示例#1
0
文件: array.py 项目: AkiraKane/pandas
    def __new__(cls, data, sparse_index=None, index=None, kind='integer',
                fill_value=None, dtype=np.float64, copy=False):

        if index is not None:
            if data is None:
                data = np.nan
            if not lib.isscalar(data):
                raise Exception("must only pass scalars with an index ")
            values = np.empty(len(index), dtype='float64')
            values.fill(data)
            data = values

        if dtype is not None:
            dtype = np.dtype(dtype)
        is_sparse_array = isinstance(data, SparseArray)
        if fill_value is None:
            if is_sparse_array:
                fill_value = data.fill_value
            else:
                fill_value = nan

        if is_sparse_array:
            sparse_index = data.sp_index
            values = np.asarray(data)
        else:
            # array-like
            if sparse_index is None:
                values, sparse_index = make_sparse(data, kind=kind,
                                                   fill_value=fill_value)
            else:
                values = _sanitize_values(data)
                if len(values) != sparse_index.npoints:
                    raise AssertionError("Non array-like type {0} must have"
                                         " the same length as the"
                                         " index".format(type(values)))

        # Create array, do *not* copy data by default
        if copy:
            try:
                # ToDo: Can remove this error handling when we actually
                # support other dtypes
                subarr = np.array(values, dtype=dtype, copy=True)
            except ValueError:
                subarr = np.array(values, copy=True)
        else:
            try:
                subarr = np.asarray(values, dtype=dtype)
            except ValueError:
                subarr = np.asarray(values)

        # if we have a bool type, make sure that we have a bool fill_value
        if ((dtype is not None and issubclass(dtype.type, np.bool_)) or
                (data is not None and lib.is_bool_array(subarr))):
            if np.isnan(fill_value) or not fill_value:
                fill_value = False
            else:
                fill_value = bool(fill_value)

        # Change the class of the array to be the subclass type.
        return cls._simple_new(subarr, sparse_index, fill_value)
示例#2
0
    def __new__(cls, data, sparse_index=None, index=None, kind='integer',
                fill_value=None, dtype=np.float64, copy=False):

        if index is not None:
            if data is None:
                data = np.nan
            if not is_scalar(data):
                raise Exception("must only pass scalars with an index ")
            values = np.empty(len(index), dtype='float64')
            values.fill(data)
            data = values

        if dtype is not None:
            dtype = np.dtype(dtype)
        is_sparse_array = isinstance(data, SparseArray)
        if fill_value is None:
            if is_sparse_array:
                fill_value = data.fill_value
            else:
                fill_value = nan

        if is_sparse_array:
            sparse_index = data.sp_index
            values = np.asarray(data)
        else:
            # array-like
            if sparse_index is None:
                values, sparse_index = make_sparse(data, kind=kind,
                                                   fill_value=fill_value)
            else:
                values = _sanitize_values(data)
                if len(values) != sparse_index.npoints:
                    raise AssertionError("Non array-like type {0} must have"
                                         " the same length as the"
                                         " index".format(type(values)))

        # Create array, do *not* copy data by default
        if copy:
            try:
                # ToDo: Can remove this error handling when we actually
                # support other dtypes
                subarr = np.array(values, dtype=dtype, copy=True)
            except ValueError:
                subarr = np.array(values, copy=True)
        else:
            try:
                subarr = np.asarray(values, dtype=dtype)
            except ValueError:
                subarr = np.asarray(values)

        # if we have a bool type, make sure that we have a bool fill_value
        if ((dtype is not None and issubclass(dtype.type, np.bool_)) or
                (data is not None and lib.is_bool_array(subarr))):
            if np.isnan(fill_value) or not fill_value:
                fill_value = False
            else:
                fill_value = bool(fill_value)

        # Change the class of the array to be the subclass type.
        return cls._simple_new(subarr, sparse_index, fill_value)
示例#3
0
文件: common.py 项目: zkluo1/pandas
def _is_bool_indexer(key):
    if isinstance(key, np.ndarray) and key.dtype == np.object_:
        if not lib.is_bool_array(key):
            if isnull(key).any():
                raise ValueError("cannot index with vector containing " "NA / NaN values")
            return False
        return True
    elif isinstance(key, np.ndarray) and key.dtype == np.bool_:
        return True
    elif isinstance(key, list):
        try:
            return np.asarray(key).dtype == np.bool_
        except TypeError:  # pragma: no cover
            return False

    return False
示例#4
0
文件: common.py 项目: zkluo1/pandas
def _is_bool_indexer(key):
    if isinstance(key, np.ndarray) and key.dtype == np.object_:
        if not lib.is_bool_array(key):
            if isnull(key).any():
                raise ValueError('cannot index with vector containing '
                                 'NA / NaN values')
            return False
        return True
    elif isinstance(key, np.ndarray) and key.dtype == np.bool_:
        return True
    elif isinstance(key, list):
        try:
            return np.asarray(key).dtype == np.bool_
        except TypeError:  # pragma: no cover
            return False

