[SEDONA-533] Add ST_Polygonize (#1342)

* [TASK-19] Add ST_Polygonize (#142)

* add ST_Polygonize

* add docs

* Fix python test

* Fix tests

* fix python test

* fix python test

* fix tests

* Update docs

* fix test

* fix test

* fix test

* fix test

* fix tests

* fix tests

* fix test

* fix test

* fix test

* fix test

* Fix test

* Fix typo

* Fix docs

---------

Co-authored-by: Jia Yu <jiayu@wherobots.com>

* Update ST_Polygonize version to OSS Sedona 1.6.0

---------

Co-authored-by: Pranav Toggi <prantogg@gmail.com>

common/src/main/java/org/apache/sedona/common/Functions.java

@@ -41,6 +41,7 @@
 import org.locationtech.jts.operation.distance3d.Distance3DOp;
 import org.locationtech.jts.operation.linemerge.LineMerger;
 import org.locationtech.jts.operation.overlay.snap.GeometrySnapper;
+import org.locationtech.jts.operation.polygonize.Polygonizer;
 import org.locationtech.jts.operation.valid.IsSimpleOp;
 import org.locationtech.jts.operation.valid.IsValidOp;
 import org.locationtech.jts.operation.valid.TopologyValidationError;
@@ -1661,4 +1662,31 @@ public static String isValidReason(Geometry geom, int flag) {
             return error.toString();
         }
     }
+
+    /**
+     * This method takes a GeometryCollection and returns another GeometryCollection
+     * containing the polygons formed by the linework of a set of geometries.
+     * @param geometry A collection of Geometry objects that should contain only linestrings.
+     * @return A GeometryCollection containing the resultant polygons.
+     */
+    public static Geometry polygonize(Geometry geometry) {
+        if (geometry == null || geometry.isEmpty()) {
+            return GEOMETRY_FACTORY.createGeometryCollection(null);
+        }
+
+        if (geometry instanceof GeometryCollection) {
+            Polygonizer polygonizer = new Polygonizer();
+
+            for (int i = 0; i < geometry.getNumGeometries(); i++) {
+                polygonizer.add(geometry.getGeometryN(i));
+            }
+
+            Collection polygons = polygonizer.getPolygons();
+            Geometry[] polyArray = (Geometry[]) polygons.toArray(new Geometry[0]);
+
+            return GEOMETRY_FACTORY.createGeometryCollection(polyArray);
+        } else {
+            return GEOMETRY_FACTORY.createGeometryCollection(null);
+        }
+    }
 }

common/src/test/java/org/apache/sedona/common/FunctionsTest.java

@@ -1018,6 +1018,54 @@ public void spheroidArea() {
         assertEquals(4.036497016235249E11, Spheroid.area(geometryCollection), 0.1);
     }
 
