예제 #1
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def sort(pda):
    """
    Return a sorted copy of the array.
    
    Parameters
    ----------
    pda : pdarray
        The array to sort (int64 or float64)

    Returns
    -------
    pdarray, int64 or float64
        The sorted copy of pda

    Notes
    -----
    Uses a least-significant-digit radix sort, which is stable and resilient
    to non-uniformity in data but communication intensive.

    Examples
    --------
    >>> a = ak.randint(0, 10, 10)
    >>> sorted = ak.sort(a)
    >>> a
    array([0, 1, 1, 3, 4, 5, 7, 8, 8, 9])
    """
    if isinstance(pda, pdarray):
        if pda.size == 0:
            return zeros(0, dtype=int64)
        repMsg = generic_msg("sort {}".format(pda.name))
        return create_pdarray(repMsg)
    else:
        raise TypeError("must be pdarray {}".format(pda))
예제 #2
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 def __init__(self, values, **kwargs):
     if 'codes' in kwargs and 'categories' in kwargs:
         # This initialization is called by Categorical.from_codes()
         # The values arg is ignored
         self.codes = kwargs['codes']
         self.categories = kwargs['categories']            
         if 'permutation' in kwargs:
             self.permutation = kwargs['permutation']
         if 'segments' in kwargs:
             self.segments = kwargs['segments']
     else:
         # Typical initialization, called with values
         if not isinstance(values, Strings):
             raise ValueError("Categorical: inputs other than Strings not yet supported")
         g = GroupBy(values)
         self.categories = g.unique_keys
         self.codes = zeros(values.size, dtype=int64)
         self.codes[g.permutation] = g.broadcast(arange(self.categories.size))
         self.permutation = g.permutation
         self.segments = g.segments
     # Always set these values
     self.size = self.codes.size
     self.nlevels = self.categories.size
     self.ndim = self.codes.ndim
     self.shape = self.codes.shape
예제 #3
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def concatenate(arrays):
    """
    Concatenate an iterable of ``pdarray`` objects into one ``pdarray``.

    Parameters
    ----------
    arrays : iterable of ``pdarray``
        The arrays to concatenate. Must all have same dtype.

    Returns
    -------
    pdarray
        Single array containing all values, in original order

    Examples
    --------
    >>> ak.concatenate([ak.array([1, 2, 3]), ak.array([4, 5, 6])])
    array([1, 2, 3, 4, 5, 6])
    """
    size = 0
    dtype = None
    for a in arrays:
        if not isinstance(a, pdarray):
            raise ValueError("Argument must be an iterable of pdarrays")
        if dtype == None:
            dtype = a.dtype
        elif dtype != a.dtype:
            raise ValueError("All pdarrays must have same dtype")
        size += a.size
    if size == 0:
        return zeros(0, dtype=int64)
    repMsg = generic_msg("concatenate {} {}".format(
        len(arrays), ' '.join([a.name for a in arrays])))
    return create_pdarray(repMsg)
예제 #4
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    def concatenate(self, others : List[Categorical], ordered : bool=True) -> Categorical:
        """
        Merge this Categorical with other Categorical objects in the array, 
        concatenating the arrays and synchronizing the categories.

        Parameters
        ----------
        others : List[Categorical]
            The Categorical arrays to concatenate and merge with this one
        ordered : bool
            If True (default), the arrays will be appended in the
            order given. If False, array data may be interleaved
            in blocks, which can greatly improve performance but
            results in non-deterministic ordering of elements.

