

作者 | 王建民
DGL团队发布了以生命科学为重点的软件包DGL-LifeSci。
尝试使用新的DGL--LifeSci并建立Attentive FP模型并可视化其预测结果。
基于深度图学习框架DGL
环境准备
DGL安装
conda install -c dglteam dgl #DGLv0.4.3
pip install dgllife
导入库
import matplotlib.pyplot as plt
import os
from rdkit import Chem
from rdkit.Chem import rdmolops, rdmolfiles
from rdkit import RDPaths
import dgl
import numpy as np
import random
import torch
import torch.nn as nn
import torch.nn.functional as F
from torch.utils.data import DataLoader
from torch.utils.data import Dataset
from dgl import model_zoo
from dgllife.model import AttentiveFPPredictor
from dgllife.utils import mol_to_complete_graph, mol_to_bigraph
from dgllife.utils import atom_type_one_hot
from dgllife.utils import atom_degree_one_hot
from dgllife.utils import atom_formal_charge
from dgllife.utils import atom_num_radical_electrons
from dgllife.utils import atom_hybridization_one_hot
from dgllife.utils import atom_total_num_H_one_hot
from dgllife.utils import one_hot_encoding
from dgllife.utils import CanonicalAtomFeaturizer
from dgllife.utils import CanonicalBondFeaturizer
from dgllife.utils import ConcatFeaturizer
from dgllife.utils import BaseAtomFeaturizer
from dgllife.utils import BaseBondFeaturizer
from dgllife.utils import one_hot_encoding
from dgl.data.utils import split_dataset
from functools import partial
from sklearn.metrics import roc_auc_score定义辅助函数
代码来源于dgl/example。
def chirality(atom):
try:
return one_hot_encoding(atom.GetProp('_CIPCode'), ['R', 'S']) + \
[atom.HasProp('_ChiralityPossible')]
except:
return [False, False] + [atom.HasProp('_ChiralityPossible')]
def collate_molgraphs(data):
"""Batching a list of datapoints for dataloader.
Parameters
----------
data : list of 3-tuples or 4-tuples.
Each tuple is for a single datapoint, consisting of
a SMILES, a DGLGraph, all-task labels and optionally
a binary mask indicating the existence of labels.
Returns
-------
smiles : list
List of smiles
bg : BatchedDGLGraph
Batched DGLGraphs
labels : Tensor of dtype float32 and shape (B, T)
Batched datapoint labels. B is len(data) and
T is the number of total tasks.
masks : Tensor of dtype float32 and shape (B, T)
Batched datapoint binary mask, indicating the
existence of labels. If binary masks are not
provided, return a tensor with ones.
"""
assert len(data[0]) in [3, 4], \
'Expect the tuple to be of length 3 or 4, got {:d}'.format(len(data[0]))
if len(data[0]) == 3:
smiles, graphs, labels = map(list, zip(*data))
masks = None
else:
smiles, graphs, labels, masks = map(list, zip(*data))
bg = dgl.batch(graphs)
bg.set_n_initializer(dgl.init.zero_initializer)
bg.set_e_initializer(dgl.init.zero_initializer)
labels = torch.stack(labels, dim=0)
if masks is None:
masks = torch.ones(labels.shape)
else:
masks = torch.stack(masks, dim=0)
return smiles, bg, labels, masks原子和键特征化器
atom_featurizer = BaseAtomFeaturizer(
{'hv': ConcatFeaturizer([
partial(atom_type_one_hot, allowable_set=[
'B', 'C', 'N', 'O', 'F', 'Si', 'P', 'S', 'Cl', 'As', 'Se', 'Br', 'Te', 'I', 'At'],
encode_unknown=True),
partial(atom_degree_one_hot, allowable_set=list(range(6))),
atom_formal_charge, atom_num_radical_electrons,
partial(atom_hybridization_one_hot, encode_unknown=True),