+    @Test
+    public void pologonize() throws ParseException {
+        LineString line1 = GEOMETRY_FACTORY.createLineString(coordArray(180, 40, 30, 20, 20, 90));
+        LineString line2 = GEOMETRY_FACTORY.createLineString(coordArray(180, 40, 160, 160));
+        LineString line3 = GEOMETRY_FACTORY.createLineString(coordArray(80, 60, 120, 130, 150, 80));
+        LineString line4 = GEOMETRY_FACTORY.createLineString(coordArray(80, 60, 150, 80));
+        LineString line5 = GEOMETRY_FACTORY.createLineString(coordArray(20, 90, 70, 70, 80, 130));
+        LineString line6 = GEOMETRY_FACTORY.createLineString(coordArray(80, 130, 160, 160));
+        LineString line7 = GEOMETRY_FACTORY.createLineString(coordArray(20, 90, 20, 160, 70 ,190));
+        LineString line8 = GEOMETRY_FACTORY.createLineString(coordArray(70, 190, 80, 130));
+        LineString line9 = GEOMETRY_FACTORY.createLineString(coordArray(70, 190, 160, 160));
+
+        LineString line10 = GEOMETRY_FACTORY.createLineString(coordArray(0,0,0,1,0,2));
+        LineString line11 = GEOMETRY_FACTORY.createLineString(coordArray(4,2,4,1,4,0));
+        LineString line12 = GEOMETRY_FACTORY.createLineString(coordArray(4,0,3,0,2,0,1,0,0,0));
+        LineString line13 = GEOMETRY_FACTORY.createLineString(coordArray(2,0,2,1,2,2));
+        LineString line14 = GEOMETRY_FACTORY.createLineString(coordArray(2,2,2,3,2,4));
+        LineString line15 = GEOMETRY_FACTORY.createLineString(coordArray(0,2,1,2,2,2));
+        LineString line16 = GEOMETRY_FACTORY.createLineString(coordArray(2,2,3,2,4,2));
+        LineString line17 = GEOMETRY_FACTORY.createLineString(coordArray(0,2,1,3,2,4));
+        LineString line18 = GEOMETRY_FACTORY.createLineString(coordArray(2,4,3,3,4,2));
+
+        GeometryCollection geometryCollection1 = GEOMETRY_FACTORY.createGeometryCollection(new Geometry[] {line1, line2, line3, line4, line5, line6, line7, line8, line9});
+        GeometryCollection geometryCollection2 = GEOMETRY_FACTORY.createGeometryCollection(new Geometry[] {line10, line11, line12, line13, line14, line15, line16, line17, line18});
+        GeometryCollection geometryCollection3 = GEOMETRY_FACTORY.createGeometryCollection(new Geometry[] {line10, line11, line12, line13, line15, line16});
+        GeometryCollection geometryCollection4 = GEOMETRY_FACTORY.createGeometryCollection(new Geometry[] {line13, line14, line15, line16, line17, line18});
+
+        Geometry expected1 = geomFromEWKT("GEOMETRYCOLLECTION (POLYGON ((20 90, 20 160, 70 190, 80 130, 70 70, 20 90)), POLYGON ((20 90, 70 70, 80 130, 160 160, 180 40, 30 20, 20 90), (80 60, 150 80, 120 130, 80 60)), POLYGON ((70 190, 160 160, 80 130, 70 190)), POLYGON ((80 60, 120 130, 150 80, 80 60)))");
+        Geometry result1 = Functions.polygonize(geometryCollection1);
+        result1.normalize();
+        assertEquals(expected1, result1);
+
+        Geometry expected2 = geomFromEWKT("GEOMETRYCOLLECTION (POLYGON ((0 0, 0 1, 0 2, 1 2, 2 2, 3 2, 4 2, 4 1, 4 0, 3 0, 2 0, 1 0, 0 0)), POLYGON ((0 2, 1 3, 2 4, 2 3, 2 2, 1 2, 0 2)), POLYGON ((2 2, 2 3, 2 4, 3 3, 4 2, 3 2, 2 2)))");
+        Geometry result2 = Functions.polygonize(geometryCollection2);
+        result2.normalize();
+        assertEquals(expected2, result2);
+
+        Geometry expected3 = geomFromEWKT("GEOMETRYCOLLECTION (POLYGON ((0 0, 0 1, 0 2, 1 2, 2 2, 3 2, 4 2, 4 1, 4 0, 3 0, 2 0, 1 0, 0 0)))");
+        Geometry result3 = Functions.polygonize(geometryCollection3);
+        result3.normalize();
+        assertEquals(expected3, result3);
+
+        Geometry expected4 = geomFromEWKT("GEOMETRYCOLLECTION (POLYGON ((0 2, 1 3, 2 4, 2 3, 2 2, 1 2, 0 2)), POLYGON ((2 2, 2 3, 2 4, 3 3, 4 2, 3 2, 2 2)))");
+        Geometry result4 = Functions.polygonize(geometryCollection4);
+        result4.normalize();
+        assertEquals(expected4, result4);
+    }
+
     @Test
     public void spheroidLength() {
         Point point = GEOMETRY_FACTORY.createPoint(new Coordinate(90, 0));

docs/api/flink/Function.md

@@ -2405,6 +2405,29 @@ Output:
 POLYGON((75 29 1, 77 29 2, 77 29 3, 75 29 1))
 ```
 
+## ST_Polygonize
+
+Introduction: Generates a GeometryCollection composed of polygons that are formed from the linework of an input GeometryCollection. When the input does not contain any linework that forms a polygon, the function will return an empty GeometryCollection.
+
+!!!note
+    `ST_Polygonize` function assumes that the input geometries form a valid and simple closed linestring that can be turned into a polygon. If the input geometries are not noded or do not form such linestrings, the resulting GeometryCollection may be empty or may not contain the expected polygons.
+
+Format: `ST_Polygonize(geom: Geometry)`
+
+Since: `v1.6.0`
+
+Example:
+
+```sql
+SELECT ST_AsText(ST_Polygonize(ST_GeomFromEWKT('GEOMETRYCOLLECTION (LINESTRING (2 0, 2 1, 2 2), LINESTRING (2 2, 2 3, 2 4), LINESTRING (0 2, 1 2, 2 2), LINESTRING (2 2, 3 2, 4 2), LINESTRING (0 2, 1 3, 2 4), LINESTRING (2 4, 3 3, 4 2))')));
+```
+
+Output:
+
+```
+GEOMETRYCOLLECTION (POLYGON ((0 2, 1 3, 2 4, 2 3, 2 2, 1 2, 0 2)), POLYGON ((2 2, 2 3, 2 4, 3 3, 4 2, 3 2, 2 2)))
+```
+
 ## ST_ReducePrecision
 
 Introduction: Reduce the decimals places in the coordinates of the geometry to the given number of decimal places. The last decimal place will be rounded.

docs/api/snowflake/vector-data/Function.md

@@ -1867,6 +1867,27 @@ Output:
 POLYGON((75 29 1, 77 29 2, 77 29 3, 75 29 1))
 ```
 
