# Copyright (c) 2016-present, Facebook, Inc.
#
# 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.
##############################################################################

from __future__ import absolute_import
from __future__ import division
from __future__ import print_function
from __future__ import unicode_literals

from caffe2.python import core
from hypothesis import given
import caffe2.python.hypothesis_test_util as hu
import numpy as np

import unittest


class TestRelu(hu.HypothesisTestCase):

    @given(X=hu.tensor(),
           **hu.gcs)
    def test_relu_n(self, X, gc, dc):
        X = 0.8 * np.sign(X)
        X = X - 0.5
        X[X == 0.0] = 0.01
        n = max(np.max(X), 1.0) / 2
        X[X == 0.2] = 0.01

        def relu_n_ref(X):
            Y = np.minimum(np.maximum(X, 0), n)
            return [Y]

        op = core.CreateOperator("ReluN", ["X"], ["Y"], n=n)
        self.assertReferenceChecks(gc, op, [X], relu_n_ref)
        self.assertDeviceChecks(dc, op, [X], [0])
        self.assertGradientChecks(gc, op, [X], 0, [0], stepsize=0.001, threshold=0.001)


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