1 /**
2 * Copyright 2019 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 #include "minddata/dataset/engine/datasetops/source/sampler/subset_random_sampler.h"
17
18 #include <algorithm>
19 #include <random>
20 #include <string>
21
22 #include "minddata/dataset/core/global_context.h"
23 #include "minddata/dataset/util/random.h"
24
25 namespace mindspore {
26 namespace dataset {
27 // Constructor.
SubsetRandomSamplerRT(const std::vector<int64_t> & indices,int64_t num_samples,int64_t samples_per_tensor)28 SubsetRandomSamplerRT::SubsetRandomSamplerRT(const std::vector<int64_t> &indices, int64_t num_samples,
29 int64_t samples_per_tensor)
30 : SubsetSamplerRT(indices, num_samples, samples_per_tensor) {}
31
32 // Initialized this Sampler.
InitSampler()33 Status SubsetRandomSamplerRT::InitSampler() {
34 if (is_initialized) {
35 return Status::OK();
36 }
37
38 // Initialize random generator with seed from config manager
39 rand_gen_.seed(GetSeed());
40
41 // num_samples_ could be smaller than the total number of input id's.
42 // We will shuffle the full set of id's, but only select the first num_samples_ of them later.
43 std::shuffle(indices_.begin(), indices_.end(), rand_gen_);
44
45 return SubsetSamplerRT::InitSampler();
46 }
47
48 // Reset the internal variable to the initial state.
ResetSampler()49 Status SubsetRandomSamplerRT::ResetSampler() {
50 // Randomized the indices again.
51 rand_gen_.seed(GetSeed());
52 std::shuffle(indices_.begin(), indices_.end(), rand_gen_);
53
54 return SubsetSamplerRT::ResetSampler();
55 }
56
SamplerPrint(std::ostream & out,bool show_all) const57 void SubsetRandomSamplerRT::SamplerPrint(std::ostream &out, bool show_all) const {
58 out << "\nSampler: SubsetRandomSampler";
59 if (show_all) {
60 // Call the super class for displaying any common detailed info
61 SamplerRT::SamplerPrint(out, show_all);
62 // Then add our own info if any
63 }
64 }
65
to_json(nlohmann::json * out_json)66 Status SubsetRandomSamplerRT::to_json(nlohmann::json *out_json) {
67 nlohmann::json args;
68 RETURN_IF_NOT_OK(SubsetSamplerRT::to_json(&args));
69 args["sampler_name"] = "SubsetRandomSampler";
70 return Status::OK();
71 }
72 } // namespace dataset
73 } // namespace mindspore
74