+## ST_Polygonize
+
+Introduction: Generates a GeometryCollection composed of polygons that are formed from the linework of an input GeometryCollection. When the input does not contain any linework that forms a polygon, the function will return an empty GeometryCollection.
+
+!!!note
+    `ST_Polygonize` function assumes that the input geometries form a valid and simple closed linestring that can be turned into a polygon. If the input geometries are not noded or do not form such linestrings, the resulting GeometryCollection may be empty or may not contain the expected polygons.
+
+Format: `ST_Polygonize(geom: Geometry)`
+
+Example:
+
+```sql
+SELECT ST_AsText(ST_Polygonize(ST_GeomFromEWKT('GEOMETRYCOLLECTION (LINESTRING (2 0, 2 1, 2 2), LINESTRING (2 2, 2 3, 2 4), LINESTRING (0 2, 1 2, 2 2), LINESTRING (2 2, 3 2, 4 2), LINESTRING (0 2, 1 3, 2 4), LINESTRING (2 4, 3 3, 4 2))')));
+```
+
+Output:
+
+```
+GEOMETRYCOLLECTION (POLYGON ((0 2, 1 3, 2 4, 2 3, 2 2, 1 2, 0 2)), POLYGON ((2 2, 2 3, 2 4, 3 3, 4 2, 3 2, 2 2)))
+```
+
 ## ST_ReducePrecision
 
 Introduction: Reduce the decimals places in the coordinates of the geometry to the given number of decimal places. The last decimal place will be rounded. This function was called ST_PrecisionReduce in versions prior to v1.5.0.