        Returns
        -------
        Categorical 
            The merged Categorical object
            
        Raises
        ------
        TypeError
            Raised if any others array objects are not Categorical objects

        Notes
        -----
        This operation can be expensive -- slower than concatenating Strings.
        """
        if isinstance(others, Categorical):
            others = [others]
        elif len(others) < 1:
            return self
        samecategories = True
        for c in others:
            if not isinstance(c, Categorical):
                raise TypeError(("Categorical: can only merge/concatenate " +
                                "with other Categoricals"))
            if (self.categories.size != c.categories.size) or not \
                                    (self.categories == c.categories).all():
                samecategories = False
        if samecategories:
            newvals = cast(pdarray, concatenate([self.codes] + [o.codes for o in others], ordered=ordered))
            return Categorical.from_codes(newvals, self.categories)
        else:
            g = GroupBy(concatenate([self.categories] + \
                                       [o.categories for o in others],
                                       ordered=False))
            newidx = g.unique_keys
            wherediditgo = zeros(newidx.size, dtype=akint64)
            wherediditgo[g.permutation] = arange(newidx.size)
            idxsizes = np.array([self.categories.size] + \
                                [o.categories.size for o in others])
            idxoffsets = np.cumsum(idxsizes) - idxsizes
            oldvals = concatenate([c + off for c, off in \
                                   zip([self.codes] + [o.codes for o in others], idxoffsets)],
                                  ordered=ordered)
            newvals = wherediditgo[oldvals]
            return Categorical.from_codes(newvals, newidx)
예제 #5
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    def broadcast(self, values : pdarray) -> pdarray:
        """
        Fill each group's segment with a constant value.

        Parameters
        ----------
        values : pdarray
            The values to put in each group's segment

        Returns
        -------
        pdarray
            The broadcast values
            
        Raises
        ------
        TypeError
            Raised if value is not a pdarray object
        ValueError
            Raised if the values array does not have one 
            value per segment

        Notes
        -----
        This function is a sparse analog of ``np.broadcast``. If a
        GroupBy object represents a sparse matrix (tensor), then
        this function takes a (dense) column vector and replicates
        each value to the non-zero elements in the corresponding row.

        The returned array is in permuted (grouped) order. To get
        back to the order of the array on which GroupBy was called,
        the user must invert the permutation (see below).

        Examples
        --------
        >>> a = ak.array([0, 1, 0, 1, 0])
        >>> values = ak.array([3, 5])
        >>> g = ak.GroupBy(a)
        # Result is in grouped order
        >>> g.broadcast(values)
        array([3, 3, 3, 5, 5]

        >>> b = ak.zeros_like(a)
        # Result is in original order
        >>> b[g.permutation] = g.broadcast(values)
        >>> b
        array([3, 5, 3, 5, 3])
        """

        if not isinstance(values, pdarray):
            raise TypeError("Vals must be pdarray")
        if values.size != self.segments.size:
            raise ValueError("Must have one value per segment")
        temp = zeros(self.size, values.dtype)
        if values.size == 0:
            return temp
        diffs = concatenate((array([values[0]]), values[1:] - values[:-1]))
        temp[self.segments] = diffs
        return cumsum(temp)
예제 #6
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def local_argsort(pda):
    if isinstance(pda, pdarray):
        if pda.size == 0:
            return zeros(0, dtype=int64)
        repMsg = generic_msg("localArgsort {}".format(pda.name))
        return create_pdarray(repMsg)
    else:
        raise TypeError("must be pdarray {}".format(pda))
예제 #7
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def argsort(
    pda: Union[pdarray, Strings, 'Categorical'],
    algorithm: SortingAlgorithm = SortingAlgorithm.RadixSortLSD
) -> pdarray:  # type: ignore
    """
    Return the permutation that sorts the array.
    
    Parameters
    ----------
    pda : pdarray or Strings or Categorical
        The array to sort (int64 or float64)

    Returns
    -------
    pdarray, int64
        The indices such that ``pda[indices]`` is sorted
        
    Raises
    ------
    TypeError
        Raised if the parameter is other than a pdarray or Strings

    See Also
    --------
    coargsort

    Notes
    -----
    Uses a least-significant-digit radix sort, which is stable and
    resilient to non-uniformity in data but communication intensive.

