Ejemplo n.º 1
0
    def reindex(self, target, method=None, level=None, limit=None,
                tolerance=None):
        """
        Create index with target's values (move/add/delete values as necessary)

        Returns
        -------
        new_index : pd.Index
            Resulting index
        indexer : np.ndarray or None
            Indices of output values in original index

        """

        if method is not None:
            raise NotImplementedError("argument method is not implemented for "
                                      "CategoricalIndex.reindex")
        if level is not None:
            raise NotImplementedError("argument level is not implemented for "
                                      "CategoricalIndex.reindex")
        if limit is not None:
            raise NotImplementedError("argument limit is not implemented for "
                                      "CategoricalIndex.reindex")

        target = ibase._ensure_index(target)

        if not is_categorical_dtype(target) and not target.is_unique:
            raise ValueError("cannot reindex with a non-unique indexer")

        indexer, missing = self.get_indexer_non_unique(np.array(target))
        new_target = self.take(indexer)

        # filling in missing if needed
        if len(missing):
            cats = self.categories.get_indexer(target)

            if (cats == -1).any():
                # coerce to a regular index here!
                result = Index(np.array(self), name=self.name)
                new_target, indexer, _ = result._reindex_non_unique(
                    np.array(target))

            else:

                codes = new_target.codes.copy()
                codes[indexer == -1] = cats[missing]
                new_target = self._create_from_codes(codes)

        # we always want to return an Index type here
        # to be consistent with .reindex for other index types (e.g. they don't
        # coerce based on the actual values, only on the dtype)
        # unless we had an inital Categorical to begin with
        # in which case we are going to conform to the passed Categorical
        new_target = np.asarray(new_target)
        if is_categorical_dtype(target):
            new_target = target._shallow_copy(new_target, name=self.name)
        else:
            new_target = Index(new_target, name=self.name)

        return new_target, indexer
Ejemplo n.º 2
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    def reindex(self, target, method=None, level=None, limit=None,
                tolerance=None):
        """
        Create index with target's values (move/add/delete values as necessary)

        Returns
        -------
        new_index : pd.Index
            Resulting index
        indexer : np.ndarray or None
            Indices of output values in original index

        """

        if method is not None:
            raise NotImplementedError("argument method is not implemented for "
                                      "CategoricalIndex.reindex")
        if level is not None:
            raise NotImplementedError("argument level is not implemented for "
                                      "CategoricalIndex.reindex")
        if limit is not None:
            raise NotImplementedError("argument limit is not implemented for "
                                      "CategoricalIndex.reindex")

        target = ibase._ensure_index(target)

        if not is_categorical_dtype(target) and not target.is_unique:
            raise ValueError("cannot reindex with a non-unique indexer")

        indexer, missing = self.get_indexer_non_unique(np.array(target))
        new_target = self.take(indexer)

        # filling in missing if needed
        if len(missing):
            cats = self.categories.get_indexer(target)

            if (cats == -1).any():
                # coerce to a regular index here!
                result = Index(np.array(self), name=self.name)
                new_target, indexer, _ = result._reindex_non_unique(
                    np.array(target))

            else:

                codes = new_target.codes.copy()
                codes[indexer == -1] = cats[missing]
                new_target = self._create_from_codes(codes)

        # we always want to return an Index type here
        # to be consistent with .reindex for other index types (e.g. they don't
        # coerce based on the actual values, only on the dtype)
        # unless we had an inital Categorical to begin with
        # in which case we are going to conform to the passed Categorical
        new_target = np.asarray(new_target)
        if is_categorical_dtype(target):
            new_target = target._shallow_copy(new_target, name=self.name)
        else:
            new_target = Index(new_target, name=self.name)

        return new_target, indexer
Ejemplo n.º 3
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    def wrapper(self, other, axis=None):
        # Validate the axis parameter
        if axis is not None:
            self._get_axis_number(axis)

        if isinstance(other, ABCSeries):
            name = _maybe_match_name(self, other)
            if len(self) != len(other):
                raise ValueError('Series lengths must match to compare')
            return self._constructor(na_op(self.values, other.values),
                                     index=self.index, name=name)
        elif isinstance(other, pd.DataFrame):  # pragma: no cover
            return NotImplemented
        elif isinstance(other, (np.ndarray, pd.Index)):
            # do not check length of zerodim array
            # as it will broadcast
            if (not lib.isscalar(lib.item_from_zerodim(other)) and
                    len(self) != len(other)):
                raise ValueError('Lengths must match to compare')

            if isinstance(other, ABCPeriodIndex):
                # temp workaround until fixing GH 13637
                # tested in test_nat_comparisons
                # (pandas.tests.series.test_operators.TestSeriesOperators)
                return self._constructor(na_op(self.values,
                                               other.asobject.values),
                                         index=self.index)

            return self._constructor(na_op(self.values, np.asarray(other)),
                                     index=self.index).__finalize__(self)
        elif isinstance(other, pd.Categorical):
            if not is_categorical_dtype(self):
                msg = ("Cannot compare a Categorical for op {op} with Series "
                       "of dtype {typ}.\nIf you want to compare values, use "
                       "'series <op> np.asarray(other)'.")
                raise TypeError(msg.format(op=op, typ=self.dtype))

        if is_categorical_dtype(self):
            # cats are a special case as get_values() would return an ndarray,
            # which would then not take categories ordering into account
            # we can go directly to op, as the na_op would just test again and
            # dispatch to it.
            res = op(self.values, other)
        else:
            values = self.get_values()
            if isinstance(other, (list, np.ndarray)):
                other = np.asarray(other)

            res = na_op(values, other)
            if isscalar(res):
                raise TypeError('Could not compare %s type with Series' %
                                type(other))

            # always return a full value series here
            res = _values_from_object(res)

        res = pd.Series(res, index=self.index, name=self.name, dtype='bool')
        return res
Ejemplo n.º 4
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    def na_op(x, y):

        # dispatch to the categorical if we have a categorical
        # in either operand
        if is_categorical_dtype(x):
            return op(x, y)
        elif is_categorical_dtype(y) and not isscalar(y):
            return op(y, x)

        if is_object_dtype(x.dtype):
            result = _comp_method_OBJECT_ARRAY(op, x, y)
        else:

            # we want to compare like types
            # we only want to convert to integer like if
            # we are not NotImplemented, otherwise
            # we would allow datetime64 (but viewed as i8) against
            # integer comparisons
            if is_datetimelike_v_numeric(x, y):
                raise TypeError("invalid type comparison")

            # numpy does not like comparisons vs None
            if isscalar(y) and isnull(y):
                if name == '__ne__':
                    return np.ones(len(x), dtype=bool)
                else:
                    return np.zeros(len(x), dtype=bool)