docs/api/sql/Function.md

@@ -2413,6 +2413,29 @@ Output:
 POLYGON((75 29 1, 77 29 2, 77 29 3, 75 29 1))
 ```
 
+## ST_Polygonize
+
+Introduction: Generates a GeometryCollection composed of polygons that are formed from the linework of an input GeometryCollection. When the input does not contain any linework that forms a polygon, the function will return an empty GeometryCollection.
+
+!!!note
+    `ST_Polygonize` function assumes that the input geometries form a valid and simple closed linestring that can be turned into a polygon. If the input geometries are not noded or do not form such linestrings, the resulting GeometryCollection may be empty or may not contain the expected polygons.
+
+Format: `ST_Polygonize(geom: Geometry)`
+
+Since: `v1.6.0`
+
+Example:
+
+```sql
+SELECT ST_AsText(ST_Polygonize(ST_GeomFromEWKT('GEOMETRYCOLLECTION (LINESTRING (2 0, 2 1, 2 2), LINESTRING (2 2, 2 3, 2 4), LINESTRING (0 2, 1 2, 2 2), LINESTRING (2 2, 3 2, 4 2), LINESTRING (0 2, 1 3, 2 4), LINESTRING (2 4, 3 3, 4 2))')));
+```
+
+Output:
+
+```
+GEOMETRYCOLLECTION (POLYGON ((0 2, 1 3, 2 4, 2 3, 2 2, 1 2, 0 2)), POLYGON ((2 2, 2 3, 2 4, 3 3, 4 2, 3 2, 2 2)))
+```
+
 ## ST_ReducePrecision
 
 Introduction: Reduce the decimals places in the coordinates of the geometry to the given number of decimal places. The last decimal place will be rounded. This function was called ST_PrecisionReduce in versions prior to v1.5.0.

flink/src/main/java/org/apache/sedona/flink/Catalog.java

@@ -123,6 +123,7 @@ public static UserDefinedFunction[] getFuncs() {
                 new Functions.ST_LineSubstring(),
                 new Functions.ST_MakeLine(),
                 new Functions.ST_Polygon(),
+                new Functions.ST_Polygonize(),
                 new Functions.ST_MakePolygon(),
                 new Functions.ST_MakeValid(),
                 new Functions.ST_MinimumBoundingCircle(),

flink/src/main/java/org/apache/sedona/flink/expressions/Functions.java

@@ -783,6 +783,14 @@ public Geometry eval(@DataTypeHint(value = "RAW", bridgedTo = org.locationtech.j
         }
     }
 
+    public static class ST_Polygonize extends ScalarFunction {
+        @DataTypeHint(value = "RAW", bridgedTo = org.locationtech.jts.geom.Geometry.class)
+        public Geometry eval(@DataTypeHint(value = "RAW", bridgedTo = org.locationtech.jts.geom.Geometry.class) Object o1) {
+            Geometry geom = (Geometry) o1;
+            return org.apache.sedona.common.Functions.polygonize(geom);
+        }
+    }
+
     public static class ST_MakeValid extends ScalarFunction {
         @DataTypeHint(value = "RAW", bridgedTo = org.locationtech.jts.geom.Geometry.class)
         public Geometry eval(@DataTypeHint(value = "RAW", bridgedTo = org.locationtech.jts.geom.Geometry.class) Object o,

flink/src/test/java/org/apache/sedona/flink/FunctionTest.java

@@ -17,6 +17,7 @@
 import org.apache.commons.lang3.tuple.Pair;
 import org.apache.flink.table.api.Table;
 import org.apache.flink.table.planner.expressions.In;
+import org.apache.sedona.flink.expressions.Constructors;
 import org.apache.sedona.flink.expressions.Functions;
 import org.apache.sedona.flink.expressions.FunctionsGeoTools;
 import org.geotools.referencing.CRS;
@@ -28,6 +29,7 @@
 import org.locationtech.jts.operation.buffer.BufferParameters;
 import org.opengis.referencing.FactoryException;
 import org.opengis.referencing.crs.CoordinateReferenceSystem;
+import scala.collection.immutable.Stream;
 
 import java.util.Arrays;
 import java.util.List;
@@ -935,6 +937,16 @@ public void testPolygon() {
         assertEquals(4236, result.getSRID());
     }
 
+    @Test
+    public void testPolygonize() {
+        Table table = tableEnv.sqlQuery("SELECT ST_GeomFromEWKT('GEOMETRYCOLLECTION (LINESTRING (180 40, 30 20, 20 90), LINESTRING (180 40, 160 160), LINESTRING (80 60, 120 130, 150 80), LINESTRING (80 60, 150 80), LINESTRING (20 90, 70 70, 80 130), LINESTRING (80 130, 160 160), LINESTRING (20 90, 20 160, 70 190), LINESTRING (70 190, 80 130), LINESTRING (70 190, 160 160))') AS geom");