    Examples
    --------
    >>> a = ak.randint(0, 10, 10)
    >>> perm = ak.argsort(a)
    >>> a[perm]
    array([0, 1, 1, 3, 4, 5, 7, 8, 8, 9])
    """
    from arkouda.categorical import Categorical
    check_type(argname='argsort',
               value=pda,
               expected_type=Union[pdarray, Strings, Categorical])
    if hasattr(pda, "argsort"):
        return cast(Categorical, pda).argsort()
    if pda.size == 0:
        return zeros(0, dtype=int64)
    if isinstance(pda, Strings):
        name = '{}+{}'.format(pda.entry.name, "legacy_placeholder")
    else:
        name = pda.name
    repMsg = generic_msg(cmd="argsort",
                         args="{} {} {}".format(algorithm.name, pda.objtype,
                                                name))
    return create_pdarray(cast(str, repMsg))
예제 #8
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 def reset_categories(self):
     """
     Recompute the category labels, discarding any unused labels. This method
     is often useful after slicing or indexing a Categorical array, when the
     resulting array only contains a subset of the original categories. In
     this case, eliminating unused categories can speed up other operations.
     """
     g = GroupBy(self.codes)
     idx = self.categories[g.unique_keys]
     newvals = zeros(self.codes.size, int64)
     newvals[g.permutation] = g.broadcast(arange(idx.size))
     return Categorical.from_codes(newvals, idx, permutation=g.permutation, segments=g.segments)
예제 #9
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    def merge(self, others : List[Categorical]) -> Categorical:
        """
        Merge this Categorical with other Categorical objects in the array, 
        concatenating the arrays and synchronizing the categories.

        Parameters
        ----------
        others : List[Categorical]
            The Categorical arrays to concatenate and merge with this one

        Returns
        -------
        Categorical 
            The merged Categorical object
            
        Raises
        ------
        TypeError
            Raised if any others array objects are not Categorical objects

        Notes
        -----
        This operation can be expensive -- slower than concatenating Strings.
        """
        if isinstance(others, Categorical):
            others = [others]
        elif len(others) < 1:
            return self
        samecategories = True
        for c in others:
            if not isinstance(c, Categorical):
                raise TypeError(("Categorical: can only merge/concatenate " +
                                "with other Categoricals"))
            if (self.categories.size != c.categories.size) or not \
                                    (self.categories == c.categories).all():
                samecategories = False
        if samecategories:
            newvals = cast(pdarray, concatenate([self.codes] + [o.codes for o in others]))
            return Categorical.from_codes(newvals, self.categories)
        else:
            g = GroupBy(concatenate([self.categories] + \
                                       [o.categories for o in others]))
            newidx = g.unique_keys
            wherediditgo = zeros(newidx.size, dtype=akint64)
            wherediditgo[g.permutation] = arange(newidx.size)
            idxsizes = np.array([self.categories.size] + \
                                [o.categories.size for o in others])
            idxoffsets = np.cumsum(idxsizes) - idxsizes
            oldvals = concatenate([c.codes + off for c, off in zip([self.codes] \
                                    + [o.codes for o in others], idxoffsets)])
            newvals = wherediditgo[oldvals]
            return Categorical.from_codes(newvals, newidx)
예제 #10
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def sort(
        pda: pdarray,
        algorithm: SortingAlgorithm = SortingAlgorithm.RadixSortLSD
) -> pdarray:
    """
    Return a sorted copy of the array. Only sorts numeric arrays; 
    for Strings, use argsort.
    
    Parameters
    ----------
    pda : pdarray or Categorical
        The array to sort (int64 or float64)

    Returns
    -------
    pdarray, int64 or float64
        The sorted copy of pda

    Raises
    ------
    TypeError
        Raised if the parameter is not a pdarray
    ValueError
        Raised if sort attempted on a pdarray with an unsupported dtype
        such as bool

    See Also
    --------
    argsort

    Notes
    -----
    Uses a least-significant-digit radix sort, which is stable and resilient
    to non-uniformity in data but communication intensive.