            # we have a datetime/timedelta and may need to convert
            mask = None
            if (needs_i8_conversion(x) or
                    (not isscalar(y) and needs_i8_conversion(y))):

                if isscalar(y):
                    mask = isnull(x)
                    y = _index.convert_scalar(x, _values_from_object(y))
                else:
                    mask = isnull(x) | isnull(y)
                    y = y.view('i8')
                x = x.view('i8')

            try:
                result = getattr(x, name)(y)
                if result is NotImplemented:
                    raise TypeError("invalid type comparison")
            except AttributeError:
                result = op(x, y)

            if mask is not None and mask.any():
                result[mask] = masker

        return result
Ejemplo n.º 5
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def mode(values):
    """Returns the mode or mode(s) of the passed Series or ndarray (sorted)"""
    # must sort because hash order isn't necessarily defined.
    from pandas.core.series import Series

    if isinstance(values, Series):
        constructor = values._constructor
        values = values.values
    else:
        values = np.asanyarray(values)
        constructor = Series

    dtype = values.dtype
    if is_integer_dtype(values):
        values = _ensure_int64(values)
        result = constructor(sorted(htable.mode_int64(values)), dtype=dtype)

    elif issubclass(values.dtype.type, (np.datetime64, np.timedelta64)):
        dtype = values.dtype
        values = values.view(np.int64)
        result = constructor(sorted(htable.mode_int64(values)), dtype=dtype)

    elif is_categorical_dtype(values):
        result = constructor(values.mode())
    else:
        mask = isnull(values)
        values = _ensure_object(values)
        res = htable.mode_object(values, mask)
        try:
            res = sorted(res)
        except TypeError as e:
            warn("Unable to sort modes: %s" % e)
        result = constructor(res, dtype=dtype)

    return result
Ejemplo n.º 6
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    def _is_dtype_compat(self, other):
        """
        *this is an internal non-public method*

        provide a comparison between the dtype of self and other (coercing if
        needed)

        Raises
        ------
        TypeError if the dtypes are not compatible
        """
        if is_categorical_dtype(other):
            if isinstance(other, CategoricalIndex):
                other = other._values
            if not other.is_dtype_equal(self):
                raise TypeError("categories must match existing categories "
                                "when appending")
        else:
            values = other
            if not is_list_like(values):
                values = [values]
            other = CategoricalIndex(
                self._create_categorical(self,
                                         other,
                                         categories=self.categories,
                                         ordered=self.ordered))
            if not other.isin(values).all():
                raise TypeError("cannot append a non-category item to a "
                                "CategoricalIndex")

        return other
Ejemplo n.º 7
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    def test_constructor_categorical(self):
        cat = pd.Categorical([0, 1, 2, 0, 1, 2], ['a', 'b', 'c'],
                             fastpath=True)
        res = Series(cat)
        tm.assert_categorical_equal(res.values, cat)

        # GH12574
        self.assertRaises(
            ValueError, lambda: Series(pd.Categorical([1, 2, 3]),
                                       dtype='int64'))
        cat = Series(pd.Categorical([1, 2, 3]), dtype='category')
        self.assertTrue(is_categorical_dtype(cat))
        self.assertTrue(is_categorical_dtype(cat.dtype))
        s = Series([1, 2, 3], dtype='category')
        self.assertTrue(is_categorical_dtype(s))
        self.assertTrue(is_categorical_dtype(s.dtype))
Ejemplo n.º 8
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def mode(values):
    """Returns the mode or mode(s) of the passed Series or ndarray (sorted)"""
    # must sort because hash order isn't necessarily defined.
    from pandas.core.series import Series

    if isinstance(values, Series):
        constructor = values._constructor
        values = values.values
    else:
        values = np.asanyarray(values)
        constructor = Series

    dtype = values.dtype
    if is_integer_dtype(values):
        values = _ensure_int64(values)
        result = constructor(sorted(htable.mode_int64(values)), dtype=dtype)

    elif issubclass(values.dtype.type, (np.datetime64, np.timedelta64)):
        dtype = values.dtype
        values = values.view(np.int64)
        result = constructor(sorted(htable.mode_int64(values)), dtype=dtype)

    elif is_categorical_dtype(values):
        result = constructor(values.mode())
    else:
        mask = isnull(values)
        values = _ensure_object(values)
        res = htable.mode_object(values, mask)
        try:
            res = sorted(res)
        except TypeError as e:
            warn("Unable to sort modes: %s" % e)
        result = constructor(res, dtype=dtype)

    return result
Ejemplo n.º 9
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def nargsort(items, kind='quicksort', ascending=True, na_position='last'):
    """
    This is intended to be a drop-in replacement for np.argsort which
    handles NaNs. It adds ascending and na_position parameters.
    GH #6399, #5231
    """

    # specially handle Categorical
    if is_categorical_dtype(items):
        return items.argsort(ascending=ascending)

    items = np.asanyarray(items)
    idx = np.arange(len(items))
    mask = isnull(items)
    non_nans = items[~mask]
    non_nan_idx = idx[~mask]
    nan_idx = np.nonzero(mask)[0]
    if not ascending:
        non_nans = non_nans[::-1]
        non_nan_idx = non_nan_idx[::-1]
    indexer = non_nan_idx[non_nans.argsort(kind=kind)]
    if not ascending:
        indexer = indexer[::-1]
    # Finally, place the NaNs at the end or the beginning according to
    # na_position
    if na_position == 'last':
        indexer = np.concatenate([indexer, nan_idx])
    elif na_position == 'first':
        indexer = np.concatenate([nan_idx, indexer])
    else:
        raise ValueError('invalid na_position: {!r}'.format(na_position))
    return indexer
Ejemplo n.º 10
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    def test_constructor_categorical(self):
        cat = pd.Categorical([0, 1, 2, 0, 1, 2], ['a', 'b', 'c'],
                             fastpath=True)
        res = Series(cat)
        tm.assert_categorical_equal(res.values, cat)

        # GH12574
        self.assertRaises(
            ValueError,
            lambda: Series(pd.Categorical([1, 2, 3]), dtype='int64'))
        cat = Series(pd.Categorical([1, 2, 3]), dtype='category')
        self.assertTrue(is_categorical_dtype(cat))
        self.assertTrue(is_categorical_dtype(cat.dtype))
        s = Series([1, 2, 3], dtype='category')
        self.assertTrue(is_categorical_dtype(s))
        self.assertTrue(is_categorical_dtype(s.dtype))
Ejemplo n.º 11
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def nargsort(items, kind='quicksort', ascending=True, na_position='last'):
    """
    This is intended to be a drop-in replacement for np.argsort which
    handles NaNs. It adds ascending and na_position parameters.
    GH #6399, #5231
    """

    # specially handle Categorical
    if is_categorical_dtype(items):
        return items.argsort(ascending=ascending)

    items = np.asanyarray(items)
    idx = np.arange(len(items))
    mask = isnull(items)
    non_nans = items[~mask]
    non_nan_idx = idx[~mask]
    nan_idx = np.nonzero(mask)[0]
    if not ascending:
        non_nans = non_nans[::-1]
        non_nan_idx = non_nan_idx[::-1]
    indexer = non_nan_idx[non_nans.argsort(kind=kind)]
    if not ascending:
        indexer = indexer[::-1]
    # Finally, place the NaNs at the end or the beginning according to
    # na_position
    if na_position == 'last':
        indexer = np.concatenate([indexer, nan_idx])
    elif na_position == 'first':
        indexer = np.concatenate([nan_idx, indexer])
    else:
        raise ValueError('invalid na_position: {!r}'.format(na_position))
    return indexer
Ejemplo n.º 12
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    def _is_dtype_compat(self, other):
        """
        *this is an internal non-public method*

        provide a comparison between the dtype of self and other (coercing if
        needed)

