pyspark.sql.functions.flatten¶

pyspark.sql.functions.flatten(col: ColumnOrName) → pyspark.sql.column.Column[source]¶

Collection function: creates a single array from an array of arrays. If a structure of nested arrays is deeper than two levels, only one level of nesting is removed.

New in version 2.4.0.

Changed in version 3.4.0: Supports Spark Connect.

Parameters

colColumn or str: name of column or expression

Returns

Column: flattened array.

Examples

>>> df = spark.createDataFrame([([[1, 2, 3], [4, 5], [6]],), ([None, [4, 5]],)], ['data'])
>>> df.show(truncate=False)
+------------------------+
|data                    |
+------------------------+
|[[1, 2, 3], [4, 5], [6]]|
|[null, [4, 5]]          |
+------------------------+
>>> df.select(flatten(df.data).alias('r')).show()
+------------------+
|                 r|
+------------------+
|[1, 2, 3, 4, 5, 6]|
|              null|
+------------------+

pyspark.sql.functions.reverse pyspark.sql.functions.sequence