README.md

October 8, 2025 ยท View on GitHub

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Deep learning for molecular discovery with a simple sklearn-style interface


torch-molecule is a package that facilitates molecular discovery through deep learning, featuring a user-friendly, sklearn-style interface. It includes model checkpoints for efficient deployment and benchmarking across a range of molecular tasks. The package focuses on three main components: Predictive Models, Generative Models, and Representation Models, which make molecular AI models easy to implement and deploy.

scikit-learn vs torch-molecule comparison

See the List of Supported Models section for all available models.

Installation

  1. Create a Conda environment:

    conda create --name torch_molecule python=3.11.7
    conda activate torch_molecule
    
  2. Install using pip:

    pip install torch-molecule
    
  3. Install from source for the latest version:

    Clone the repository:

    git clone https://github.com/liugangcode/torch-molecule
    cd torch-molecule
    

    Install:

    pip install .
    

Additional Packages

ModelRequired Packages
HFPretrainedMolecularEncodertransformers
BFGNNMolecularPredictortorch-scatter
GRINMolecularPredictortorch-scatter
GRINMolecularPredictor (if enable repetition_augmentation=True)CombineMols

For models that require torch-scatter: Install using the following command: pip install torch-scatter -f https://data.pyg.org/whl/torch-${TORCH}+${CUDA}.html, e.g.,

pip install torch-scatter -f https://data.pyg.org/whl/torch-2.7.1+cu128.html

For models that require transformers: pip install transformers

Usage

More examples can be found in the examples and tests folders.

torch-molecule supports applications in broad domains from chemistry, biology, to materials science. To get started, you can load prepared datasets from torch_molecule.datasets (updated after v0.1.3):

DatasetDescriptionFunction
qm9Quantum chemical properties (DFT level)load_qm9
chembl2kBioactive molecules with drug-like propertiesload_chembl2k
broad6kBioactive molecules with drug-like propertiesload_broad6k
toxcastToxicity of chemical compoundsload_toxcast
admetChemical absorption, distribution, metabolism, excretion, and toxicityload_admet
gaspermSix gas permeability properties for polymeric materialsload_gasperm
zinc250kA common subset of ZINC dataset, which does not have labels and could be used for unconditional generation or virtual screeningload_zinc250k
from torch_molecule.datasets import load_qm9

# local_dir is the local path where the dataset will be saved
molecular_data = load_qm9(local_dir='torchmol_data')
smiles_list, property_np_array = molecular_data.data, molecular_data.target

# len(smiles_list): 133885
# Property array shape: (133885, 1)

# load_qm9 returns the target "gap" by default, but you can adjust it by passing new target_cols
target_cols = ['homo', 'lumo', 'gap']
molecular_data = load_qm9(local_dir='torchmol_data', target_cols=target_cols)
smiles_list, property_np_array = molecular_data.data, molecular_data.target

# the target could be None if loading an unlabeled dataset
from torch_molecule.datasets import load_zinc250k
molecular_data = load_zinc250k(local_dir='torchmol_data')
smiles_list = molecular_data.data
assert molecular_data.target is None

(We are actively adding more datasets. We welcome your suggestions and contributions on your datasets!)

Fit a Model

After preparing the dataset, we can easily fit a model similar to how we use sklearn (actually, the coding is even simpler than sklearn, as we still need to do feature engineering in sklearn to convert molecule SMILES into vectors):

from torch_molecule import GREAMolecularPredictor

split = int(0.8 * len(smiles_list))

grea = GREAMolecularPredictor(
    num_task=num_task,
    task_type="regression",
    evaluate_higher_better=False,
    verbose="progress_bar" #or "print_statement" recommended for jupyter notebooks, or "none"
)

# Fit with automatic hyperparameter tuning with 10 attempts, or implement .fit() with the default/manual hyperparameters
grea.autofit(
    X_train=smiles_list[:split],
    y_train=property_np_array[:split],
    X_val=smiles_list[split:],
    y_val=property_np_array[split:],
    n_trials=10,
)

Checkpoints

torch-molecule provides checkpoint functions that can be interacted with on Hugging Face:

from torch_molecule import GREAMolecularPredictor

repo_id = "user/repo_id"  # replace with your own Hugging Face username and repo_id

# Save the trained model to Hugging Face
grea.save_to_hf(
    repo_id=repo_id,
    task_id="qm9_grea",
    commit_message="Upload qm9_grea",
    private=False
)