lambda atom: [0], # A placeholder for aromatic information,
atom_total_num_H_one_hot, chirality
],
)})
bond_featurizer = BaseBondFeaturizer({
'he': lambda bond: [0 for _ in range(10)]
})加载数据集,rdkit mol对象转换为图对象
带有featurizer的mol_to_bigraph方法将rdkit mol对象转换为图对象。此外,smiles_to_bigraph方法可以将smiles转换为图。
train_mols = Chem.SDMolSupplier('solubility.train.sdf')
train_smi =[Chem.MolToSmiles(m) for m in train_mols]
train_sol = torch.tensor([float(mol.GetProp('SOL')) for mol in train_mols]).reshape(-1,1)
test_mols = Chem.SDMolSupplier('solubility.test.sdf')
test_smi = [Chem.MolToSmiles(m) for m in test_mols]
test_sol = torch.tensor([float(mol.GetProp('SOL')) for mol in test_mols]).reshape(-1,1)
train_graph =[mol_to_bigraph(mol,
node_featurizer=atom_featurizer,
edge_featurizer=bond_featurizer) for mol in train_mols]
test_graph =[mol_to_bigraph(mol,
node_featurizer=atom_featurizer,
edge_featurizer=bond_featurizer) for mol in test_mols]AttentivFp模型
并定义用于训练和测试的数据加载器。
model = AttentiveFPPredictor(node_feat_size=39,
edge_feat_size=10,
num_layers=2,
num_timesteps=2,
graph_feat_size=200,
n_tasks=1,
dropout=0.2)
#model = model.to('cuda:0')
train_loader = DataLoader(dataset=list(zip(train_smi, train_graph, train_sol)), batch_size=128, collate_fn=collate_molgraphs)
test_loader = DataLoader(dataset=list(zip(test_smi, test_graph, test_sol)), batch_size=128, collate_fn=collate_molgraphs)定义可视化函数
def drawmol(idx, dataset, timestep):
smiles, graph, _ = dataset[idx]
print(smiles)
bg = dgl.batch([graph])
atom_feats, bond_feats = bg.ndata['hv'], bg.edata['he']
if torch.cuda.is_available():
print('use cuda')
bg.to(torch.device('cuda:0'))
atom_feats = atom_feats.to('cuda:0')
bond_feats = bond_feats.to('cuda:0')
_, atom_weights = model(bg, atom_feats, bond_feats, get_node_weight=True)
assert timestep < len(atom_weights), 'Unexpected id for the readout round'
atom_weights = atom_weights[timestep]
min_value = torch.min(atom_weights)
max_value = torch.max(atom_weights)
atom_weights = (atom_weights - min_value) / (max_value - min_value)
norm = matplotlib.colors.Normalize(vmin=0, vmax=1.28)
cmap = cm.get_cmap('bwr')
plt_colors = cm.ScalarMappable(norm=norm, cmap=cmap)
atom_colors = {i: plt_colors.to_rgba(atom_weights[i].data.item()) for i in range(bg.number_of_nodes())}
mol = Chem.MolFromSmiles(smiles)
rdDepictor.Compute2DCoords(mol)
drawer = rdMolDraw2D.MolDraw2DSVG(280, 280)
drawer.SetFontSize(1)
op = drawer.drawOptions()
mol = rdMolDraw2D.PrepareMolForDrawing(mol)
drawer.DrawMolecule(mol, highlightAtoms=range(bg.number_of_nodes()),
highlightBonds=[],
highlightAtomColors=atom_colors)
drawer.FinishDrawing()
svg = drawer.GetDrawingText()
svg = svg.replace('svg:', '')
if torch.cuda.is_available():
atom_weights = atom_weights.to('cpu')
a = np.array([[0,1]])
plt.figure(figsize=(9, 1.5))
img = plt.imshow(a, cmap="bwr")
plt.gca().set_visible(False)
cax = plt.axes([0.1, 0.2, 0.8, 0.2])
plt.colorbar(orientation='horizontal', cax=cax)
plt.show()
return (Chem.MolFromSmiles(smiles), atom_weights.data.numpy(), svg)绘制测试数据集分子
该模型预测溶解度,颜色表示红色是溶解度的积极影响,蓝色是负面影响。
target = test_loader.dataset
for i in range(len(target))[:5]:
mol, aw, svg = drawmol(i, target, 0)
print(aw.min(), aw.max())
display(SVG(svg))
参考资料