    return False
示例#5
0
文件: hashing.py 项目: json87/dask
    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
示例#6
0
    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
示例#7
0
def is_bool_indexer(key):
    if isinstance(key, (ABCSeries, np.ndarray)):
        if key.dtype == np.object_:
            key = np.asarray(_values_from_object(key))

            if not lib.is_bool_array(key):
                if isnull(key).any():
                    raise ValueError('cannot index with vector containing '
                                     'NA / NaN values')
                return False
            return True
        elif key.dtype == np.bool_:
            return True
    elif isinstance(key, list):
        try:
            arr = np.asarray(key)
            return arr.dtype == np.bool_ and len(arr) == len(key)
        except TypeError:  # pragma: no cover
            return False

    return False
示例#8
0
文件: common.py 项目: Alias4bb/pandas
def is_bool_indexer(key):
    if isinstance(key, (ABCSeries, np.ndarray)):
        if key.dtype == np.object_:
            key = np.asarray(_values_from_object(key))

            if not lib.is_bool_array(key):
                if isnull(key).any():
                    raise ValueError('cannot index with vector containing '
                                     'NA / NaN values')
                return False
            return True
        elif key.dtype == np.bool_:
            return True
    elif isinstance(key, list):
        try:
            arr = np.asarray(key)
            return arr.dtype == np.bool_ and len(arr) == len(key)
        except TypeError:  # pragma: no cover
            return False

    return False
示例#9
0
文件: hashing.py 项目: kordek/pandas
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
示例#10
0
文件: array.py 项目: tdhock/pandas
    def __new__(cls,
                data,
                sparse_index=None,
                index=None,
                kind='integer',
                fill_value=None,
                dtype=np.float64,
                copy=False):

        if index is not None:
            if data is None:
                data = np.nan
            if not np.isscalar(data):
                raise Exception("must only pass scalars with an index ")
            values = np.empty(len(index), dtype='float64')
            values.fill(data)
            data = values

        if dtype is not None:
            dtype = np.dtype(dtype)
        is_sparse_array = isinstance(data, SparseArray)
        if fill_value is None:
            if is_sparse_array:
                fill_value = data.fill_value
            else:
                fill_value = nan

        if is_sparse_array:
            sparse_index = data.sp_index
            values = np.asarray(data)
        else:
            # array-like
            if sparse_index is None:
                values, sparse_index = make_sparse(data,
                                                   kind=kind,
                                                   fill_value=fill_value)
            else:
                values = data
                if len(values) != sparse_index.npoints:
                    raise AssertionError("Non array-like type {0} must have"
                                         " the same length as the"
                                         " index".format(type(values)))

        # Create array, do *not* copy data by default
        if copy:
            subarr = np.array(values, dtype=dtype, copy=True)
        else:
            subarr = np.asarray(values, dtype=dtype)

        # if we have a bool type, make sure that we have a bool fill_value
        if (dtype is not None and issubclass(dtype.type, np.bool_)) or (
                data is not None and lib.is_bool_array(subarr)):
            if np.isnan(fill_value) or not fill_value:
                fill_value = False
            else:
                fill_value = bool(fill_value)

        # Change the class of the array to be the subclass type.
        output = subarr.view(cls)
        output.sp_index = sparse_index
        output.fill_value = fill_value
        return output
示例#11
0
    def __new__(
        cls, data, sparse_index=None, index=None, kind='integer', fill_value=None,
            dtype=np.float64, copy=False):

        if index is not None:
            if data is None:
                data = np.nan
            if not np.isscalar(data):
                raise Exception("must only pass scalars with an index ")
            values = np.empty(len(index), dtype='float64')
            values.fill(data)
            data = values

        if dtype is not None:
            dtype = np.dtype(dtype)
        is_sparse_array = isinstance(data, SparseArray)
        if fill_value is None:
            if is_sparse_array:
                fill_value = data.fill_value
            else:
                fill_value = nan

        if is_sparse_array:
            sparse_index = data.sp_index
            values = np.asarray(data)
        else:
            # array-like
            if sparse_index is None:
                values, sparse_index = make_sparse(data, kind=kind,
                                                   fill_value=fill_value)
            else:
                values = data
                if len(values) != sparse_index.npoints:
                    raise AssertionError("Non array-like type {0} must have"
                                         " the same length as the"
                                         " index".format(type(values)))

        # Create array, do *not* copy data by default
        if copy:
            subarr = np.array(values, dtype=dtype, copy=True)
        else:
            subarr = np.asarray(values, dtype=dtype)

        # if we have a bool type, make sure that we have a bool fill_value
        if (dtype is not None and issubclass(dtype.type, np.bool_)) or (data is not None and lib.is_bool_array(subarr)):
            if np.isnan(fill_value) or not fill_value:
                fill_value = False
            else:
                fill_value = bool(fill_value)

        # Change the class of the array to be the subclass type.
        output = subarr.view(cls)
        output.sp_index = sparse_index
        output.fill_value = fill_value
        return output
示例#12
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