+        table = table.select(call(Functions.ST_Polygonize.class.getSimpleName(), $("geom")));
+        Geometry result = (Geometry) first(table).getField(0);
+        result.normalize();
+        String expected = "GEOMETRYCOLLECTION (POLYGON ((20 90, 20 160, 70 190, 80 130, 70 70, 20 90)), POLYGON ((20 90, 70 70, 80 130, 160 160, 180 40, 30 20, 20 90), (80 60, 150 80, 120 130, 80 60)), POLYGON ((70 190, 160 160, 80 130, 70 190)), POLYGON ((80 60, 120 130, 150 80, 80 60)))";
+        assertEquals(expected, result.toString());
+    }
+
     @Test
     public void testMakePolygon() {
         Table table = tableEnv.sqlQuery("SELECT ST_GeomFromWKT('LINESTRING (0 0, 1 0, 1 1, 0 0)') AS line");

python/sedona/sql/st_functions.py

@@ -86,6 +86,7 @@
     "ST_LineSubstring",
     "ST_MakeLine",
     "ST_Polygon"
+    "ST_Polygonize"
     "ST_MakePolygon",
     "ST_MakeValid",
     "ST_MinimumBoundingCircle",
@@ -996,6 +997,17 @@ def ST_Polygon(line_string: ColumnOrName, srid: ColumnOrNameOrNumber) -> Column:
     """
     return _call_st_function("ST_Polygon", (line_string, srid))
 
+@validate_argument_types
+def ST_Polygonize(geometry: ColumnOrName) -> Column:
+    """Generates a GeometryCollection composed of polygons that are formed from the linework of a set of input geometries.
+
+    :param geometry: input geometry of type GeometryCollection
+    :type geometry: ColumnOrName
+    :return: GeometryCollection geometry column created from the input geometry.
+    :rtype: Column
+    """
+    return _call_st_function("ST_Polygonize", (geometry))
+
 @validate_argument_types
 def ST_MakePolygon(line_string: ColumnOrName, holes: Optional[ColumnOrName] = None) -> Column:
     """Create a polygon geometry from a linestring describing the exterior ring as well as an array of linestrings describing holes.

python/tests/sql/test_dataframe_api.py

@@ -131,6 +131,7 @@
     (stf.ST_MakeValid, ("geom",), "invalid_geom", "", "MULTIPOLYGON (((1 5, 3 3, 1 1, 1 5)), ((5 3, 7 5, 7 1, 5 3)))"),
     (stf.ST_MakeLine, ("line1", "line2"), "two_lines", "", "LINESTRING (0 0, 1 1, 0 0, 3 2)"),
     (stf.ST_Polygon, ("geom", 4236), "closed_linestring_geom", "", "POLYGON ((0 0, 1 0, 1 1, 0 0))"),
+    (stf.ST_Polygonize, ("geom",), "noded_linework", "ST_Normalize(geom)", "GEOMETRYCOLLECTION (POLYGON ((0 2, 1 3, 2 4, 2 3, 2 2, 1 2, 0 2)), POLYGON ((2 2, 2 3, 2 4, 3 3, 4 2, 3 2, 2 2)))"),
     (stf.ST_MakePolygon, ("geom",), "closed_linestring_geom", "", "POLYGON ((0 0, 1 0, 1 1, 0 0))"),
     (stf.ST_MinimumBoundingCircle, ("line", 8), "linestring_geom", "ST_ReducePrecision(geom, 2)", "POLYGON ((4.95 -0.49, 4.81 -0.96, 4.58 -1.39, 4.27 -1.77, 3.89 -2.08, 3.46 -2.31, 2.99 -2.45, 2.5 -2.5, 2.01 -2.45, 1.54 -2.31, 1.11 -2.08, 0.73 -1.77, 0.42 -1.39, 0.19 -0.96, 0.05 -0.49, 0 0, 0.05 0.49, 0.19 0.96, 0.42 1.39, 0.73 1.77, 1.11 2.08, 1.54 2.31, 2.01 2.45, 2.5 2.5, 2.99 2.45, 3.46 2.31, 3.89 2.08, 4.27 1.77, 4.58 1.39, 4.81 0.96, 4.95 0.49, 5 0, 4.95 -0.49))"),
     (stf.ST_MinimumBoundingCircle, ("line", 2), "linestring_geom", "ST_ReducePrecision(geom, 2)", "POLYGON ((4.27 -1.77, 2.5 -2.5, 0.73 -1.77, 0 0, 0.73 1.77, 2.5 2.5, 4.27 1.77, 5 0, 4.27 -1.77))"),
@@ -467,6 +468,8 @@ def base_df(self, request):
             return TestDataFrameAPI.spark.sql("SELECT array(ST_GeomFromWKT('POLYGON ((-3 -3, 3 -3, 3 3, -3 3, -3 -3))'), ST_GeomFromWKT('POLYGON ((-2 1, 2 1, 2 4, -2 4, -2 1))')) as polys")
         elif request.param == "poly_and_line":
             return TestDataFrameAPI.spark.sql("SELECT ST_GeomFromWKT('POLYGON((2.6 12.5, 2.6 20.0, 12.6 20.0, 12.6 12.5, 2.6 12.5 ))') as poly, ST_GeomFromWKT('LINESTRING (0.5 10.7, 5.4 8.4, 10.1 10.0)') as line")
+        elif request.param == "noded_linework":
+            return TestDataFrameAPI.spark.sql("SELECT ST_GeomFromWKT('GEOMETRYCOLLECTION (LINESTRING (2 0, 2 1, 2 2), LINESTRING (2 2, 2 3, 2 4), LINESTRING (0 2, 1 2, 2 2), LINESTRING (2 2, 3 2, 4 2), LINESTRING (0 2, 1 3, 2 4), LINESTRING (2 4, 3 3, 4 2))') as geom")
