Source code for torch_geometric.transforms.fixed_points

import re
import math

import torch
import numpy as np

from torch_geometric.transforms import BaseTransform

[docs]class FixedPoints(BaseTransform): r"""Samples a fixed number of :obj:`num` points and features from a point cloud. Args: num (int): The number of points to sample. replace (bool, optional): If set to :obj:`False`, samples points without replacement. (default: :obj:`True`) allow_duplicates (bool, optional): In case :obj:`replace` is :obj`False` and :obj:`num` is greater than the number of points, this option determines whether to add duplicated nodes to the output points or not. In case :obj:`allow_duplicates` is :obj:`False`, the number of output points might be smaller than :obj:`num`. In case :obj:`allow_duplicates` is :obj:`True`, the number of duplicated points are kept to a minimum. (default: :obj:`False`) """ def __init__(self, num, replace=True, allow_duplicates=False): self.num = num self.replace = replace self.allow_duplicates = allow_duplicates def __call__(self, data): num_nodes = data.num_nodes if self.replace: choice = np.random.choice(num_nodes, self.num, replace=True) choice = torch.from_numpy(choice).to(torch.long) elif not self.allow_duplicates: choice = torch.randperm(num_nodes)[:self.num] else: choice =[ torch.randperm(num_nodes) for _ in range(math.ceil(self.num / num_nodes)) ], dim=0)[:self.num] for key, item in data: if bool('edge', key)): continue if (torch.is_tensor(item) and item.size(0) == num_nodes and item.size(0) != 1): data[key] = item[choice] return data def __repr__(self) -> str: return f'{self.__class__.__name__}({self.num}, replace={self.replace})'