Entangled Network Simulation

This repository contains C++ and MATLAB codes for simulating and visualizing the mechanics of entangled networks. For more details on the algorithm and implementation, please refer to our paper:

J. Huang, J. Liu, and S. Lin. Topological Mechanics of Entangled Networks. arXiv preprint arXiv:2509.17813. (2025)

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Environment

• Compiler: GCC 11
• Platform: Linux / macOS
• Dependencies: Standard C++ libraries and MATLAB (for plotting)

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Compile and Run

1. Compile

cd code_cpp
make

2. Run Simulation

./main 20 80 10 5.0 40 1e-2 100000 1e-1 1e-1 5 0.0 2 2 2 0 0.0 1e-3 0 0.5 100 1 1234

This command runs the simulation with the specified parameters. The computation typically takes a few minutes to complete, depending on the hardware configuration.

After the run finishes, the program will automatically generate:

• Log files (*.txt) containing runtime information and diagnostic data.
• Binary data files (*.bin) storing numerical results.

You can then proceed to the next step to visualize and analyze the results in MATLAB.

Example Input Parameters

Argument	Description	Example Value
num_layer	Number of layers	20
num_width	Number of nodes per layer	80
max_node_num	Maximum number of nodes	10
total_stretch	Total applied stretch	5.0
num_sampling_stretch	Number of sampled stretch points	40
error_tol	Error tolerance	1e-2
max_time_step	Maximum number of time steps	100000
dt_no_entangle	Time step (no entanglement)	1e-1
dt_entangle	Time step (entangled)	1e-1
num_decay_dt	Number of decay steps	5
rand_loc	Random location flag	0.0
unit_size_x	Unit size in x	2
unit_size_y	Unit size in y	2
num_cross_linker_in_unit	Number of crosslinkers per unit	2
is_random_cross_linker	Use random crosslinkers (0/1)	0
prob_cross_linker	Probability of crosslinker	0.0
error_tol_energy_stretch	Energy–stretch tolerance	1e-3
is_random_entangle_orientation	Random entanglement orientation (0/1)	0
prob_entangle_orientation	Probability of entanglement orientation	0.5
print_time_interval	Print interval (steps)	100
is_fracture	Enable fracture (0/1)	1
rand_seed	Random seed	1234

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Visualization

To generate plots from the simulation results:

cd code_matlab_plot
run main.m

This script will automatically produce several figures visualizing the networks in the undeformed and deformed states.

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Repository Structure

.
├── code_cpp/             # C++ source files and Makefile
│   ├── main.cpp
│   ├── ...
│   └── Makefile
├── code_matlab_plot/     # MATLAB plotting scripts
│   ├── main.m
│   └── ...
└── README.md             # This file

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Contact: For questions or feedback, please reach out to the authors via GitHub Issues or email (huangjt@udel.edu).