        Raises
        ------
        TypeError if the dtypes are not compatible
        """
        if is_categorical_dtype(other):
            if isinstance(other, CategoricalIndex):
                other = other._values
            if not other.is_dtype_equal(self):
                raise TypeError("categories must match existing categories "
                                "when appending")
        else:
            values = other
            if not is_list_like(values):
                values = [values]
            other = CategoricalIndex(self._create_categorical(
                self, other, categories=self.categories, ordered=self.ordered))
            if not other.isin(values).all():
                raise TypeError("cannot append a non-category item to a "
                                "CategoricalIndex")

        return other
Ejemplo n.º 13
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    def test_basic(self):

        self.assertTrue(is_categorical_dtype(self.dtype))

        factor = Categorical(['a', 'b', 'b', 'a', 'a', 'c', 'c', 'c'])

        s = Series(factor, name='A')

        # dtypes
        self.assertTrue(is_categorical_dtype(s.dtype))
        self.assertTrue(is_categorical_dtype(s))
        self.assertFalse(is_categorical_dtype(np.dtype('float64')))

        self.assertTrue(is_categorical(s.dtype))
        self.assertTrue(is_categorical(s))
        self.assertFalse(is_categorical(np.dtype('float64')))
        self.assertFalse(is_categorical(1.0))
Ejemplo n.º 14
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    def test_basic(self):

        self.assertTrue(is_categorical_dtype(self.dtype))

        factor = Categorical(['a', 'b', 'b', 'a', 'a', 'c', 'c', 'c'])

        s = Series(factor, name='A')

        # dtypes
        self.assertTrue(is_categorical_dtype(s.dtype))
        self.assertTrue(is_categorical_dtype(s))
        self.assertFalse(is_categorical_dtype(np.dtype('float64')))

        self.assertTrue(is_categorical(s.dtype))
        self.assertTrue(is_categorical(s))
        self.assertFalse(is_categorical(np.dtype('float64')))
        self.assertFalse(is_categorical(1.0))
Ejemplo n.º 15
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 def astype(self, dtype, copy=True):
     if is_interval_dtype(dtype):
         if copy:
             self = self.copy()
         return self
     elif is_object_dtype(dtype):
         return Index(self.values, dtype=object)
     elif is_categorical_dtype(dtype):
         from pandas import Categorical
         return Categorical(self, ordered=True)
     raise ValueError('Cannot cast IntervalIndex to dtype %s' % dtype)
Ejemplo n.º 16
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def unconvert(values, dtype, compress=None):

    as_is_ext = isinstance(values, ExtType) and values.code == 0

    if as_is_ext:
        values = values.data

    if is_categorical_dtype(dtype):
        return values

    elif is_object_dtype(dtype):
        return np.array(values, dtype=object)

    dtype = pandas_dtype(dtype).base

    if not as_is_ext:
        values = values.encode('latin1')

    if compress:
        if compress == u'zlib':
            _check_zlib()
            decompress = zlib.decompress
        elif compress == u'blosc':
            _check_blosc()
            decompress = blosc.decompress
        else:
            raise ValueError("compress must be one of 'zlib' or 'blosc'")

        try:
            return np.frombuffer(
                _move_into_mutable_buffer(decompress(values)),
                dtype=dtype,
            )
        except _BadMove as e:
            # Pull the decompressed data off of the `_BadMove` exception.
            # We don't just store this in the locals because we want to
            # minimize the risk of giving users access to a `bytes` object
            # whose data is also given to a mutable buffer.
            values = e.args[0]
            if len(values) > 1:
                # The empty string and single characters are memoized in many
                # string creating functions in the capi. This case should not
                # warn even though we need to make a copy because we are only
                # copying at most 1 byte.
                warnings.warn(
                    'copying data after decompressing; this may mean that'
                    ' decompress is caching its result',
                    PerformanceWarning,
                )
                # fall through to copying `np.fromstring`

    # Copy the string into a numpy array.
    return np.fromstring(values, dtype=dtype)
Ejemplo n.º 17
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def unconvert(values, dtype, compress=None):

    as_is_ext = isinstance(values, ExtType) and values.code == 0

    if as_is_ext:
        values = values.data

    if is_categorical_dtype(dtype):
        return values

    elif is_object_dtype(dtype):
        return np.array(values, dtype=object)

    dtype = pandas_dtype(dtype).base

    if not as_is_ext:
        values = values.encode('latin1')

    if compress:
        if compress == u'zlib':
            _check_zlib()
            decompress = zlib.decompress
        elif compress == u'blosc':
            _check_blosc()
            decompress = blosc.decompress
        else:
            raise ValueError("compress must be one of 'zlib' or 'blosc'")

        try:
            return np.frombuffer(
                _move_into_mutable_buffer(decompress(values)),
                dtype=dtype,
            )
        except _BadMove as e:
            # Pull the decompressed data off of the `_BadMove` exception.
            # We don't just store this in the locals because we want to
            # minimize the risk of giving users access to a `bytes` object
            # whose data is also given to a mutable buffer.
            values = e.args[0]
            if len(values) > 1:
                # The empty string and single characters are memoized in many
                # string creating functions in the capi. This case should not
                # warn even though we need to make a copy because we are only
                # copying at most 1 byte.
                warnings.warn(
                    'copying data after decompressing; this may mean that'
                    ' decompress is caching its result',
                    PerformanceWarning,
                )
                # fall through to copying `np.fromstring`

    # Copy the string into a numpy array.
    return np.fromstring(values, dtype=dtype)
Ejemplo n.º 18
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def maybe_to_datetimelike(data, copy=False):
    """
    return a DelegatedClass of a Series that is datetimelike
      (e.g. datetime64[ns],timedelta64[ns] dtype or a Series of Periods)
    raise TypeError if this is not possible.

    Parameters
    ----------
    data : Series
    copy : boolean, default False
           copy the input data

    Returns
    -------
    DelegatedClass

    """
    from pandas import Series

    if not isinstance(data, Series):
        raise TypeError("cannot convert an object of type {0} to a "
                        "datetimelike index".format(type(data)))

    index = data.index
    name = data.name
    orig = data if is_categorical_dtype(data) else None
    if orig is not None:
        data = orig.values.categories

    if is_datetime64_dtype(data.dtype):
        return DatetimeProperties(DatetimeIndex(data, copy=copy, freq='infer'),
                                  index, name=name, orig=orig)
    elif is_datetime64tz_dtype(data.dtype):
        return DatetimeProperties(DatetimeIndex(data, copy=copy, freq='infer',
                                                ambiguous='infer'),
                                  index, data.name, orig=orig)
    elif is_timedelta64_dtype(data.dtype):
        return TimedeltaProperties(TimedeltaIndex(data, copy=copy,
                                                  freq='infer'), index,
                                   name=name, orig=orig)
    else:
        if is_period_arraylike(data):
            return PeriodProperties(PeriodIndex(data, copy=copy), index,
                                    name=name, orig=orig)
        if is_datetime_arraylike(data):
            return DatetimeProperties(DatetimeIndex(data, copy=copy,
                                                    freq='infer'), index,
                                      name=name, orig=orig)

    raise TypeError("cannot convert an object of type {0} to a "
                    "datetimelike index".format(type(data)))
Ejemplo n.º 19
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def maybe_to_datetimelike(data, copy=False):
    """
    return a DelegatedClass of a Series that is datetimelike
      (e.g. datetime64[ns],timedelta64[ns] dtype or a Series of Periods)
    raise TypeError if this is not possible.

