Class RepeatedData

tensorpack/dataflow/common.py:361–392

Take data points from another DataFlow and produce them until it's exhausted for certain amount of times. i.e.: dp1, dp2, .... dpn, dp1, dp2, ....dpn

class RepeatedData(ProxyDataFlow):
    """ Take data points from another DataFlow and produce them until
        it's exhausted for certain amount of times. i.e.:
        dp1, dp2, .... dpn, dp1, dp2, ....dpn
    """

    def __init__(self, ds, num):
        """
        Args:
            ds (DataFlow): input DataFlow
            num (int): number of times to repeat ds.
                Set to -1 to repeat ``ds`` infinite times.
        """
        self.num = num
        super(RepeatedData, self).__init__(ds)

    def __len__(self):
        """
        Raises:
            :class:`ValueError` when num == -1.
        """
        if self.num == -1:
            raise NotImplementedError("__len__() is unavailable for infinite dataflow")
        return len(self.ds) * self.num

    def __iter__(self):
        if self.num == -1:
            while True:
                yield from self.ds
        else:
            for _ in range(self.num):
                yield from self.ds


class RepeatedDataPoint(ProxyDataFlow):