    Examples
    --------
    >>> a = ak.randint(0, 10, 10)
    >>> sorted = ak.sort(a)
    >>> a
    array([0, 1, 1, 3, 4, 5, 7, 8, 8, 9])
    """
    if pda.size == 0:
        return zeros(0, dtype=int64)
    if pda.dtype not in numeric_dtypes:
        raise ValueError("ak.sort supports float64 or int64, not {}".format(
            pda.dtype))
    repMsg = generic_msg(cmd="sort",
                         args="{} {}".format(algorithm.name, pda.name))
    return create_pdarray(cast(str, repMsg))
예제 #11
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def coargsort(arrays):
    """
    Return the permutation that sorts the rows (left-to-right), if the
    input arrays are treated as columns.
    
    Parameters
    ----------
    arrays : iterable of pdarray
        The columns (int64 or float64) to sort by row

    Returns
    -------
    pdarray, int64
        The indices that permute the rows to sorted order

    See Also
    --------
    argsort

    Notes
    -----
    Uses a least-significant-digit radix sort, which is stable and resilient
    to non-uniformity in data but communication intensive. Starts with the
    last array and moves forward.

    Examples
    --------
    >>> a = ak.array([0, 1, 0, 1])
    >>> b = ak.array([1, 1, 0, 0])
    >>> perm = ak.coargsort([a, b])
    >>> perm
    array([2, 0, 3, 1])
    >>> a[perm]
    array([0, 0, 1, 1])
    >>> b[perm]
    array([0, 1, 0, 1])
    """
    size = -1
    for a in arrays:
        if not isinstance(a, pdarray):
            raise ValueError("Argument must be an iterable of pdarrays")
        if size == -1:
            size = a.size
        elif size != a.size:
            raise ValueError("All pdarrays must have same size")
    if size == 0:
        return zeros(0, dtype=int64)
    repMsg = generic_msg("coargsort {} {}".format(
        len(arrays), ' '.join([a.name for a in arrays])))
    return create_pdarray(repMsg)
예제 #12
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파일: sorting.py 프로젝트: ssempax1/arkouda
def argsort(pda: Union[pdarray, Strings, 'Categorical']) -> pdarray:
    """
    Return the permutation that sorts the array.
    
    Parameters
    ----------
    pda : pdarray or Strings or Categorical
        The array to sort (int64 or float64)

    Returns
    -------
    pdarray, int64
        The indices such that ``pda[indices]`` is sorted
        
    Raises
    ------
    TypeError
        Raised if the parameter is other than a pdarray or Strings

    See Also
    --------
    coargsort

    Notes
    -----
    Uses a least-significant-digit radix sort, which is stable and
    resilinent to non-uniformity in data but communication intensive.

    Examples
    --------
    >>> a = ak.randint(0, 10, 10)
    >>> perm = ak.argsort(a)
    >>> a[perm]
    array([0, 1, 1, 3, 4, 5, 7, 8, 8, 9])
    """
    if hasattr(pda, "argsort"):
        return pda.argsort()
    if pda.size == 0:
        return zeros(0, dtype=int64)
    if isinstance(pda, Strings):
        name = '{}+{}'.format(pda.offsets.name, pda.bytes.name)
    else:
        name = pda.name
    repMsg = generic_msg("argsort {} {}".format(pda.objtype, name))
    return create_pdarray(repMsg)
예제 #13
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파일: sorting.py 프로젝트: ssempax1/arkouda
def sort(pda: pdarray) -> pdarray:
    """
    Return a sorted copy of the array. Only sorts numeric arrays; 
    for Strings, use argsort.
    
    Parameters
    ----------
    pda : pdarray or Categorical
        The array to sort (int64 or float64)

    Returns
    -------
    pdarray, int64 or float64
        The sorted copy of pda

    Raises
    ------
    TypeError
        Raised if the parameter is not a pdarray
    RuntimeError
        Raised if sort attempted on a pdarray with an unsupported dtype

    See Also
    --------
    argsort

    Notes
    -----
    Uses a least-significant-digit radix sort, which is stable and resilient
    to non-uniformity in data but communication intensive.

