def map(self, projection="nearest"):
        from .. import utils
        mapper = utils.get_mapper(self.subject, self.xfmname, projection)
        data = mapper(self)
        return data
Convert this VolumeData into a VertexData using the given sampler
dataset/ETHPy150Open gallantlab/pycortex/cortex/dataset/braindata.py/VolumeData.map