    Parameters
    ----------
    data : Series
    copy : boolean, default False
           copy the input data

    Returns
    -------
    DelegatedClass

    """
    from pandas import Series

    if not isinstance(data, Series):
        raise TypeError("cannot convert an object of type {0} to a "
                        "datetimelike index".format(type(data)))

    index = data.index
    name = data.name
    orig = data if is_categorical_dtype(data) else None
    if orig is not None:
        data = orig.values.categories

    if is_datetime64_dtype(data.dtype):
        return DatetimeProperties(DatetimeIndex(data, copy=copy, freq='infer'),
                                  index, name=name, orig=orig)
    elif is_datetime64tz_dtype(data.dtype):
        return DatetimeProperties(DatetimeIndex(data, copy=copy, freq='infer',
                                                ambiguous='infer'),
                                  index, data.name, orig=orig)
    elif is_timedelta64_dtype(data.dtype):
        return TimedeltaProperties(TimedeltaIndex(data, copy=copy,
                                                  freq='infer'), index,
                                   name=name, orig=orig)
    else:
        if is_period_arraylike(data):
            return PeriodProperties(PeriodIndex(data, copy=copy), index,
                                    name=name, orig=orig)
        if is_datetime_arraylike(data):
            return DatetimeProperties(DatetimeIndex(data, copy=copy,
                                                    freq='infer'), index,
                                      name=name, orig=orig)

    raise TypeError("cannot convert an object of type {0} to a "
                    "datetimelike index".format(type(data)))
Ejemplo n.º 20
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    def test_setitem(self):

        df = DataFrame({'A': range(10)})
        s = pd.cut(df.A, 5)
        self.assertIsInstance(s.cat.categories, IntervalIndex)

        # B & D end up as Categoricals
        # the remainer are converted to in-line objects
        # contining an IntervalIndex.values
        df['B'] = s
        df['C'] = np.array(s)
        df['D'] = s.values
        df['E'] = np.array(s.values)

        assert is_categorical_dtype(df['B'])
        assert is_interval_dtype(df['B'].cat.categories)
        assert is_categorical_dtype(df['D'])
        assert is_interval_dtype(df['D'].cat.categories)

        assert is_object_dtype(df['C'])
        assert is_object_dtype(df['E'])

        # they compare equal as Index
        # when converted to numpy objects
        c = lambda x: Index(np.array(x))
        tm.assert_index_equal(c(df.B), c(df.B), check_names=False)
        tm.assert_index_equal(c(df.B), c(df.C), check_names=False)
        tm.assert_index_equal(c(df.B), c(df.D), check_names=False)
        tm.assert_index_equal(c(df.B), c(df.D), check_names=False)

        # B & D are the same Series
        tm.assert_series_equal(df['B'], df['B'], check_names=False)
        tm.assert_series_equal(df['B'], df['D'], check_names=False)

        # C & E are the same Series
        tm.assert_series_equal(df['C'], df['C'], check_names=False)
        tm.assert_series_equal(df['C'], df['E'], check_names=False)
Ejemplo n.º 21
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def duplicated(values, keep='first'):
    """
    Return boolean ndarray denoting duplicate values.

    .. versionadded:: 0.19.0

    Parameters
    ----------
    values : ndarray-like
        Array over which to check for duplicate values.
    keep : {'first', 'last', False}, default 'first'
        - ``first`` : Mark duplicates as ``True`` except for the first
          occurrence.
        - ``last`` : Mark duplicates as ``True`` except for the last
          occurrence.
        - False : Mark all duplicates as ``True``.

    Returns
    -------
    duplicated : ndarray
    """

    dtype = values.dtype

    # no need to revert to original type
    if needs_i8_conversion(dtype):
        values = values.view(np.int64)
    elif is_period_arraylike(values):
        from pandas.tseries.period import PeriodIndex
        values = PeriodIndex(values).asi8
    elif is_categorical_dtype(dtype):
        values = values.values.codes
    elif isinstance(values, (ABCSeries, ABCIndex)):
        values = values.values

    if is_signed_integer_dtype(dtype):
        values = _ensure_int64(values)
        duplicated = htable.duplicated_int64(values, keep=keep)
    elif is_unsigned_integer_dtype(dtype):
        values = _ensure_uint64(values)
        duplicated = htable.duplicated_uint64(values, keep=keep)
    elif is_float_dtype(dtype):
        values = _ensure_float64(values)
        duplicated = htable.duplicated_float64(values, keep=keep)
    else:
        values = _ensure_object(values)
        duplicated = htable.duplicated_object(values, keep=keep)

    return duplicated
Ejemplo n.º 22
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def duplicated(values, keep='first'):
    """
    Return boolean ndarray denoting duplicate values.

    .. versionadded:: 0.19.0

    Parameters
    ----------
    values : ndarray-like
        Array over which to check for duplicate values.
    keep : {'first', 'last', False}, default 'first'
        - ``first`` : Mark duplicates as ``True`` except for the first
          occurrence.
        - ``last`` : Mark duplicates as ``True`` except for the last
          occurrence.
        - False : Mark all duplicates as ``True``.

    Returns
    -------
    duplicated : ndarray
    """

    dtype = values.dtype

    # no need to revert to original type
    if needs_i8_conversion(dtype):
        values = values.view(np.int64)
    elif is_period_arraylike(values):
        from pandas.tseries.period import PeriodIndex
        values = PeriodIndex(values).asi8
    elif is_categorical_dtype(dtype):
        values = values.values.codes
    elif isinstance(values, (ABCSeries, ABCIndex)):
        values = values.values

    if is_signed_integer_dtype(dtype):
        values = _ensure_int64(values)
        duplicated = htable.duplicated_int64(values, keep=keep)
    elif is_unsigned_integer_dtype(dtype):
        values = _ensure_uint64(values)
        duplicated = htable.duplicated_uint64(values, keep=keep)
    elif is_float_dtype(dtype):
        values = _ensure_float64(values)
        duplicated = htable.duplicated_float64(values, keep=keep)
    else:
        values = _ensure_object(values)
        duplicated = htable.duplicated_object(values, keep=keep)

    return duplicated
Ejemplo n.º 23
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    def test_categorical_ordering(self):
        parsed_115 = read_stata(self.dta19_115)
        parsed_117 = read_stata(self.dta19_117)

        parsed_115_unordered = read_stata(self.dta19_115,
                                          order_categoricals=False)
        parsed_117_unordered = read_stata(self.dta19_117,
                                          order_categoricals=False)
        for col in parsed_115:
            if not is_categorical_dtype(parsed_115[col]):
                continue
            self.assertEqual(True, parsed_115[col].cat.ordered)
            self.assertEqual(True, parsed_117[col].cat.ordered)
            self.assertEqual(False, parsed_115_unordered[col].cat.ordered)
            self.assertEqual(False, parsed_117_unordered[col].cat.ordered)
Ejemplo n.º 24
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def as_json_table_type(x):
    """
    Convert a NumPy / pandas type to its corresponding json_table.

