1 /** 2 * Copyright 2020 Huawei Technologies Co., Ltd 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 #ifndef MINDSPORE_CCSRC_MINDDATA_DATASET_CORE_TENSOR_HELPERS_H_ 17 #define MINDSPORE_CCSRC_MINDDATA_DATASET_CORE_TENSOR_HELPERS_H_ 18 19 #include <memory> 20 #include <vector> 21 22 #include "minddata/dataset/include/dataset/transforms.h" 23 #include "minddata/dataset/include/dataset/constants.h" 24 25 namespace mindspore { 26 namespace dataset { 27 /// Recursive helper function to generate indices based on vector of SliceOptions. It recursively iterates through each 28 /// range represented by slice_options to generate a list of indices to be sliced. 29 /// \param[out] matrix Generated nested vector of indices 30 /// Example: For a 4 x 2 tensor, and with slice_list = {SliceOption({0})} (the first row), matrix will become 31 /// {{0}}. For slice_list = {SliceOption(all), SliceOption({0})} (the first column), matrix will become 32 /// {{0, 0}, {1, 0}, {2, 0}, {3, 0}}. 33 /// For slice_list = {SliceOption({0, 2})}, matrix will become {{0}, {2}}. The size of each nested array is always 34 /// equal to (slice_list).size(). 35 /// \param[in] depth used to keep track of recursion level 36 /// \param[in] numbers vector used to represent current index 37 /// \param[in] matrix 2D vector to be populated with desired indices 38 /// \param[in] slice_options vector of SliceOption objects 39 void IndexGeneratorHelper(int8_t depth, std::vector<dsize_t> *numbers, const std::vector<SliceOption> &slice_list, 40 std::vector<std::vector<dsize_t>> *matrix); 41 42 /// Generate indices based on vector of SliceOptions 43 /// Calls the recursive helper function IndexGeneratorHelper 44 /// \param[in] slice_list vector of SliceOption objects. Note: If the user passes 45 /// {SliceOption(true), SliceOption(true)}, it will return a M x 2 vector, instead of reducing it to 46 /// {SliceOption(true)} first to only generate a M x 1 vector. 47 /// \return std::vector<std::vector<dsize_t>> 2D vector of generated indices, M x (slice_list).size() 48 std::vector<std::vector<dsize_t>> IndexGenerator(const std::vector<SliceOption> &slice_list); 49 } // namespace dataset 50 } // namespace mindspore 51 #endif // MINDSPORE_CCSRC_MINDDATA_DATASET_CORE_TENSOR_HELPERS_H_ 52