple (has no
anomalous geometric points, such as self intersection tangency)
and is closed (the start point of the ST_LineString value is
equal to the end point)
* 0, in all other cases.
EXAMPLES:
from teradataml import GeoDataFrame, load_example_data
# Load example data.
load_example_data("geodataframe", "sample_shapes")
# Create a GeoDataFrame.
gdf = GeoDataFrame("sample_shapes")
gdf = gdf.select(["skey", "polygons", "linestrings"])[~gdf.skey.isin([1009, 1008, 1010, 1007])]
gdf
# Example 1: Check if geometries in column 'linestrings' is ring or not.
# Let's check where the GeoDataFrame.geometry property points to.
print(gdf.geometry.name)
# Note: By default, GeoDataFrame.geometry property points to the first geometry column,
# in this case it is 'polygons'.
# Set the geometry property to 'linestrings' column.
gdf.geometry = gdf.linestrings
gdf.is_ring