    Parameters
    ----------
    x : array or dtype

    Returns
    -------
    t : str
        the Table Schema data types

    Notes
    -----
    This table shows the relationship between NumPy / pandas dtypes,
    and Table Schema dtypes.

    ==============  =================
    Pandas type     Table Schema type
    ==============  =================
    int64           integer
    float64         number
    bool            boolean
    datetime64[ns]  datetime
    timedelta64[ns] duration
    object          str
    categorical     any
    =============== =================
    """
    if is_integer_dtype(x):
        return 'integer'
    elif is_bool_dtype(x):
        return 'boolean'
    elif is_numeric_dtype(x):
        return 'number'
    elif (is_datetime64_dtype(x) or is_datetime64tz_dtype(x) or
          is_period_dtype(x)):
        return 'datetime'
    elif is_timedelta64_dtype(x):
        return 'duration'
    elif is_categorical_dtype(x):
        return 'any'
    elif is_string_dtype(x):
        return 'string'
    else:
        return 'any'
Ejemplo n.º 25
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def mode(values):
    """
    Returns the mode(s) of an array.

    Parameters
    ----------
    values : array-like
        Array over which to check for duplicate values.

    Returns
    -------
    mode : Series
    """

    # must sort because hash order isn't necessarily defined.
    from pandas.core.series import Series

    if isinstance(values, Series):
        constructor = values._constructor
        values = values.values
    else:
        values = np.asanyarray(values)
        constructor = Series

    dtype = values.dtype
    if is_signed_integer_dtype(values):
        values = _ensure_int64(values)
        result = constructor(np.sort(htable.mode_int64(values)), dtype=dtype)
    elif is_unsigned_integer_dtype(values):
        values = _ensure_uint64(values)
        result = constructor(np.sort(htable.mode_uint64(values)), dtype=dtype)
    elif issubclass(values.dtype.type, (np.datetime64, np.timedelta64)):
        dtype = values.dtype
        values = values.view(np.int64)
        result = constructor(np.sort(htable.mode_int64(values)), dtype=dtype)
    elif is_categorical_dtype(values):
        result = constructor(values.mode())
    else:
        values = _ensure_object(values)
        res = htable.mode_object(values)
        try:
            res = np.sort(res)
        except TypeError as e:
            warn("Unable to sort modes: %s" % e)
        result = constructor(res, dtype=dtype)

    return result
Ejemplo n.º 26
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def as_json_table_type(x):
    """
    Convert a NumPy / pandas type to its corresponding json_table.

    Parameters
    ----------
    x : array or dtype

    Returns
    -------
    t : str
        the Table Schema data types

    Notes
    -----
    This table shows the relationship between NumPy / pandas dtypes,
    and Table Schema dtypes.

    ==============  =================
    Pandas type     Table Schema type
    ==============  =================
    int64           integer
    float64         number
    bool            boolean
    datetime64[ns]  datetime
    timedelta64[ns] duration
    object          str
    categorical     any
    =============== =================
    """
    if is_integer_dtype(x):
        return 'integer'
    elif is_bool_dtype(x):
        return 'boolean'
    elif is_numeric_dtype(x):
        return 'number'
    elif (is_datetime64_dtype(x) or is_datetime64tz_dtype(x)
          or is_period_dtype(x)):
        return 'datetime'
    elif is_timedelta64_dtype(x):
        return 'duration'
    elif is_categorical_dtype(x):
        return 'any'
    elif is_string_dtype(x):
        return 'string'
    else:
        return 'any'
Ejemplo n.º 27
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def mode(values):
    """
    Returns the mode(s) of an array.

    Parameters
    ----------
    values : array-like
        Array over which to check for duplicate values.

    Returns
    -------
    mode : Series
    """

    # must sort because hash order isn't necessarily defined.
    from pandas.core.series import Series

    if isinstance(values, Series):
        constructor = values._constructor
        values = values.values
    else:
        values = np.asanyarray(values)
        constructor = Series

    dtype = values.dtype
    if is_signed_integer_dtype(values):
        values = _ensure_int64(values)
        result = constructor(np.sort(htable.mode_int64(values)), dtype=dtype)
    elif is_unsigned_integer_dtype(values):
        values = _ensure_uint64(values)
        result = constructor(np.sort(htable.mode_uint64(values)), dtype=dtype)
    elif issubclass(values.dtype.type, (np.datetime64, np.timedelta64)):
        dtype = values.dtype
        values = values.view(np.int64)
        result = constructor(np.sort(htable.mode_int64(values)), dtype=dtype)
    elif is_categorical_dtype(values):
        result = constructor(values.mode())
    else:
        values = _ensure_object(values)
        res = htable.mode_object(values)
        try:
            res = np.sort(res)
        except TypeError as e:
            warn("Unable to sort modes: %s" % e)
        result = constructor(res, dtype=dtype)

    return result
Ejemplo n.º 28
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    def hash_array(vals, encoding='utf8', hash_key=None, categorize=True):
        if hash_key is None:
            hash_key = _default_hash_key

        # For categoricals, we hash the categories, then remap the codes to the
        # hash values. (This check is above the complex check so that we don't
        # ask numpy if categorical is a subdtype of complex, as it will choke.
        if is_categorical_dtype(vals.dtype):
            return _hash_categorical(vals, encoding, hash_key)

        # we'll be working with everything as 64-bit values, so handle this
        # 128-bit value early
        if np.issubdtype(vals.dtype, np.complex128):
            return hash_array(vals.real) + 23 * hash_array(vals.imag)

        # First, turn whatever array this is into unsigned 64-bit ints, if we
        # can manage it.
        if is_bool_array(vals):
            vals = vals.astype('u8')
        elif ((is_datetime64_dtype(vals) or is_timedelta64_dtype(vals)
               or is_numeric_dtype(vals)) and vals.dtype.itemsize <= 8):
            vals = vals.view('u{}'.format(vals.dtype.itemsize)).astype('u8')
        else:
            # With repeated values, its MUCH faster to categorize object
            # dtypes, then hash and rename categories. We allow skipping the
            # categorization when the values are known/likely to be unique.
            if categorize:
                codes, categories = pd.factorize(vals, sort=False)
                cat = pd.Categorical(codes,
                                     pd.Index(categories),
                                     ordered=False,
                                     fastpath=True)
                return _hash_categorical(cat, encoding, hash_key)

            vals = hash_object_array(vals, hash_key, encoding)

        # Then, redistribute these 64-bit ints within the space of 64-bit ints
        vals ^= vals >> 30
        vals *= np.uint64(0xbf58476d1ce4e5b9)
        vals ^= vals >> 27
        vals *= np.uint64(0x94d049bb133111eb)
        vals ^= vals >> 31
        return vals
Ejemplo n.º 29
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def lexsort_indexer(keys, orders=None, na_position='last'):
    labels = []
    shape = []
    if isinstance(orders, bool):
        orders = [orders] * len(keys)
    elif orders is None:
        orders = [True] * len(keys)

    for key, order in zip(keys, orders):

