The Jupyter notebook file chrsinvt.ipynb contains all codes necessary to reproduce the study published in the article "A Characteristic-based constitutive law for dispersed fibers". The notebook was created on SageMathCloud (SMC) (http://cloud.sagemath.com), which is the best place to run and modify the current code.
To run the code on SMC, simply copy this notebook over to SMC. Open the notebook and set the jupyter notebook kernel to SageMath. All source codes are written in Python and the computation engine is SageMath. Here is a tutorial for SageMath: http://doc.sagemath.org/html/en/tutorial/index.html