Ml forces

[marjanalbooyeh]

This pull request focuses on the implementation of machine learning models for coarse-graining simulations. The changes include adding new utility functions, creating a custom force class, defining a neural network model, and providing a tutorial notebook.

Changes:

• Introduced IsotropicCustomForce in flowermd/library/ml_forces.py to integrate a PyTorch model with the simulation framework.

• Defined LennardJonesNeighborModel and its configuration in flowermd/modules/coarse_graining_ML/isotropic_coarse_graining.py for predicting forces based on neighbor distances.

• Added functions adjust_periodic_boundary, find_neighbors, and neighbors_dr to flowermd/internal/box_neighbors_utils.py for handling periodic boundary conditions and neighbor calculations.

• Added a new Jupyter notebook tutorials/6-flowermd-ML-coarse-graining.ipynb to demonstrate the usage of the pre-trained machine learning model for coarse-graining simulations.