Python itertools.count方法代码示例

# 需要导入模块: import itertools [as 别名]
# 或者: from itertools import count [as 别名]
def format_mask(x):
    """
    Formats a mask into a readable string.
    Args:
        x (ndarray): an array with the mask;

    Returns:
        A readable string with the mask.
    """
    x = numpy.asanyarray(x)
    if len(x) == 0:
        return "(empty)"
    if x.dtype == bool:
        x = numpy.argwhere(x)[:, 0]
    grps = tuple(list(g) for _, g in groupby(x, lambda n, c=count(): n-next(c)))
    return ",".join("{:d}-{:d}".format(i[0], i[-1]) if len(i) > 1 else "{:d}".format(i[0]) for i in grps) 

# 需要导入模块: import itertools [as 别名]
# 或者: from itertools import count [as 别名]
def _jpeg_content_length(p):
    """
    Determines the length of the content of the JPEG file stored at `p` in bytes, i.e., size of the file without the
    header. Note: Note sure if this works for all JPEGs...
    :param p: path to a JPEG file
    :return: length of content
    """
    with open(p, 'rb') as f:
        last_byte = ''
        header_end_i = None
        for i in itertools.count():
            current_byte = f.read(1)
            if current_byte == b'':
                break
            # some files somehow contain multiple FF DA sequences, don't know what that means
            if header_end_i is None and last_byte == b'\xff' and current_byte == b'\xda':
                header_end_i = i
            last_byte = current_byte
        # at this point, i is equal to the size of the file
        return i - header_end_i - 2  # minus 2 because all JPEG files end in FF D0 

# 需要导入模块: import itertools [as 别名]
# 或者: from itertools import count [as 别名]
def __init__(self, pywren_config, storage_backend):
        self.pywren_config = pywren_config
        self.backend = storage_backend

        self._created_cobjects_n = itertools.count()

        try:
            module_location = 'pywren_ibm_cloud.storage.backends.{}'.format(self.backend)
            sb_module = importlib.import_module(module_location)
            storage_config = self.pywren_config[self.backend]
            storage_config['user_agent'] = 'pywren-ibm-cloud/{}'.format(__version__)
            StorageBackend = getattr(sb_module, 'StorageBackend')
            self.storage_handler = StorageBackend(storage_config)
        except Exception as e:
            raise NotImplementedError("An exception was produced trying to create the "
                                      "'{}' storage backend: {}".format(self.backend, e)) 

# 需要导入模块: import itertools [as 别名]
# 或者: from itertools import count [as 别名]
def __init__(*args, **kwds):
        '''Create a new, empty Counter object.  And if given, count elements
        from an input iterable.  Or, initialize the count from another mapping
        of elements to their counts.

        >>> c = Counter()                           # a new, empty counter
        >>> c = Counter('gallahad')                 # a new counter from an iterable
        >>> c = Counter({'a': 4, 'b': 2})           # a new counter from a mapping
        >>> c = Counter(a=4, b=2)                   # a new counter from keyword args

        '''
        if not args:
            raise TypeError("descriptor '__init__' of 'Counter' object "
                            "needs an argument")
        self = args[0]
        args = args[1:]
        if len(args) > 1:
            raise TypeError('expected at most 1 arguments, got %d' % len(args))
        super(Counter, self).__init__()
        self.update(*args, **kwds) 

# 需要导入模块: import itertools [as 别名]
# 或者: from itertools import count [as 别名]
def elements(self):
        '''Iterator over elements repeating each as many times as its count.

        >>> c = Counter('ABCABC')
        >>> sorted(c.elements())
        ['A', 'A', 'B', 'B', 'C', 'C']

        # Knuth's example for prime factors of 1836:  2**2 * 3**3 * 17**1
        >>> prime_factors = Counter({2: 2, 3: 3, 17: 1})
        >>> product = 1
        >>> for factor in prime_factors.elements():     # loop over factors
        ...     product *= factor                       # and multiply them
        >>> product
        1836

        Note, if an element's count has been set to zero or is a negative
        number, elements() will ignore it.

        '''
        # Emulate Bag.do from Smalltalk and Multiset.begin from C++.
        return _chain.from_iterable(_starmap(_repeat, self.items()))

    # Override dict methods where necessary 

# 需要导入模块: import itertools [as 别名]
# 或者: from itertools import count [as 别名]
def __add__(self, other):
        '''Add counts from two counters.

        >>> Counter('abbb') + Counter('bcc')
        Counter({'b': 4, 'c': 2, 'a': 1})

        '''
        if not isinstance(other, Counter):
            return NotImplemented
        result = Counter()
        for elem, count in self.items():
            newcount = count + other[elem]
            if newcount > 0:
                result[elem] = newcount
        for elem, count in other.items():
            if elem not in self and count > 0:
                result[elem] = count
        return result 

# 需要导入模块: import itertools [as 别名]
# 或者: from itertools import count [as 别名]
def __sub__(self, other):
        ''' Subtract count, but keep only results with positive counts.

        >>> Counter('abbbc') - Counter('bccd')
        Counter({'b': 2, 'a': 1})

        '''
        if not isinstance(other, Counter):
            return NotImplemented
        result = Counter()
        for elem, count in self.items():
            newcount = count - other[elem]
            if newcount > 0:
                result[elem] = newcount
        for elem, count in other.items():
            if elem not in self and count < 0:
                result[elem] = 0 - count
        return result 

# 需要导入模块: import itertools [as 别名]
# 或者: from itertools import count [as 别名]
def __or__(self, other):
        '''Union is the maximum of value in either of the input counters.