        # we are already a Categorical
        if is_categorical_dtype(key):
            c = key

        # create the Categorical
        else:
            c = Categorical(key, ordered=True)

        if na_position not in ['last', 'first']:
            raise ValueError('invalid na_position: {!r}'.format(na_position))

        n = len(c.categories)
        codes = c.codes.copy()

        mask = (c.codes == -1)
        if order:  # ascending
            if na_position == 'last':
                codes = np.where(mask, n, codes)
            elif na_position == 'first':
                codes += 1
        else:  # not order means descending
            if na_position == 'last':
                codes = np.where(mask, n, n - codes - 1)
            elif na_position == 'first':
                codes = np.where(mask, 0, n - codes)
        if mask.any():
            n += 1

        shape.append(n)
        labels.append(codes)

    return indexer_from_factorized(labels, shape)
Ejemplo n.º 30
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def lexsort_indexer(keys, orders=None, na_position='last'):
    labels = []
    shape = []
    if isinstance(orders, bool):
        orders = [orders] * len(keys)
    elif orders is None:
        orders = [True] * len(keys)

    for key, order in zip(keys, orders):

        # we are already a Categorical
        if is_categorical_dtype(key):
            c = key

        # create the Categorical
        else:
            c = Categorical(key, ordered=True)

        if na_position not in ['last', 'first']:
            raise ValueError('invalid na_position: {!r}'.format(na_position))

        n = len(c.categories)
        codes = c.codes.copy()

        mask = (c.codes == -1)
        if order:  # ascending
            if na_position == 'last':
                codes = np.where(mask, n, codes)
            elif na_position == 'first':
                codes += 1
        else:  # not order means descending
            if na_position == 'last':
                codes = np.where(mask, n, n - codes - 1)
            elif na_position == 'first':
                codes = np.where(mask, 0, n - codes)
        if mask.any():
            n += 1

        shape.append(n)
        labels.append(codes)

    return indexer_from_factorized(labels, shape)
Ejemplo n.º 31
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    def hash_array(vals, encoding='utf8', hash_key=None, categorize=True):
        if hash_key is None:
            hash_key = _default_hash_key

        # For categoricals, we hash the categories, then remap the codes to the
        # hash values. (This check is above the complex check so that we don't
        # ask numpy if categorical is a subdtype of complex, as it will choke.
        if is_categorical_dtype(vals.dtype):
            return _hash_categorical(vals, encoding, hash_key)

        # we'll be working with everything as 64-bit values, so handle this
        # 128-bit value early
        if np.issubdtype(vals.dtype, np.complex128):
            return hash_array(vals.real) + 23 * hash_array(vals.imag)

        # First, turn whatever array this is into unsigned 64-bit ints, if we
        # can manage it.
        if is_bool_array(vals):
            vals = vals.astype('u8')
        elif ((is_datetime64_dtype(vals) or
               is_timedelta64_dtype(vals) or
               is_numeric_dtype(vals)) and vals.dtype.itemsize <= 8):
            vals = vals.view('u{}'.format(vals.dtype.itemsize)).astype('u8')
        else:
            # With repeated values, its MUCH faster to categorize object
            # dtypes, then hash and rename categories. We allow skipping the
            # categorization when the values are known/likely to be unique.
            if categorize:
                codes, categories = pd.factorize(vals, sort=False)
                cat = pd.Categorical(codes, pd.Index(categories),
                                     ordered=False, fastpath=True)
                return _hash_categorical(cat, encoding, hash_key)

            vals = hash_object_array(vals, hash_key, encoding)

        # Then, redistribute these 64-bit ints within the space of 64-bit ints
        vals ^= vals >> 30
        vals *= np.uint64(0xbf58476d1ce4e5b9)
        vals ^= vals >> 27
        vals *= np.uint64(0x94d049bb133111eb)
        vals ^= vals >> 31
        return vals
Ejemplo n.º 32
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def make_field(arr, dtype=None):
    dtype = dtype or arr.dtype
    field = {'name': arr.name or 'values', 'type': as_json_table_type(dtype)}

    if is_categorical_dtype(arr):
        if hasattr(arr, 'categories'):
            cats = arr.categories
            ordered = arr.ordered
        else:
            cats = arr.cat.categories
            ordered = arr.cat.ordered
        field['constraints'] = {"enum": list(cats)}
        field['ordered'] = ordered
    elif is_period_dtype(arr):
        field['freq'] = arr.freqstr
    elif is_datetime64tz_dtype(arr):
        if hasattr(arr, 'dt'):
            field['tz'] = arr.dt.tz.zone
        else:
            field['tz'] = arr.tz.zone
    return field
Ejemplo n.º 33
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def make_field(arr, dtype=None):
    dtype = dtype or arr.dtype
    field = {'name': arr.name or 'values',
             'type': as_json_table_type(dtype)}

    if is_categorical_dtype(arr):
        if hasattr(arr, 'categories'):
            cats = arr.categories
            ordered = arr.ordered
        else:
            cats = arr.cat.categories
            ordered = arr.cat.ordered
        field['constraints'] = {"enum": list(cats)}
        field['ordered'] = ordered
    elif is_period_dtype(arr):
        field['freq'] = arr.freqstr
    elif is_datetime64tz_dtype(arr):
        if hasattr(arr, 'dt'):
            field['tz'] = arr.dt.tz.zone
        else:
            field['tz'] = arr.tz.zone
    return field
Ejemplo n.º 34
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def convert(values):
    """ convert the numpy values to a list """

    dtype = values.dtype

    if is_categorical_dtype(values):
        return values

    elif is_object_dtype(dtype):
        return values.ravel().tolist()

    if needs_i8_conversion(dtype):
        values = values.view('i8')
    v = values.ravel()

    if compressor == 'zlib':
        _check_zlib()

        # return string arrays like they are
        if dtype == np.object_:
            return v.tolist()

        # convert to a bytes array
        v = v.tostring()
        return ExtType(0, zlib.compress(v))

    elif compressor == 'blosc':
        _check_blosc()

        # return string arrays like they are
        if dtype == np.object_:
            return v.tolist()

        # convert to a bytes array
        v = v.tostring()
        return ExtType(0, blosc.compress(v, typesize=dtype.itemsize))

    # ndarray (on original dtype)
    return ExtType(0, v.tostring())
Ejemplo n.º 35
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def convert(values):
    """ convert the numpy values to a list """

    dtype = values.dtype

    if is_categorical_dtype(values):
        return values

    elif is_object_dtype(dtype):
        return values.ravel().tolist()

    if needs_i8_conversion(dtype):
        values = values.view('i8')
    v = values.ravel()

    if compressor == 'zlib':
        _check_zlib()

        # return string arrays like they are
        if dtype == np.object_:
            return v.tolist()

        # convert to a bytes array
        v = v.tostring()
        return ExtType(0, zlib.compress(v))

    elif compressor == 'blosc':
        _check_blosc()

        # return string arrays like they are
        if dtype == np.object_:
            return v.tolist()

        # convert to a bytes array
        v = v.tostring()
        return ExtType(0, blosc.compress(v, typesize=dtype.itemsize))

