Merge pull request #3815 from xinghai-sun/cos_sim_layer2

Add cosine similarity operator.

paddle/operators/cos_sim_op.cc

+/* Copyright (c) 2016 PaddlePaddle Authors. All Rights Reserve.
+
+   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/operators/cos_sim_op.h"
+
+namespace paddle {
+namespace operators {
+
+using framework::Tensor;
+
+class CosSimOp : public framework::OperatorWithKernel {
+ public:
+  using framework::OperatorWithKernel::OperatorWithKernel;
+
+ protected:
+  void InferShape(const framework::InferShapeContext &ctx) const override {
+    PADDLE_ENFORCE_NOT_NULL(ctx.InputVar("X"), "Input(X) must not be null.");
+    PADDLE_ENFORCE_NOT_NULL(ctx.InputVar("Y"), "Input(Y) must not be null.");
+    PADDLE_ENFORCE_EQ(ctx.Input<Tensor>("X")->dims(),
+                      ctx.Input<Tensor>("Y")->dims(),
+                      "Dimensions of Input(X) and Input(Y) must be the same.");
+
+    auto dims = ctx.Input<Tensor>("X")->dims();
+    ctx.Output<Tensor>("Out")->Resize({dims[0], 1});
+    ctx.Output<Tensor>("XNorm")->Resize({dims[0], 1});
+    ctx.Output<Tensor>("YNorm")->Resize({dims[0], 1});
+  }
+};
+
+class CosSimOpMaker : public framework::OpProtoAndCheckerMaker {
+ public:
+  CosSimOpMaker(framework::OpProto *proto, framework::OpAttrChecker *op_checker)
+      : OpProtoAndCheckerMaker(proto, op_checker) {
+    AddInput("X", "The first input of cos_sim op.");
+    AddInput("Y", "The second input of cos_sim op.");
+    AddOutput("Out", "The output of cos_sim op.");
+    AddOutput("XNorm", "Row norm of the first input.").AsIntermediate();
+    AddOutput("YNorm", "Row norm of the second input.").AsIntermediate();
+
+    AddComment(R"DOC(
+Cosine Similarity Operator.
+
+The equation is: Out = X^T * Y / (sqrt(X^T * X) * sqrt(Y^T * Y))
+)DOC");
+  }
+};
+
+class CosSimOpGrad : public framework::OperatorWithKernel {
+ public:
+  using framework::OperatorWithKernel::OperatorWithKernel;
+
+ protected:
+  void InferShape(const framework::InferShapeContext &ctx) const override {
+    PADDLE_ENFORCE_NOT_NULL(ctx.InputVar("X"), "Input(X) must not be null.");
+    PADDLE_ENFORCE_NOT_NULL(ctx.InputVar("Y"), "Input(Y) must not be null.");
+    PADDLE_ENFORCE_NOT_NULL(ctx.InputVar("XNorm"),
+                            "Input(XNorm) must not be null.");
+    PADDLE_ENFORCE_NOT_NULL(ctx.InputVar("YNorm"),
+                            "Input(YNorm) must not be null.");
+    PADDLE_ENFORCE_NOT_NULL(ctx.InputVar(framework::GradVarName("Out")),
+                            "Input(Out@GRAD) must not be null.");
+
+    auto x_dims = ctx.Input<Tensor>("X")->dims();
+    auto y_dims = ctx.Input<Tensor>("Y")->dims();
+    auto xnorm_dims = ctx.Input<Tensor>("XNorm")->dims();
+    auto ynorm_dims = ctx.Input<Tensor>("YNorm")->dims();
+    auto out_dims = ctx.Input<Tensor>(framework::GradVarName("Out"))->dims();
+    PADDLE_ENFORCE_EQ(x_dims, y_dims,
+                      "Dimensions of Input(X) and Input(Y) must be the same.");
+    PADDLE_ENFORCE_EQ(xnorm_dims[0], x_dims[0],
+                      "1st dimension of XNorm must equal that of Input(X).");
+    PADDLE_ENFORCE_EQ(xnorm_dims[1], 1, "2st dimension of XNorm must be one.");
+    PADDLE_ENFORCE_EQ(ynorm_dims[0], y_dims[0],
+                      "1st dimension of YNorm must equal that of Input(Y).");
+    PADDLE_ENFORCE_EQ(ynorm_dims[1], 1, "2st dimension of YNorm must be one.");
+    PADDLE_ENFORCE_EQ(out_dims[0], x_dims[0],
+                      "1st dimension of Out@GRAD must equal that of Input(X)");
+    PADDLE_ENFORCE_EQ(out_dims[1], 1, "1st dimension of Out@GRAD must be one.");
+
+    auto *x_grad = ctx.Output<Tensor>(framework::GradVarName("X"));
+    auto *y_grad = ctx.Output<Tensor>(framework::GradVarName("Y"));
+    if (x_grad) x_grad->Resize(x_dims);
+    if (y_grad) y_grad->Resize(y_dims);
+  }
+};
+
+}  // namespace operators
+}  // namespace paddle
+
+namespace ops = paddle::operators;
+REGISTER_OP(cos_sim, ops::CosSimOp, ops::CosSimOpMaker, cos_sim_grad,
+            ops::CosSimOpGrad);
+REGISTER_OP_CPU_KERNEL(cos_sim,
+                       ops::CosSimKernel<paddle::platform::CPUPlace, float>);
+REGISTER_OP_CPU_KERNEL(
+    cos_sim_grad, ops::CosSimGradKernel<paddle::platform::CPUPlace, float>);

