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# # Licensed to the Apache Software Foundation (ASF) under one or more # contributor license agreements. See the NOTICE file distributed with # this work for additional information regarding copyright ownership. # The ASF licenses this file to You under the Apache License, Version 2.0 # (the "License"); you may not use this file except in compliance with # the License. You may obtain a copy of the License at # # http://www.apache.org/licenses/LICENSE-2.0 # # Unless required by applicable law or agreed to in writing, software # distributed under the License is distributed on an "AS IS" BASIS, # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. # See the License for the specific language governing permissions and # limitations under the License. #
""" Min-in for pandas map operations. Currently, only :class:`DataFrame` can use this class. """
""" Maps an iterator of batches in the current :class:`DataFrame` using a Python native function that takes and outputs a pandas DataFrame, and returns the result as a :class:`DataFrame`.
The function should take an iterator of `pandas.DataFrame`\\s and return another iterator of `pandas.DataFrame`\\s. All columns are passed together as an iterator of `pandas.DataFrame`\\s to the function and the returned iterator of `pandas.DataFrame`\\s are combined as a :class:`DataFrame`. Each `pandas.DataFrame` size can be controlled by `spark.sql.execution.arrow.maxRecordsPerBatch`.
.. versionadded:: 3.0.0
Parameters ---------- func : function a Python native function that takes an iterator of `pandas.DataFrame`\\s, and outputs an iterator of `pandas.DataFrame`\\s. schema : :class:`pyspark.sql.types.DataType` or str the return type of the `func` in PySpark. The value can be either a :class:`pyspark.sql.types.DataType` object or a DDL-formatted type string.
Examples -------- >>> from pyspark.sql.functions import pandas_udf >>> df = spark.createDataFrame([(1, 21), (2, 30)], ("id", "age")) >>> def filter_func(iterator): ... for pdf in iterator: ... yield pdf[pdf.id == 1] >>> df.mapInPandas(filter_func, df.schema).show() # doctest: +SKIP +---+---+ | id|age| +---+---+ | 1| 21| +---+---+
Notes ----- This API is experimental
See Also -------- pyspark.sql.functions.pandas_udf """ from pyspark.sql import DataFrame from pyspark.sql.pandas.functions import pandas_udf
assert isinstance(self, DataFrame)
udf = pandas_udf( func, returnType=schema, functionType=PythonEvalType.SQL_MAP_PANDAS_ITER_UDF) udf_column = udf(*[self[col] for col in self.columns]) jdf = self._jdf.mapInPandas(udf_column._jc.expr()) return DataFrame(jdf, self.sql_ctx)
.master("local[4]")\ .appName("sql.pandas.map_ops tests")\ .getOrCreate() pyspark.sql.pandas.map_ops, globs=globs, optionflags=doctest.ELLIPSIS | doctest.NORMALIZE_WHITESPACE | doctest.REPORT_NDIFF) sys.exit(-1)
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