    # ndarray (on original dtype)
    return ExtType(0, v.tostring())
Ejemplo n.º 36
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def _get_data_algo(values, func_map):

    f = None

    if is_categorical_dtype(values):
        values = values._values_for_rank()

    if is_float_dtype(values):
        f = func_map['float64']
        values = _ensure_float64(values)

    elif needs_i8_conversion(values):
        f = func_map['int64']
        values = values.view('i8')

    elif is_signed_integer_dtype(values):
        f = func_map['int64']
        values = _ensure_int64(values)

    elif is_unsigned_integer_dtype(values):
        f = func_map['uint64']
        values = _ensure_uint64(values)

    else:
        values = _ensure_object(values)

        # its cheaper to use a String Hash Table than Object
        if lib.infer_dtype(values) in ['string']:
            try:
                f = func_map['string']
            except KeyError:
                pass

    if f is None:
        f = func_map['object']

    return f, values
Ejemplo n.º 37
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    def test_categorical_order(self):
        # Directly construct using expected codes
        # Format is is_cat, col_name, labels (in order), underlying data
        expected = [(True, 'ordered', ['a', 'b', 'c', 'd', 'e'], np.arange(5)),
                    (True, 'reverse', ['a', 'b', 'c',
                                       'd', 'e'], np.arange(5)[::-1]),
                    (True, 'noorder', ['a', 'b', 'c', 'd',
                                       'e'], np.array([2, 1, 4, 0, 3])),
                    (True, 'floating', [
                     'a', 'b', 'c', 'd', 'e'], np.arange(0, 5)),
                    (True, 'float_missing', [
                     'a', 'd', 'e'], np.array([0, 1, 2, -1, -1])),
                    (False, 'nolabel', [
                     1.0, 2.0, 3.0, 4.0, 5.0], np.arange(5)),
                    (True, 'int32_mixed', ['d', 2, 'e', 'b', 'a'],
                     np.arange(5))]
        cols = []
        for is_cat, col, labels, codes in expected:
            if is_cat:
                cols.append((col, pd.Categorical.from_codes(codes, labels)))
            else:
                cols.append((col, pd.Series(labels, dtype=np.float32)))
        expected = DataFrame.from_items(cols)

        # Read with and with out categoricals, ensure order is identical
        parsed_115 = read_stata(self.dta19_115)
        parsed_117 = read_stata(self.dta19_117)
        tm.assert_frame_equal(expected, parsed_115, check_categorical=False)
        tm.assert_frame_equal(expected, parsed_117, check_categorical=False)

        # Check identity of codes
        for col in expected:
            if is_categorical_dtype(expected[col]):
                tm.assert_series_equal(expected[col].cat.codes,
                                       parsed_115[col].cat.codes)
                tm.assert_index_equal(expected[col].cat.categories,
                                      parsed_115[col].cat.categories)
Ejemplo n.º 38
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def _bins_to_cuts(x,
                  bins,
                  right=True,
                  labels=None,
                  precision=3,
                  include_lowest=False,
                  dtype=None,
                  duplicates='raise'):

    if duplicates not in ['raise', 'drop']:
        raise ValueError("invalid value for 'duplicates' parameter, "
                         "valid options are: raise, drop")

    if isinstance(bins, IntervalIndex):
        # we have a fast-path here
        ids = bins.get_indexer(x)
        result = algos.take_nd(bins, ids)
        result = Categorical(result, categories=bins, ordered=True)
        return result, bins

    unique_bins = algos.unique(bins)
    if len(unique_bins) < len(bins) and len(bins) != 2:
        if duplicates == 'raise':
            raise ValueError("Bin edges must be unique: {}.\nYou "
                             "can drop duplicate edges by setting "
                             "the 'duplicates' kwarg".format(repr(bins)))
        else:
            bins = unique_bins

    side = 'left' if right else 'right'
    ids = _ensure_int64(bins.searchsorted(x, side=side))

    if include_lowest:
        ids[x == bins[0]] = 1

    na_mask = isnull(x) | (ids == len(bins)) | (ids == 0)
    has_nas = na_mask.any()

    if labels is not False:
        if labels is None:
            labels = _format_labels(bins,
                                    precision,
                                    right=right,
                                    include_lowest=include_lowest,
                                    dtype=dtype)
        else:
            if len(labels) != len(bins) - 1:
                raise ValueError('Bin labels must be one fewer than '
                                 'the number of bin edges')
        if not is_categorical_dtype(labels):
            labels = Categorical(labels, ordered=True)

        np.putmask(ids, na_mask, 0)
        result = algos.take_nd(labels, ids - 1)

    else:
        result = ids - 1
        if has_nas:
            result = result.astype(np.float64)
            np.putmask(result, na_mask, np.nan)

    return result, bins
Ejemplo n.º 39
0
def hash_array(vals, encoding='utf8', hash_key=None):
    """
    Given a 1d array, return an array of deterministic integers.

    .. versionadded:: 0.19.2

    Parameters
    ----------
    vals : ndarray
    encoding : string, default 'utf8'
        encoding for data & key when strings
    hash_key : string key to encode, default to _default_hash_key

    Returns
    -------
    1d uint64 numpy array of hash values, same length as the vals

    """

    # work with cagegoricals as ints. (This check is above the complex
    # check so that we don't ask numpy if categorical is a subdtype of
    # complex, as it will choke.
    if hash_key is None:
        hash_key = _default_hash_key

    if is_categorical_dtype(vals.dtype):
        vals = vals.codes

    # we'll be working with everything as 64-bit values, so handle this
    # 128-bit value early
    if np.issubdtype(vals.dtype, np.complex128):
        return hash_array(vals.real) + 23 * hash_array(vals.imag)

    # MAIN LOGIC:
    inferred = infer_dtype(vals)

    # First, turn whatever array this is into unsigned 64-bit ints, if we can
    # manage it.
    if inferred == 'boolean':
        vals = vals.astype('u8')

    if (np.issubdtype(vals.dtype, np.datetime64) or
       np.issubdtype(vals.dtype, np.timedelta64) or
       np.issubdtype(vals.dtype, np.number)) and vals.dtype.itemsize <= 8:

        vals = vals.view('u{}'.format(vals.dtype.itemsize)).astype('u8')
    else:

        # its MUCH faster to categorize object dtypes, then hash and rename
        codes, categories = factorize(vals, sort=False)
        categories = Index(categories)
        c = Series(Categorical(codes, categories,
                               ordered=False, fastpath=True))
        vals = _hash.hash_object_array(categories.values,
                                       hash_key,
                                       encoding)

        # rename & extract
        vals = c.cat.rename_categories(Index(vals)).astype(np.uint64).values

    # Then, redistribute these 64-bit ints within the space of 64-bit ints
    vals ^= vals >> 30
    vals *= np.uint64(0xbf58476d1ce4e5b9)
    vals ^= vals >> 27
    vals *= np.uint64(0x94d049bb133111eb)
    vals ^= vals >> 31
    return vals
Ejemplo n.º 40
0
def hash_array(vals, encoding='utf8', hash_key=None):
    """
    Given a 1d array, return an array of deterministic integers.