paddle/operators/cos_sim_op.cu

+/* Copyright (c) 2016 PaddlePaddle Authors. All Rights Reserve.
+
+   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. */
+
+#define EIGEN_USE_GPU
+#include "paddle/operators/cos_sim_op.h"
+
+namespace ops = paddle::operators;
+REGISTER_OP_GPU_KERNEL(cos_sim,
+                       ops::CosSimKernel<paddle::platform::GPUPlace, float>);
+REGISTER_OP_GPU_KERNEL(
+    cos_sim_grad, ops::CosSimGradKernel<paddle::platform::GPUPlace, float>);

paddle/operators/cos_sim_op.h

+/* Copyright (c) 2016 PaddlePaddle Authors. All Rights Reserve.
+
+   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/eigen.h"
+#include "paddle/framework/op_registry.h"
+
+namespace paddle {
+namespace operators {
+
+using Tensor = framework::Tensor;
+template <typename T, int MajorType = Eigen::RowMajor,
+          typename IndexType = Eigen::DenseIndex>
+using EigenMatrix = framework::EigenMatrix<T, MajorType, IndexType>;
+
+template <typename Place, typename T>
+class CosSimKernel : public framework::OpKernel {
+ public:
+  void Compute(const framework::ExecutionContext& context) const override {
+    auto* input_x = context.Input<Tensor>("X");
+    auto* input_y = context.Input<Tensor>("Y");
+    auto* output_z = context.Output<Tensor>("Out");
+    auto* output_x_norm = context.Output<Tensor>("XNorm");
+    auto* output_y_norm = context.Output<Tensor>("YNorm");
+
+    output_z->mutable_data<T>(context.GetPlace());
+    output_x_norm->mutable_data<T>(context.GetPlace());
+    output_y_norm->mutable_data<T>(context.GetPlace());
+
+    auto dims = input_x->dims();
+    int size = static_cast<int>(framework::product(dims));
+    auto new_dims = framework::make_ddim({dims[0], size / dims[0]});
+    auto x = EigenMatrix<T>::From(*input_x, new_dims);
+    auto y = EigenMatrix<T>::From(*input_y, new_dims);
+    auto z = EigenMatrix<T>::From(*output_z);
+    auto x_norm = EigenMatrix<T>::From(*output_x_norm);
+    auto y_norm = EigenMatrix<T>::From(*output_y_norm);
+
+    auto place = context.GetEigenDevice<Place>();
+    auto xy = (x * y).sum(Eigen::array<int, 1>({1}));
+    x_norm.device(place) = x.square().sum(Eigen::array<int, 1>({1})).sqrt();
+    y_norm.device(place) = y.square().sum(Eigen::array<int, 1>({1})).sqrt();
+    z.device(place) = xy / x_norm / y_norm;
+  }
+};
+
+template <typename Place, typename T>
+class CosSimGradKernel : public framework::OpKernel {
+ public:
+  void Compute(const framework::ExecutionContext& context) const override {
+    auto* input_x = context.Input<Tensor>("X");
+    auto* input_y = context.Input<Tensor>("Y");
+    auto* input_z = context.Input<Tensor>("Out");
+    auto* input_x_norm = context.Input<Tensor>("XNorm");
+    auto* input_y_norm = context.Input<Tensor>("YNorm");
+    auto* output_grad_x = context.Output<Tensor>(framework::GradVarName("X"));
+    auto* output_grad_y = context.Output<Tensor>(framework::GradVarName("Y"));
+    auto* input_grad_z = context.Input<Tensor>(framework::GradVarName("Out"));
+
+    auto dims = input_x->dims();
+    int size = static_cast<int>(framework::product(dims));
+    auto new_dims = framework::make_ddim({dims[0], size / dims[0]});
+    auto x = EigenMatrix<T>::From(*input_x, new_dims);
+    auto y = EigenMatrix<T>::From(*input_y, new_dims);
+    auto z = EigenMatrix<T>::From(*input_z);
+    auto x_norm = EigenMatrix<T>::From(*input_x_norm);
+    auto y_norm = EigenMatrix<T>::From(*input_y_norm);
+    auto dz = EigenMatrix<T>::From(*input_grad_z);
+
+    Eigen::DSizes<int, 2> bcast(1, new_dims[1]);
+    auto z_bcast = z.broadcast(bcast);
+    auto dz_bcast = dz.broadcast(bcast);
+    auto place = context.GetEigenDevice<Place>();
+    auto x_snorm_bcast = x_norm.square().eval().broadcast(bcast);
+    auto y_snorm_bcast = y_norm.square().eval().broadcast(bcast);
+    auto norm_prod_bcast = (x_norm * y_norm).eval().broadcast(bcast);
+    if (output_grad_x) {
+      output_grad_x->mutable_data<T>(context.GetPlace());
+      auto dx = EigenMatrix<T>::From(*output_grad_x, new_dims);
+      dx.device(place) =
+          dz_bcast * (y / norm_prod_bcast - z_bcast * x / x_snorm_bcast);
+    }
+    if (output_grad_y) {
+      output_grad_y->mutable_data<T>(context.GetPlace());
+      auto dy = EigenMatrix<T>::From(*output_grad_y, new_dims);
+      dy.device(place) =
+          dz_bcast * (x / norm_prod_bcast - z_bcast * y / y_snorm_bcast);
+    }
+  }
+};
+
+}  // namespace operators
+}  // namespace paddle

