def get_timestamp(self, x, z):
        return self.metadata[x,z].timestamp
Return the indices to access (n, n) arrays, given a masking function.
dataset/ETHPy150Open twoolie/NBT/nbt/region.py/RegionFile.get_timestamp--crossover with--dataset/ETHPy150Open nipy/nitime/nitime/index_utils.py/mask_indices