def to_cpu(self):
        if self.use_gpu:
            self.threshold = cuda.to_cpu(self.threshold)
            self.values = cuda.to_cpu(self.values)
            self.use_gpu = False
Make a sampler CPU mode.
dataset/ETHPy150Open pfnet/chainer/chainer/utils/walker_alias.py/WalkerAlias.to_cpu