test_regularizer_api.py

#   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.

import unittest
from functools import partial
import contextlib
import numpy as np
import random
import paddle
import paddle.fluid.core as core
import paddle.fluid as fluid


def bow_net(data,
            label,
            dict_dim,
            is_sparse=False,
            emb_dim=8,
            hid_dim=8,
            hid_dim2=6,
            class_dim=2):
    """
    BOW net
    This model is from https://github.com/PaddlePaddle/models:
    fluid/PaddleNLP/text_classification/nets.py
    """
    emb = fluid.layers.embedding(input=data,
                                 is_sparse=is_sparse,
                                 size=[dict_dim, emb_dim])
    bow = fluid.layers.sequence_pool(input=emb, pool_type='sum')
    bow_tanh = fluid.layers.tanh(bow)
    fc_1 = fluid.layers.fc(input=bow_tanh, size=hid_dim, act="tanh")
    fc_2 = fluid.layers.fc(input=fc_1, size=hid_dim2, act="tanh")
    prediction = fluid.layers.fc(input=[fc_2], size=class_dim, act="softmax")
    cost = fluid.layers.cross_entropy(input=prediction, label=label)
    avg_cost = paddle.mean(x=cost)

    return avg_cost


class TestRegularizer(unittest.TestCase):

    def setUp(self):
        self.word_len = 1500
        self.train_data = [[(random.sample(range(1000), 10), [0])]
                           for _ in range(2)]

    def get_places(self):
        places = [core.CPUPlace()]
        if core.is_compiled_with_cuda():
            places.append(core.CUDAPlace(0))
        return places

    @contextlib.contextmanager
    def scope_prog_guard(self, main_prog, startup_prog):
        scope = fluid.core.Scope()
        with fluid.unique_name.guard():
            with fluid.scope_guard(scope):
                with fluid.program_guard(main_prog, startup_prog):
                    yield

    def run_program(self, place, feed_list):
        exe = fluid.Executor(place)
        feeder = fluid.DataFeeder(feed_list=feed_list, place=place)
        exe.run(fluid.default_startup_program())

        main_prog = fluid.default_main_program()
        param_list = [var.name for var in main_prog.block(0).all_parameters()]

        param_sum = []
        for data in self.train_data:
            out = exe.run(main_prog,
                          feed=feeder.feed(data),
                          fetch_list=param_list)
            p_sum = 0
            for v in out:
                p_sum += np.sum(np.abs(v))
            param_sum.append(p_sum)
        return param_sum

    def check_l2decay_regularizer(self, place, model):
        paddle.seed(1)
        paddle.framework.random._manual_program_seed(1)
        main_prog = fluid.framework.Program()
        startup_prog = fluid.framework.Program()
        with self.scope_prog_guard(main_prog=main_prog,
                                   startup_prog=startup_prog):
            data = fluid.layers.data(name="words",
                                     shape=[1],
                                     dtype="int64",
                                     lod_level=1)
            label = fluid.layers.data(name="label", shape=[1], dtype="int64")

            avg_cost = model(data, label, self.word_len)

            optimizer = fluid.optimizer.Adagrad(
                learning_rate=0.1,
                regularization=paddle.regularizer.L2Decay(1.0))
            optimizer.minimize(avg_cost)
            param_sum = self.run_program(place, [data, label])
        return param_sum

    def check_l2decay(self, place, model):
        paddle.seed(1)
        paddle.framework.random._manual_program_seed(1)
        main_prog = fluid.framework.Program()
        startup_prog = fluid.framework.Program()

        with self.scope_prog_guard(main_prog=main_prog,
                                   startup_prog=startup_prog):
            data = fluid.layers.data(name="words",
                                     shape=[1],
                                     dtype="int64",
                                     lod_level=1)
            label = fluid.layers.data(name="label", shape=[1], dtype="int64")

            avg_cost_l2 = model(data, label, self.word_len)

            param_list = fluid.default_main_program().block(0).all_parameters()
            para_sum = []
            for para in param_list:
                para_mul = fluid.layers.square(x=para)
                para_sum.append(fluid.layers.reduce_sum(input=para_mul))
            avg_cost_l2 += fluid.layers.sums(para_sum) * .5

            optimizer = fluid.optimizer.Adagrad(learning_rate=0.1)
            optimizer.minimize(avg_cost_l2)
            param_sum = self.run_program(place, [data, label])
        return param_sum

    def test_l2(self):
        paddle.enable_static()
        for place in self.get_places():
            dense_sparse_p_sum = []
            for sparse in [True, False]:
                model = partial(bow_net, is_sparse=sparse)
                framework_l2 = self.check_l2decay_regularizer(place, model)
                l2 = self.check_l2decay(place, model)
                assert len(l2) == len(framework_l2)
                for i in range(len(l2)):
                    assert np.isclose(a=framework_l2[i], b=l2[i], rtol=5e-5)
                dense_sparse_p_sum.append(framework_l2)

            assert len(dense_sparse_p_sum[0]) == len(dense_sparse_p_sum[1])
            for i in range(len(dense_sparse_p_sum[0])):
                assert np.isclose(a=dense_sparse_p_sum[0][i],
                                  b=dense_sparse_p_sum[1][i],
                                  rtol=5e-5)

    def test_repeated_regularization(self):
        paddle.enable_static()
        l1 = paddle.regularizer.L1Decay(0.1)
        l2 = paddle.regularizer.L2Decay(0.01)
        fc_param_attr = fluid.ParamAttr(regularizer=l1)
        with fluid.program_guard(fluid.Program(), fluid.Program()):
            x = fluid.layers.uniform_random([2, 2, 3])
            out = fluid.layers.fc(x, 5, param_attr=fc_param_attr)
            loss = fluid.layers.reduce_sum(out)
            sgd = fluid.optimizer.SGD(learning_rate=0.1, regularization=l2)
            sgd.minimize(loss)
        with fluid.dygraph.guard():
            input = fluid.dygraph.to_variable(
                np.random.randn(3, 2).astype('float32'))
            paddle.seed(1)
            paddle.framework.random._manual_program_seed(1)

            linear1 = fluid.dygraph.Linear(2,
                                           2,
                                           param_attr=fc_param_attr,
                                           bias_attr=fc_param_attr)
            linear2 = fluid.dygraph.Linear(2,
                                           2,
                                           param_attr=fc_param_attr,
                                           bias_attr=fc_param_attr)

            loss1 = linear1(input)
            loss1.backward()
            # set l2 regularizer in optimizer, but l1 in fluid.ParamAttr

            fluid.optimizer.SGD(parameter_list=linear1.parameters(),
                                learning_rate=1e-2,
                                regularization=l2).minimize(loss1)
            # only set l1 in fluid.ParamAttr
            loss2 = linear2(input)
            loss2.backward()
            fluid.optimizer.SGD(parameter_list=linear2.parameters(),
                                learning_rate=1e-2).minimize(loss2)
            # they should both be applied by l1, and keep the same
            np.testing.assert_allclose(
                linear1.weight.numpy(),
                linear2.weight.numpy(),
                rtol=1e-05,
                err_msg=
                'weight should use the regularization in fluid.ParamAttr!')
            np.testing.assert_allclose(
                linear1.bias.numpy(),
                linear2.bias.numpy(),
                rtol=1e-05,
                err_msg='bias should use the regularization in fluid.ParamAttr!'
            )


if __name__ == '__main__':
    unittest.main()