# Load a pretrained checkpoint from Hugging Face
model = GREAMolecularPredictor()
model.load_from_hf(repo_id=repo_id, local_cache=f"{model_dir}/GREA_{task_name}.pt")

# Adjust model parameters and make predictions
model.set_params(verbose='none')
predictions = model.predict(smiles_list)

Or you can save the model to a local path:

grea.save_to_local("qm9_grea.pt")

new_model = GREAMolecularPredictor()
new_model.load_from_local("qm9_grea.pt")

List of Supported Models

Predictive Models

ModelReference
GRINLearning Repetition-Invariant Representations for Polymer Informatics. NeurIPS 2025.
BFGNNGraph neural networks extrapolate out-of-distribution for shortest paths. March 2025
SGIRSemi-Supervised Graph Imbalanced Regression. KDD 2023
GREAGraph Rationalization with Environment-based Augmentations. KDD 2022
DIRDiscovering Invariant Rationales for Graph Neural Networks. ICLR 2022
SSRSizeShiftReg: a Regularization Method for Improving Size-Generalization in Graph Neural Networks. NeurIPS 2022
IRMInvariant Risk Minimization (2019)
RPGNNRelational Pooling for Graph Representations. ICML 2019
GNNsGraph Convolutional Networks. ICLR 2017 and Graph Isomorphism Network. ICLR 2019
Transformer (SMILES)Transformer (Attention is All You Need. NeurIPS 2017) based on SMILES strings
LSTM (SMILES)Long short-term memory (Neural Computation 1997) based on SMILES strings

Generative Models

ModelReference
DeFoGDeFoG: Discrete Flow Matching for Graph Generation. ICML 2025
Graph DiTGraph Diffusion Transformers for Multi-Conditional Molecular Generation. NeurIPS 2024
DiGressDiGress: Discrete Denoising Diffusion for Graph Generation. ICLR 2023
GDSSScore-based Generative Modeling of Graphs via the System of Stochastic Differential Equations. ICML 2022
MolGPTMolGPT: Molecular Generation Using a Transformer-Decoder Model. Journal of Chemical Information and Modeling 2021
JTVAEJunction Tree Variational Autoencoder for Molecular Graph Generation. ICML 2018.
GraphGAA Graph-Based Genetic Algorithm and Its Application to the Multiobjective Evolution of Median Molecules. Journal of Chemical Information and Computer Sciences 2004
LSTM (SMILES)Long short-term memory (Neural Computation 1997) based on SMILES strings

Representation Models

ModelReference
MoAMaMotif-aware Attribute Masking for Molecular Graph Pre-training. LoG 2024
GraphMAEGraphMAE: Self-Supervised Masked Graph Autoencoders. KDD 2022
AttrMaskingStrategies for Pre-training Graph Neural Networks. ICLR 2020
ContextPredStrategies for Pre-training Graph Neural Networks. ICLR 2020
EdgePredStrategies for Pre-training Graph Neural Networks. ICLR 2020
InfoGraphInfoGraph: Unsupervised and Semi-supervised Graph-Level Representation Learning via Mutual Information Maximization. ICLR 2020
SupervisedSupervised pretraining
PretrainedGPT2-ZINC-87M: GPT-2 based model (87M parameters) pretrained on ZINC dataset with ~480M SMILES strings.
RoBERTa-ZINC-480M: RoBERTa based model (102M parameters) pretrained on ZINC dataset with ~480M SMILES strings.
UniKi/bert-base-smiles: BERT model pretrained on SMILES strings.
ChemBERTa-zinc-base-v1: RoBERTa model pretrained on ZINC dataset with ~100k SMILES strings.
ChemBERTa series: Available in multiple sizes and training objectives (MLM/MTR). ChemBERTa-5M-MLM, ChemBERTa-5M-MTR, ChemBERTa-10M-MLM, ChemBERTa-10M-MTR, ChemBERTa-77M-MLM, ChemBERTa-77M-MTR.
ChemGPT series: GPT-Neo based models pretrained on PubChem10M dataset with SELFIES strings. ChemGPT-1.2B, ChemGPT-4.7B, ChemGPT-19B.

Acknowledgements

The project template was adapted from https://github.com/lwaekfjlk/python-project-template. We thank the authors for their contribution to the open-source community.