# 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. from pandas import DataFrame from superset.constants import PandasAxis from superset.utils.pandas_postprocessing.utils import ( _append_columns, validate_column_args, ) @validate_column_args("columns") def diff( df: DataFrame, columns: dict[str, str], periods: int = 1, axis: PandasAxis = PandasAxis.ROW, ) -> DataFrame: """ Calculate row-by-row or column-by-column difference for select columns. :param df: DataFrame on which the diff will be based. :param columns: columns on which to perform diff, mapping source column to target column. For instance, `{'y': 'y'}` will replace the column `y` with the diff value in `y`, while `{'y': 'y2'}` will add a column `y2` based on diff values calculated from `y`, leaving the original column `y` unchanged. :param periods: periods to shift for calculating difference. :param axis: 0 for row, 1 for column. default 0. :return: DataFrame with diffed columns :raises InvalidPostProcessingError: If the request in incorrect """ df_diff = df[columns.keys()] df_diff = df_diff.diff(periods=periods, axis=axis) return _append_columns(df, df_diff, columns)