    Examples
    --------
    >>> a = ak.randint(0, 10, 10)
    >>> sorted = ak.sort(a)
    >>> a
    array([0, 1, 1, 3, 4, 5, 7, 8, 8, 9])
    """
    if pda.size == 0:
        return zeros(0, dtype=int64)
    repMsg = generic_msg("sort {}".format(pda.name))
    return create_pdarray(repMsg)
예제 #14
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def argsort(pda):
    """
    Return the permutation that sorts the array.
    
    Parameters
    ----------
    pda : pdarray
        The array to sort (int64 or float64)

    Returns
    -------
    pdarray, int64
        The indices such that ``pda[indices]`` is sorted

    See Also
    --------
    coargsort

    Notes
    -----
    Uses a least-significant-digit radix sort, which is stable and resilient
    to non-uniformity in data but communication intensive.

    Examples
    --------
    >>> a = ak.randint(0, 10, 10)
    >>> perm = ak.argsort(a)
    >>> a[perm]
    array([0, 1, 1, 3, 4, 5, 7, 8, 8, 9])
    """
    if isinstance(pda, pdarray):
        if pda.size == 0:
            return zeros(0, dtype=int64)
        repMsg = generic_msg("argsort {}".format(pda.name))
        return create_pdarray(repMsg)
    else:
        raise TypeError("must be pdarray {}".format(pda))
예제 #15
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def coargsort(arrays: Sequence[Union[Strings, pdarray, 'Categorical']]) -> pdarray:  # type: ignore
    """
    Return the permutation that groups the rows (left-to-right), if the
    input arrays are treated as columns. The permutation sorts numeric
    columns, but not strings/Categoricals -- strings/Categoricals are grouped, but not ordered.
    
    Parameters
    ----------
    arrays : Sequence[Union[Strings, pdarray, Categorical]]
        The columns (int64, float64, Strings, or Categorical) to sort by row

    Returns
    -------
    pdarray, int64
        The indices that permute the rows to grouped order
        
    Raises
    ------
    ValueError
        Raised if the pdarrays are not of the same size or if the parameter
        is not an Iterable containing pdarrays, Strings, or Categoricals

    See Also
    --------
    argsort

    Notes
    -----
    Uses a least-significant-digit radix sort, which is stable and resilient
    to non-uniformity in data but communication intensive. Starts with the
    last array and moves forward. This sort operates directly on numeric types,
    but for Strings, it operates on a hash. Thus, while grouping of equivalent
    strings is guaranteed, lexicographic ordering of the groups is not. For Categoricals,
    coargsort sorts based on Categorical.codes which guarantees grouping of equivalent categories
    but not lexicographic ordering of those groups.

    Examples
    --------
    >>> a = ak.array([0, 1, 0, 1])
    >>> b = ak.array([1, 1, 0, 0])
    >>> perm = ak.coargsort([a, b])
    >>> perm
    array([2, 0, 3, 1])
    >>> a[perm]
    array([0, 0, 1, 1])
    >>> b[perm]
    array([0, 1, 0, 1])
    """
    from arkouda.categorical import Categorical
    check_type(argname='coargsort', value=arrays, expected_type=Sequence[Union[pdarray, Strings, Categorical]])
    size = -1
    anames = []
    atypes = []
    for a in arrays:
        if isinstance(a, (pdarray, Strings)):
            anames.append('+'.join(a._list_component_names()))
            atypes.append(a.objtype)
        elif isinstance(a, Categorical):
            anames.append(a.codes.name)
            atypes.append(a.objtype)
        else:
            raise ValueError("Argument must be an iterable of pdarrays, Strings, or Categoricals")
        if size == -1:
            size = a.size
        elif size != a.size:
            raise ValueError("All pdarrays, Strings, or Categoricals must be of the same size")
    if size == 0:
        return zeros(0, dtype=int64)
    repMsg = generic_msg(cmd="coargsort", args="{:n} {} {}".format(len(arrays), 
                                                                   ' '.join(anames), ' '.join(atypes)))
    return create_pdarray(cast(str, repMsg))
예제 #16
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파일: sorting.py 프로젝트: ssempax1/arkouda
def coargsort(arrays: Iterable[Union[Strings, pdarray]]) -> pdarray:
    """
    Return the permutation that groups the rows (left-to-right), if the
    input arrays are treated as columns. The permutation sorts numeric
    columns, but not strings -- strings are grouped, but not ordered.
    
