init reader.h and reader.cc files

paddle/framework/reader.cc

+//   Copyright (c) 2018 PaddlePaddle Authors. All Rights Reserved.
+//
+// Licensed 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.
+
+#include "paddle/framework/reader.h"
+
+namespace paddle {
+namespace framework {
+
+DDim Reader::shape(int idx) const {
+  PADDLE_ENFORCE_LT(
+      idx, shapes_.size(),
+      "Cannot get the %d'th shape, 'shapes_' only has %d elements.", idx,
+      shapes_.size());
+}
+
+int RandomReader::ReadNext(std::vector<LoDTensor>* outs) {
+  PADDLE_ENFORCE_EQ(
+      shapes_.size(), outs.size(),
+      "shapes_.size() is %d, while outs.size() is %d. They are not equal.",
+      shapes_.size(), outs.size());
+  std::minstd_rand engine;
+  unsigned int seed = std::random_device()();
+  engine.seed(seed);
+  std::uniform_real_distribution<float> dist(min_, max_);
+  for (int idx = 0; idx < shapes_.size(); ++idx) {
+    DDim shape = shapes_[idx];
+    LoDTensor* out = outs[idx];
+    int64_t numel = out->numel();
+    PADDLE_ENFORCE_EQ(product(shape), numel,
+                      "The product of %d'th shape is %lld, while the "
+                      "corresponding out's numel is %lld. They are not equal.",
+                      idx, product(shape), numel);
+    for (int64_t i = 0; i < numel, ++i) {
+      out[i] = dist(engine);
+    }
+  }
+  return 0;
+}
+}  // namespace framework
+}  // namespace paddle

paddle/framework/reader.h

+//   Copyright (c) 2018 PaddlePaddle Authors. All Rights Reserved.
+//
+// Licensed 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.
+
+#pragma once
+
+#include "paddle/framework/ddim.h"
+#include "paddle/framework/lod_tensor.h"
+
+namespace paddle {
+namespace framework {
+
+class Reader {
+ public:
+  virtual int ReadNext(std::vector<LoDTensor>* outs) = 0;
+  DDim shape(int idx) const;
+
+ private:
+  std::vector<DDim> shapes_;
+};
+
+// file readers
+
+class RandomReader : public Reader {
+ public:
+  RandomReader(const std::vector<DDim>& shapes, float min, float max)
+      : shapes_(shapes), min_(min), max_(max) {}
+  int ReadNext(std::vector<LoDTensor>* outs) override;
+
+ private:
+  float min_;
+  float max_;
+};
+
+// decorators
+
+class BatchReader : public Reader {
+ public:
+  BatchReader(const Reader* reader) : reader_(reader) {}
+  int ReadNext(std::vector<LoDTensor>* outs) override;
+
+ private:
+  const Reader* reader_;
+};
+
+class ShuffleReader : public Reader {
+ public:
+  ShuffleReader(const Reader* reader) : reader_(reader) {}
+  int ReadNext(std::vector<LoDTensor>* outs) override;
+
+ private:
+  const Reader* reader_;
+};
+}  // namespace framework
+}  // namespace paddle