paddle/pybind/pybind.cc

@@ -46,6 +46,7 @@ USE_OP(lookup_table);
 USE_OP(scale);
 USE_NO_KERNEL_OP(identity);
 USE_OP(minus);
+USE_OP(cos_sim);
 USE_CPU_ONLY_OP(gather);
 USE_CPU_ONLY_OP(scatter);
 

python/paddle/v2/framework/tests/CMakeLists.txt

@@ -4,6 +4,7 @@ py_test(test_scope SRCS test_scope.py)
 
 py_test(test_tensor SRCS test_tensor.py)
 py_test(test_mul_op SRCS test_mul_op.py)
+py_test(test_cos_sim_op SRCS test_cos_sim_op.py)
 
 py_test(test_mean_op SRCS test_mean_op.py)
 

python/paddle/v2/framework/tests/test_cos_sim_op.py

+import unittest
+import numpy as np
+from gradient_checker import GradientChecker, create_op
+from op_test_util import OpTestMeta
+
+
+class TestCosSimOp(unittest.TestCase):
+    __metaclass__ = OpTestMeta
+
+    def setUp(self):
+        self.type = "cos_sim"
+        self.inputs = {
+            'X': np.random.random((32, 64)).astype("float32"),
+            'Y': np.random.random((32, 64)).astype("float32")
+        }
+        expect_x_norm = np.linalg.norm(self.inputs['X'], axis=1)
+        expect_y_norm = np.linalg.norm(self.inputs['Y'], axis=1)
+        expect_out = (self.inputs['X'] * self.inputs['Y']).sum(axis=1) / \
+            expect_x_norm / expect_y_norm
+        self.outputs = {
+            'XNorm': np.expand_dims(expect_x_norm, 1),
+            'YNorm': np.expand_dims(expect_y_norm, 1),
+            'Out': np.expand_dims(expect_out, 1)
+        }
+
+
+class TestCosSimGradOp(GradientChecker):
+    def setUp(self):
+        self.op = create_op("cos_sim")
+        self.inputs = {
+            'X': np.random.random((10, 5)).astype("float32"),
+            'Y': np.random.random((10, 5)).astype("float32")
+        }
+
+    def test_cpu_gpu_compare(self):
+        self.compare_grad(self.op, self.inputs)
+
+    def test_normal(self):
+        self.check_grad(
+            self.op, self.inputs, ["X", "Y"], "Out", max_relative_error=0.05)
+
+    def test_ignore_x(self):
+        self.check_grad(
+            self.op,
+            self.inputs, ["Y"],
+            "Out",
+            max_relative_error=0.05,
+            no_grad_set={"X"})
+
+    def test_ignore_y(self):
+        self.check_grad(
+            self.op,
+            self.inputs, ["X"],
+            "Out",
+            max_relative_error=0.05,
+            no_grad_set={"Y"})
+
+
+if __name__ == '__main__':
+    unittest.main()