    .. versionadded:: 0.19.2

    Parameters
    ----------
    vals : ndarray
    encoding : string, default 'utf8'
        encoding for data & key when strings
    hash_key : string key to encode, default to _default_hash_key

    Returns
    -------
    1d uint64 numpy array of hash values, same length as the vals

    """

    # work with cagegoricals as ints. (This check is above the complex
    # check so that we don't ask numpy if categorical is a subdtype of
    # complex, as it will choke.
    if hash_key is None:
        hash_key = _default_hash_key

    if is_categorical_dtype(vals.dtype):
        vals = vals.codes

    # we'll be working with everything as 64-bit values, so handle this
    # 128-bit value early
    if np.issubdtype(vals.dtype, np.complex128):
        return hash_array(vals.real) + 23 * hash_array(vals.imag)

    # MAIN LOGIC:
    inferred = infer_dtype(vals)

    # First, turn whatever array this is into unsigned 64-bit ints, if we can
    # manage it.
    if inferred == 'boolean':
        vals = vals.astype('u8')

    if (np.issubdtype(vals.dtype, np.datetime64)
            or np.issubdtype(vals.dtype, np.timedelta64) or np.issubdtype(
                vals.dtype, np.number)) and vals.dtype.itemsize <= 8:

        vals = vals.view('u{}'.format(vals.dtype.itemsize)).astype('u8')
    else:

        # its MUCH faster to categorize object dtypes, then hash and rename
        codes, categories = factorize(vals, sort=False)
        categories = Index(categories)
        c = Series(Categorical(codes, categories, ordered=False,
                               fastpath=True))
        vals = _hash.hash_object_array(categories.values, hash_key, encoding)

        # rename & extract
        vals = c.cat.rename_categories(Index(vals)).astype(np.uint64).values

    # Then, redistribute these 64-bit ints within the space of 64-bit ints
    vals ^= vals >> 30
    vals *= np.uint64(0xbf58476d1ce4e5b9)
    vals ^= vals >> 27
    vals *= np.uint64(0x94d049bb133111eb)
    vals ^= vals >> 31
    return vals
Ejemplo n.º 41
0
def hash_array(vals, encoding='utf8', hash_key=None, categorize=True):
    """
    Given a 1d array, return an array of deterministic integers.

    .. versionadded:: 0.19.2

    Parameters
    ----------
    vals : ndarray
    encoding : string, default 'utf8'
        encoding for data & key when strings
    hash_key : string key to encode, default to _default_hash_key
    categorize : bool, default True
        Whether to first categorize object arrays before hashing. This is more
        efficient when the array contains duplicate values.

        .. versionadded:: 0.20.0

    Returns
    -------
    1d uint64 numpy array of hash values, same length as the vals

    """

    if hash_key is None:
        hash_key = _default_hash_key

    # For categoricals, we hash the categories, then remap the codes to the
    # hash values. (This check is above the complex check so that we don't ask
    # numpy if categorical is a subdtype of complex, as it will choke.
    if is_categorical_dtype(vals.dtype):
        return _hash_categorical(vals, encoding, hash_key)

    # we'll be working with everything as 64-bit values, so handle this
    # 128-bit value early
    if np.issubdtype(vals.dtype, np.complex128):
        return hash_array(vals.real) + 23 * hash_array(vals.imag)

    # First, turn whatever array this is into unsigned 64-bit ints, if we can
    # manage it.
    if is_bool_array(vals):
        vals = vals.astype('u8')
    elif ((is_datetime64_dtype(vals) or is_timedelta64_dtype(vals)
           or is_numeric_dtype(vals)) and vals.dtype.itemsize <= 8):
        vals = vals.view('u{}'.format(vals.dtype.itemsize)).astype('u8')
    else:
        # With repeated values, its MUCH faster to categorize object dtypes,
        # then hash and rename categories. We allow skipping the categorization
        # when the values are known/likely to be unique.
        if categorize:
            codes, categories = factorize(vals, sort=False)
            cat = Categorical(codes,
                              Index(categories),
                              ordered=False,
                              fastpath=True)
            return _hash_categorical(cat, encoding, hash_key)

        vals = _hash.hash_object_array(vals, hash_key, encoding)

    # Then, redistribute these 64-bit ints within the space of 64-bit ints
    vals ^= vals >> 30
    vals *= np.uint64(0xbf58476d1ce4e5b9)
    vals ^= vals >> 27
    vals *= np.uint64(0x94d049bb133111eb)
    vals ^= vals >> 31
    return vals
Ejemplo n.º 42
0
def hash_array(vals, encoding='utf8', hash_key=None, categorize=True):
    """
    Given a 1d array, return an array of deterministic integers.

    .. versionadded:: 0.19.2

    Parameters
    ----------
    vals : ndarray, Categorical
    encoding : string, default 'utf8'
        encoding for data & key when strings
    hash_key : string key to encode, default to _default_hash_key
    categorize : bool, default True
        Whether to first categorize object arrays before hashing. This is more
        efficient when the array contains duplicate values.

        .. versionadded:: 0.20.0

    Returns
    -------
    1d uint64 numpy array of hash values, same length as the vals

    """

    if not hasattr(vals, 'dtype'):
        raise TypeError("must pass a ndarray-like")

    if hash_key is None:
        hash_key = _default_hash_key

    # For categoricals, we hash the categories, then remap the codes to the
    # hash values. (This check is above the complex check so that we don't ask
    # numpy if categorical is a subdtype of complex, as it will choke.
    if is_categorical_dtype(vals.dtype):
        return _hash_categorical(vals, encoding, hash_key)

    # we'll be working with everything as 64-bit values, so handle this
    # 128-bit value early
    if np.issubdtype(vals.dtype, np.complex128):
        return hash_array(vals.real) + 23 * hash_array(vals.imag)

    # First, turn whatever array this is into unsigned 64-bit ints, if we can
    # manage it.
    if is_bool_array(vals):
        vals = vals.astype('u8')
    elif (is_datetime64_dtype(vals) or
          is_timedelta64_dtype(vals)):
        vals = vals.view('i8').astype('u8', copy=False)
    elif (is_numeric_dtype(vals) and vals.dtype.itemsize <= 8):
        vals = vals.view('u{}'.format(vals.dtype.itemsize)).astype('u8')
    else:
        # With repeated values, its MUCH faster to categorize object dtypes,
        # then hash and rename categories. We allow skipping the categorization
        # when the values are known/likely to be unique.
        if categorize:
            codes, categories = factorize(vals, sort=False)
            cat = Categorical(codes, Index(categories),
                              ordered=False, fastpath=True)
            return _hash_categorical(cat, encoding, hash_key)

        try:
            vals = _hash.hash_object_array(vals, hash_key, encoding)
        except TypeError:
            # we have mixed types
            vals = _hash.hash_object_array(vals.astype(str).astype(object),
                                           hash_key, encoding)

    # Then, redistribute these 64-bit ints within the space of 64-bit ints
    vals ^= vals >> 30
    vals *= np.uint64(0xbf58476d1ce4e5b9)
    vals ^= vals >> 27
    vals *= np.uint64(0x94d049bb133111eb)
    vals ^= vals >> 31
    return vals