#
# Copyright 2013 Quantopian, 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.

import math


def tolerant_equals(a, b, atol=10e-7, rtol=10e-7):
    return math.fabs(a - b) <= (atol + rtol * math.fabs(b))


try:
    # fast versions
    import bottleneck as bn
    nanmean = bn.nanmean
    nanstd = bn.nanstd
    nansum = bn.nansum
    nanmax = bn.nanmax
    nanmin = bn.nanmin
    nanargmax = bn.nanargmax
    nanargmin = bn.nanargmin
except ImportError:
    # slower numpy
    import numpy as np
    nanmean = np.nanmean
    nanstd = np.nanstd
    nansum = np.nansum
    nanmax = np.nanmax
    nanmin = np.nanmin
    nanargmax = np.nanargmax
    nanargmin = np.nanargmin