        >>> Counter('abbb') | Counter('bcc')
        Counter({'b': 3, 'c': 2, 'a': 1})

        '''
        if not isinstance(other, Counter):
            return NotImplemented
        result = Counter()
        for elem, count in self.items():
            other_count = other[elem]
            newcount = other_count if count < other_count else count
            if newcount > 0:
                result[elem] = newcount
        for elem, count in other.items():
            if elem not in self and count > 0:
                result[elem] = count
        return result 

# 需要导入模块: import itertools [as 别名]
# 或者: from itertools import count [as 别名]
def __and__(self, other):
        ''' Intersection is the minimum of corresponding counts.

        >>> Counter('abbb') & Counter('bcc')
        Counter({'b': 1})

        '''
        if not isinstance(other, Counter):
            return NotImplemented
        result = Counter()
        for elem, count in self.items():
            other_count = other[elem]
            newcount = count if count < other_count else other_count
            if newcount > 0:
                result[elem] = newcount
        return result 

# 需要导入模块: import itertools [as 别名]
# 或者: from itertools import count [as 别名]
def count(start=0, step=1):
    """
    ``itertools.count`` in Py 2.6 doesn't accept a step
    parameter. This is an enhanced version of ``itertools.count``
    for Py2.6 equivalent to ``itertools.count`` in Python 2.7+.
    """
    while True:
        yield start
        start += step


########################################################################
###  ChainMap (helper for configparser and string.Template)
###  From the Py3.4 source code. See also:
###    https://github.com/kkxue/Py2ChainMap/blob/master/py2chainmap.py
######################################################################## 

# 需要导入模块: import itertools [as 别名]
# 或者: from itertools import count [as 别名]
def parse_columns(text, base, count):
    # Parse the columns from the table definition. Columns start with
    # a short record length indicator, followed by type and sequence
    # information (each a short), and the name (prefixed by the length).
    columns = []
    for i in range(count):
        if len(text[base:]) < 8:
            break
        col_len, = struct.unpack_from('H', text, base)
        base = base + 2
        if len(text[base:]) < col_len:
            break
        col_data = text[base - 1:base - 1 + col_len]
        type_, col_id = struct.unpack_from('>HH', col_data, 0)
        text_len, = struct.unpack_from('>I', col_data, 4)
        col_name = decode_text(col_data[8:8 + text_len])
        if col_name is None:
            continue
        columns.append({
            'id': col_id,
            'name': col_name,
            'type': type_
        })
        base = base + col_len
    return columns 

# 需要导入模块: import itertools [as 别名]
# 或者: from itertools import count [as 别名]
def _flatten_index(data):
    """Flatten the index as a combination of the former index and the columns."""
    data = copy.deepcopy(data)
    data_flat = []
    counter = itertools.count()

    for series_or_df in data:
        series_or_df.index = series_or_df.index.map(str)
        # Unstack pandas.DataFrames and pandas.Series to add
        # columns/name to index.
        if isinstance(series_or_df, pd.DataFrame):
            df = series_or_df.rename(columns=str)
        # pandas.Series without a name are named using a counter to avoid duplicate
        # indexes.
        elif isinstance(series_or_df, pd.Series) and series_or_df.name is None:
            df = series_or_df.to_frame(name=str(next(counter)))
        else:
            df = series_or_df.to_frame(str(series_or_df.name))

        # Columns to the index.
        df = df.unstack()
        df.index = df.index.to_flat_index().str.join("_")
        data_flat.append(df)

    return pd.concat(data_flat) 

# 需要导入模块: import itertools [as 别名]
# 或者: from itertools import count [as 别名]
def read(self, count=None):
        if self.closed:
            raise ValueError('read of closed file.')

        if count is None or count < 0:
            count = max(self.size - self.tell(), 0)

        data = b''
        while count > 0:
            # Go to current offset, possibly opening new file.
            self.seek(0, 1)
            extra = self.fh.read(count)
            if not extra:
                break
            count -= len(extra)
            if not data:  # avoid copies for first read.
                data = extra
            else:
                data += extra

        return data 

# 需要导入模块: import itertools [as 别名]
# 或者: from itertools import count [as 别名]
def test_threadlocal_garbage(self):
        if platform.system() == 'Darwin':
            self.skip('queue issues; see #1474')
        success = itertools.count()

        def getpage():
            host = '%s:%s' % (self.interface(), self.PORT)
            if self.scheme == 'https':
                c = HTTPSConnection(host)
            else:
                c = HTTPConnection(host)
            try:
                c.putrequest('GET', '/')
                c.endheaders()
                response = c.getresponse()
                body = response.read()
                self.assertEqual(response.status, 200)
                self.assertEqual(body, b'Hello world!')
            finally:
                c.close()
            next(success)

        ITERATIONS = 25

        ts = [
            threading.Thread(target=getpage)
            for _ in range(ITERATIONS)
        ]

        for t in ts:
            t.start()

        for t in ts:
            t.join()

        self.assertEqual(next(success), ITERATIONS) 

# 需要导入模块: import itertools [as 别名]
# 或者: from itertools import count [as 别名]
def __init__(self, initial_content: BatchOfKwargs = None):
        self._register: t.Dict[int, Dto] = {}
        self._id_generator = count(1)
        if initial_content:
            self.batch_insert(initial_content)