Method update

qlib/data/cache.py:828–831

(self, data, sync=True)

                    self._data = pd.DataFrame()

        def update(self, data, sync=True):
            self._data = data.astype(np.int32).copy()
            if sync:
                self.sync_to_disk()

        def append_index(self, data, to_disk=True):
            data = data.astype(np.int32).copy()