    Parameters
    ----------
    arrays : iterable of pdarray or Strings
        The columns (int64, float64, or Strings) to sort by row

    Returns
    -------
    pdarray, int64
        The indices that permute the rows to grouped order
        
    Raises
    ------
    ValueError
        Raised if the pdarrays are not of the same size or if the parameter
        is not an Iterable containing pdarrays or Strings

    See Also
    --------
    argsort

    Notes
    -----
    Uses a least-significant-digit radix sort, which is stable and resilient
    to non-uniformity in data but communication intensive. Starts with the
    last array and moves forward. This sort operates directly on numeric types,
    but for Strings, it operates on a hash. Thus, while grouping of equivalent
    strings is guaranteed, lexicographic ordering of the groups is not.

    Examples
    --------
    >>> a = ak.array([0, 1, 0, 1])
    >>> b = ak.array([1, 1, 0, 0])
    >>> perm = ak.coargsort([a, b])
    >>> perm
    array([2, 0, 3, 1])
    >>> a[perm]
    array([0, 0, 1, 1])
    >>> b[perm]
    array([0, 1, 0, 1])
    """
    size = -1
    anames = []
    atypes = []
    for a in arrays:
        if isinstance(a, Strings):
            anames.append('{}+{}'.format(a.offsets.name, a.bytes.name))
            atypes.append(a.objtype)
        elif isinstance(a, pdarray):
            anames.append(a.name)
            atypes.append('pdarray')
        else:
            raise ValueError(
                "Argument must be an iterable of pdarrays or Strings")
        if size == -1:
            size = a.size
        elif size != a.size:
            raise ValueError(
                "All pdarrays or Strings must be of the same size")
    if size == 0:
        return zeros(0, dtype=int64)
    cmd = "coargsort"
    reqMsg = "{} {:n} {} {}".format(cmd, len(arrays), ' '.join(anames),
                                    ' '.join(atypes))
    repMsg = generic_msg(reqMsg)
    return create_pdarray(repMsg)
예제 #17
0
def in1d(
        pda1: Union[pdarray, Strings, 'Categorical'],
        pda2: Union[pdarray, Strings, 'Categorical'],  #type: ignore
        invert: bool = False) -> pdarray:  #type: ignore
    """
    Test whether each element of a 1-D array is also present in a second array.

    Returns a boolean array the same length as `pda1` that is True
    where an element of `pda1` is in `pda2` and False otherwise.

    Parameters
    ----------
    pda1 : pdarray or Strings or Categorical
        Input array.
    pda2 : pdarray or Strings or Categorical
        The values against which to test each value of `pda1`. Must be the 
        same type as `pda1`.
    invert : bool, optional
        If True, the values in the returned array are inverted (that is,
        False where an element of `pda1` is in `pda2` and True otherwise).
        Default is False. ``ak.in1d(a, b, invert=True)`` is equivalent
        to (but is faster than) ``~ak.in1d(a, b)``.

    Returns
    -------
    pdarray, bool
        The values `pda1[in1d]` are in `pda2`.
        
    Raises
    ------
    TypeError
        Raised if either pda1 or pda2 is not a pdarray, Strings, or 
        Categorical object or if invert is not a bool
    RuntimeError
        Raised if the dtype of either array is not supported

    See Also
    --------
    unique, intersect1d, union1d

    Notes
    -----
    `in1d` can be considered as an element-wise function version of the
    python keyword `in`, for 1-D sequences. ``in1d(a, b)`` is logically
    equivalent to ``ak.array([item in b for item in a])``, but is much
    faster and scales to arbitrarily large ``a``.
    
    ak.in1d is not supported for bool or float64 pdarrays

    Examples
    --------
    >>> ak.in1d(ak.array([-1, 0, 1]), ak.array([-2, 0, 2]))
    array([False, True, False])    
    
