Example #1
0
    def test__parabolic_crossentropy(self):
        """when"""
        categories = 11
        loss_function = parabolic_crossentropy(categories, 1)
        """then"""
        for truth in range(categories):
            losses = []
            for prediction in range(categories):
                loss = K.eval(
                    loss_function(K.variable(one_hot(truth, categories)),
                                  K.variable(one_hot(prediction, categories))))
                losses.append(loss)

            # all predictions left of truth need to increase
            for i in range(1, truth):
                self.assertGreater(losses[i - 1], losses[i])

            # right of truth need to decrease
            for i in range(truth, categories - 1):
                self.assertLess(losses[i], losses[i + 1])

            if truth > 0 and truth < categories - 1:
                if truth > categories / 2:
                    # right tail:
                    self.assertGreater(losses[truth - 1], losses[truth + 1])
                else:
                    # left tail
                    self.assertGreater(losses[truth + 1], losses[truth - 1])
Example #2
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 def test__tailed_categorical_crossentropy(self):
     """when"""
     categories = 11
     loss = tailed_categorical_crossentropy(categories, 1)
     """then"""
     l = K.eval(loss(K.variable(one_hot(3, 11)), K.variable(one_hot(6,
                                                                    11))))
     pickle
     """then"""
     self.assertGreater(l, 0)
     save_object(loss, '/tmp/test__tailed_categorical_crossentropy.dill')
Example #3
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def ta_one_hot_categories(df: _pd.DataFrame):
    """
    Take a category column or a column of integers and turn them into a one hot encoded data frame
    :param df: a series or a data frame which has category columns or integer columns
    :return: a multi index data frame with one hot encoded integer columns
             note: can be empty
    """

    df = df.to_frame() if isinstance(df, _pd.Series) else df
    res = None

    for col in df.columns:
        if hasattr(df[col], "cat"):
            categories = [str(cat) for cat in df[col].cat.categories]
            df_of_categories = index_of_categories(df[col])

        elif df[col].dtype.kind in 'iu':
            categories = sorted(set(df[col].values))
            df_of_categories = df

        else:
            continue

        number_of_categories = len(categories)
        ohdf = df_of_categories[[col]].apply(lambda r: util.one_hot(r, number_of_categories), axis=1, result_type='expand')
        ohdf.columns = _pd.MultiIndex.from_product([[col], categories])
        res = ohdf if res is None else res.join(ohdf)

    if res is None:
        _log.warning(f'non of the {df.columns} are of type category index or integer value!\n'
                     f'You might want to call df.ta_one_hot_categories(df.ta_bucketize(3))')

    return res
Example #4
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 def test__differentiable_argmax(self):
     """given"""
     args = 10
     argmax = DifferentiableArgmax(args)
     """when"""
     res = np.array([
         K.eval(argmax(K.variable(one_hot(i, args)))) for i in range(args)
     ])
     """then"""
     print(res)
     np.testing.assert_array_almost_equal(res, np.arange(0, args))
Example #5
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 def convoluted(df: _pd.Series) -> _np.ndarray:
     min = df.min()
     max = df.max()
     interval_index = _np.linspace(min, max, buckets)
     indexes = _np.digitize(df, interval_index) - 1
     _np.array([util.one_hot(index, buckets) for index in indexes])
Example #6
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    def test_normal_penalized_crossentropy(self):
        """when"""
        loss = normal_penalized_crossentropy(11)
        """then"""
        for i in range(11):
            self.assertLess(
                K.eval(
                    loss(K.variable(one_hot(i, 11)),
                         K.variable(one_hot(i, 11)))), 0.00001)

        self.assertLess(
            K.eval(loss(K.variable(one_hot(7, 11)), K.variable(one_hot(8,
                                                                       11)))),
            K.eval(loss(K.variable(one_hot(7, 11)), K.variable(one_hot(6,
                                                                       11)))))

        self.assertLess(
            K.eval(loss(K.variable(one_hot(6, 11)), K.variable(one_hot(7,
                                                                       11)))),
            K.eval(loss(K.variable(one_hot(6, 11)), K.variable(one_hot(5,
                                                                       11)))))

        self.assertLess(
            K.eval(loss(K.variable(one_hot(3, 11)), K.variable(one_hot(2,
                                                                       11)))),
            K.eval(loss(K.variable(one_hot(3, 11)), K.variable(one_hot(4,
                                                                       11)))))