         raise ValueError(f"Invalid base_df name passed: {request.param}")
 
     def _id_test_configuration(val):

python/tests/sql/test_function.py

@@ -973,6 +973,30 @@ def test_st_polygon(self):
         for actual, expected in result:
             assert actual == expected
 
+    def test_st_polygonize(self):
+        # Given
+        geometry_df = self.spark.createDataFrame(
+            [
+                # Adding only the input that will result in a non-null polygon
+                ["GEOMETRYCOLLECTION (LINESTRING (2 0, 2 1, 2 2), LINESTRING (2 2, 2 3, 2 4), LINESTRING (0 2, 1 2, 2 2), LINESTRING (2 2, 3 2, 4 2), LINESTRING (0 2, 1 3, 2 4), LINESTRING (2 4, 3 3, 4 2))", "GEOMETRYCOLLECTION (POLYGON ((0 2, 1 3, 2 4, 2 3, 2 2, 1 2, 0 2)), POLYGON ((2 2, 2 3, 2 4, 3 3, 4 2, 3 2, 2 2)))"]
+            ]
+        ).selectExpr("ST_GeomFromText(_1) AS geom", "_2 AS expected")
+
+        # When calling st_polygonize
+        geom_poly = geometry_df.withColumn("actual", expr("st_normalize(st_polygonize(geom))"))
+
+        # Then only based on closed linestring geom is created
+        geom_poly.filter("actual IS NOT NULL").selectExpr("ST_AsText(actual)", "expected"). \
+            show()
+        result = geom_poly.filter("actual IS NOT NULL").selectExpr("ST_AsText(actual)", "expected"). \
+            collect()
+
+        assert result.__len__() == 1
+
+        for actual, expected in result:
+            assert actual == expected
+
+
     def test_st_make_polygon(self):
         # Given
         geometry_df = self.spark.createDataFrame(

snowflake-tester/src/test/java/org/apache/sedona/snowflake/snowsql/TestFunctions.java

@@ -715,6 +715,16 @@ public void test_ST_Polygon() {
         );
     }
 
+    @Test
+    public void test_ST_Polygonize() {
+        registerUDF("ST_Polygonize", byte[].class);
+        registerUDF("ST_Area", byte[].class);
+        verifySqlSingleRes(
+                "select sedona.ST_Area(sedona.ST_Polygonize(sedona.ST_GeomFromText('GEOMETRYCOLLECTION (LINESTRING (2 0, 2 1, 2 2), LINESTRING (2 2, 2 3, 2 4), LINESTRING (0 2, 1 2, 2 2), LINESTRING (2 2, 3 2, 4 2), LINESTRING (0 2, 1 3, 2 4), LINESTRING (2 4, 3 3, 4 2))')))",
+                4.0
+        );
+    }
+
     @Test
     public void test_ST_PrecisionReduce() {
         registerUDF("ST_PrecisionReduce", byte[].class, int.class);

snowflake-tester/src/test/java/org/apache/sedona/snowflake/snowsql/TestFunctionsV2.java

@@ -665,6 +665,16 @@ public void test_ST_Polygon() {
         );
     }
 
+    @Test
+    public void test_ST_Polygonize() {
+        registerUDFV2("ST_Polygonize", String.class);
+        registerUDFV2("ST_Area", String.class);
+        verifySqlSingleRes(
+                "select ST_Area(sedona.ST_Polygonize(ST_GeometryFromWKT('GEOMETRYCOLLECTION (LINESTRING (2 0, 2 1, 2 2), LINESTRING (2 2, 2 3, 2 4), LINESTRING (0 2, 1 2, 2 2), LINESTRING (2 2, 3 2, 4 2), LINESTRING (0 2, 1 3, 2 4), LINESTRING (2 4, 3 3, 4 2))')))",
+                4.0
+        );
+    }
+
     @Test
     public void test_ST_PrecisionReduce() {
         registerUDFV2("ST_PrecisionReduce", String.class, int.class);

snowflake/src/main/java/org/apache/sedona/snowflake/snowsql/UDFs.java

@@ -947,6 +947,15 @@ public static byte[] ST_Polygon(byte[] geometry, int srid) {
         );
     }
 
+    @UDFAnnotations.ParamMeta(argNames = {"geometry"})
+    public static byte[] ST_Polygonize(byte[] geometry) {
+        return GeometrySerde.serialize(
+                Functions.polygonize(
+                        GeometrySerde.deserialize(geometry)
+                )
+        );
+    }
+
     @UDFAnnotations.ParamMeta(argNames = {"minX", "minY", "maxX", "maxY"})
     public static byte[] ST_PolygonFromEnvelope(double minX, double minY, double maxX, double maxY) {
         return GeometrySerde.serialize(