    >>> ak.in1d(ak.array(['one','two']),ak.array(['two', 'three','four','five']))
    array([False, True])
    """
    from arkouda.categorical import Categorical as Categorical_
    if isinstance(pda1, pdarray) or isinstance(pda1, Strings) or isinstance(
            pda1, Categorical_):
        # While isinstance(thing, type) can be called on a tuple of types, this causes an issue with mypy for unknown reasons.
        if pda1.size == 0:
            return zeros(0, dtype=bool)
    if isinstance(pda2, pdarray) or isinstance(pda2, Strings) or isinstance(
            pda2, Categorical_):
        if pda2.size == 0:
            return zeros(pda1.size, dtype=bool)
    if hasattr(pda1, 'categories'):
        return cast(Categorical_, pda1).in1d(pda2)
    elif isinstance(pda1, pdarray) and isinstance(pda2, pdarray):
        repMsg = generic_msg(cmd="in1d", args="{} {} {}".\
                             format(pda1.name, pda2.name, invert))
        return create_pdarray(repMsg)
    elif isinstance(pda1, Strings) and isinstance(pda2, Strings):
        repMsg = generic_msg(cmd="segmentedIn1d", args="{} {} {} {} {} {} {}".\
                                    format(pda1.objtype,
                                    pda1.entry.name,
                                    "legacy_placeholder",
                                    pda2.objtype,
                                    pda2.entry.name,
                                    "legacy_placeholder",
                                    invert))
        return create_pdarray(cast(str, repMsg))
    else:
        raise TypeError(
            'Both pda1 and pda2 must be pdarray, Strings, or Categorical')
예제 #18
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    def broadcast(self, values : pdarray) -> pdarray:
        """
        Fill each group's segment with a constant value.

        Parameters
        ----------
        values : pdarray
            The values to put in each group's segment

        Returns
        -------
        pdarray
            The broadcast values
            
        Raises
        ------
        TypeError
            Raised if value is not a pdarray object
        ValueError
            Raised if the values array does not have one 
            value per segment

        Notes
        -----
        This function is a sparse analog of ``np.broadcast``. If a
        GroupBy object represents a sparse matrix (tensor), then
        this function takes a (dense) column vector and replicates
        each value to the non-zero elements in the corresponding row.

        The returned array is in permuted (grouped) order. To get
        back to the order of the array on which GroupBy was called,
        the user must invert the permutation (see below).

        Examples
        --------
        >>> a = ak.array([0, 1, 0, 1, 0])
        >>> values = ak.array([3, 5])
        >>> g = ak.GroupBy(a)
        # Result is in grouped order
        >>> g.broadcast(values)
        array([3, 3, 3, 5, 5]

        >>> b = ak.zeros_like(a)
        # Result is in original order
        >>> b[g.permutation] = g.broadcast(values)
        >>> b
        array([3, 5, 3, 5, 3])
        
        >>> a = ak.randint(1,5,10)
        >>> a
        array([3, 1, 4, 4, 4, 1, 3, 3, 2, 2])
        >>> g = ak.GroupBy(a)
        >>> keys,counts = g.count()
        >>> g.broadcast(counts > 2)
        array([0, 0, 0, 0, 1, 1, 1, 1, 1, 1])
        >>> g.broadcast(counts == 3)
        array([0, 0, 0, 0, 1, 1, 1, 1, 1, 1])
        >>> g.broadcast(counts < 4)
        array([1, 1, 1, 1, 1, 1, 1, 1, 1, 1])
        """
        '''if values a boolean array, convert to an int64 array, which
           is needed for now because Arkouda does not support broadcasting
           of boolean arrays'''
        if values.dtype == np.bool:
            values = 1*values
        if values.size != self.segments.size:
            raise ValueError("Must have one value per segment")
        temp = zeros(self.size, values.dtype)
        if values.size == 0:
            return temp
        diffs = concatenate((array([values[0]]), values[1:] - values[:-1]))
        temp[self.segments] = diffs
        return cumsum(temp)