{"id":19489959,"url":"https://github.com/cchandre/vlasov1d","last_synced_at":"2026-04-08T21:31:59.237Z","repository":{"id":151252871,"uuid":"414668480","full_name":"cchandre/Vlasov1D","owner":"cchandre","description":"One-dimensional Vlasov-Poisson equation and its Hamiltonian fluid reductions","archived":false,"fork":false,"pushed_at":"2022-10-03T12:43:01.000Z","size":30845,"stargazers_count":2,"open_issues_count":0,"forks_count":0,"subscribers_count":1,"default_branch":"main","last_synced_at":"2025-08-16T17:42:42.030Z","etag":null,"topics":["fluid-simulation","fluid-solver","hamiltonian","hamiltonian-dynamics","livescript","mathematica","matlab","matlab-code","numpy","plasma-physics","python3","scipy","vlasov-equation"],"latest_commit_sha":null,"homepage":"","language":"Mathematica","has_issues":true,"has_wiki":null,"has_pages":null,"mirror_url":null,"source_name":null,"license":"bsd-2-clause","status":null,"scm":"git","pull_requests_enabled":true,"icon_url":"https://github.com/cchandre.png","metadata":{"files":{"readme":"README.md","changelog":null,"contributing":null,"funding":null,"license":"LICENSE","code_of_conduct":null,"threat_model":null,"audit":null,"citation":null,"codeowners":null,"security":null,"support":null,"governance":null,"roadmap":null,"authors":null,"dei":null,"publiccode":null,"codemeta":null}},"created_at":"2021-10-07T16:02:00.000Z","updated_at":"2023-04-17T08:39:09.000Z","dependencies_parsed_at":"2024-03-14T04:00:43.258Z","dependency_job_id":null,"html_url":"https://github.com/cchandre/Vlasov1D","commit_stats":null,"previous_names":[],"tags_count":0,"template":false,"template_full_name":null,"purl":"pkg:github/cchandre/Vlasov1D","repository_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/cchandre%2FVlasov1D","tags_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/cchandre%2FVlasov1D/tags","releases_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/cchandre%2FVlasov1D/releases","manifests_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/cchandre%2FVlasov1D/manifests","owner_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/owners/cchandre","download_url":"https://codeload.github.com/cchandre/Vlasov1D/tar.gz/refs/heads/main","sbom_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/cchandre%2FVlasov1D/sbom","scorecard":null,"host":{"name":"GitHub","url":"https://github.com","kind":"github","repositories_count":286080680,"owners_count":31575481,"icon_url":"https://github.com/github.png","version":null,"created_at":"2022-05-30T11:31:42.601Z","updated_at":"2026-04-08T14:31:17.711Z","status":"ssl_error","status_checked_at":"2026-04-08T14:31:17.202Z","response_time":54,"last_error":"SSL_connect returned=1 errno=0 peeraddr=140.82.121.5:443 state=error: unexpected eof while reading","robots_txt_status":"success","robots_txt_updated_at":"2025-07-24T06:49:26.215Z","robots_txt_url":"https://github.com/robots.txt","online":false,"can_crawl_api":true,"host_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub","repositories_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories","repository_names_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repository_names","owners_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/owners"}},"keywords":["fluid-simulation","fluid-solver","hamiltonian","hamiltonian-dynamics","livescript","mathematica","matlab","matlab-code","numpy","plasma-physics","python3","scipy","vlasov-equation"],"created_at":"2024-11-10T21:10:34.069Z","updated_at":"2026-04-08T21:31:59.220Z","avatar_url":"https://github.com/cchandre.png","language":"Mathematica","funding_links":[],"categories":[],"sub_categories":[],"readme":"# One-dimensional Vlasov-Poisson equation and its Hamiltonian fluid reductions\n\n- [`Vlasov1D_4field.mlx`](https://github.com/cchandre/Vlasov1D/blob/main/Vlasov1D_4field.mlx): MATLAB live script to compute and represent the series expansion of the explicit closure S\u003csub\u003e4\u003c/sub\u003e=S\u003csub\u003e4\u003c/sub\u003e(S\u003csub\u003e2\u003c/sub\u003e,S\u003csub\u003e3\u003c/sub\u003e) and S\u003csub\u003e5\u003c/sub\u003e=S\u003csub\u003e5\u003c/sub\u003e(S\u003csub\u003e2\u003c/sub\u003e,S\u003csub\u003e3\u003c/sub\u003e); also compute the series expansions of the three Casimir invariants C\u003csub\u003e1\u003c/sub\u003e, C\u003csub\u003e2\u003c/sub\u003e and C\u003csub\u003e3\u003c/sub\u003e\n- [`ParametricClosure4.nb`](https://github.com/cchandre/Vlasov1D/blob/main/ParametricClosure4.nb): Mathematica notebook to check and represent the parametric closure S\u003csub\u003e2\u003c/sub\u003e=S\u003csub\u003e2\u003c/sub\u003e(\u0026Gamma;\u003csub\u003e2\u003c/sub\u003e,\u0026Gamma;\u003csub\u003e3\u003c/sub\u003e), S\u003csub\u003e3\u003c/sub\u003e=S\u003csub\u003e3\u003c/sub\u003e(\u0026Gamma;\u003csub\u003e2\u003c/sub\u003e,\u0026Gamma;\u003csub\u003e3\u003c/sub\u003e),  S\u003csub\u003e4\u003c/sub\u003e=S\u003csub\u003e4\u003c/sub\u003e(\u0026Gamma;\u003csub\u003e2\u003c/sub\u003e,\u0026Gamma;\u003csub\u003e3\u003c/sub\u003e) and S\u003csub\u003e5\u003c/sub\u003e=S\u003csub\u003e5\u003c/sub\u003e(\u0026Gamma;\u003csub\u003e2\u003c/sub\u003e,\u0026Gamma;\u003csub\u003e3\u003c/sub\u003e)\n\n- `VP1D4f python code`\n  - [`VP1D4f_dict.py`](https://github.com/cchandre/Vlasov1D/blob/main/VP1D4f_dict.py): to be edited to change the parameters of the VP1D4f computation (see below for a dictionary of parameters)\n\n  - [`VP1D4f.py`](https://github.com/cchandre/Vlasov1D/blob/main/VP1D4f.py): contains the VP1D4f class and main functions (not to be edited)\n\n  - [`VP1D4f_modules.py`](https://github.com/cchandre/Vlasov1D/blob/main/VP1D4f_modules.py): contains the methods to run VP1D4f (not to be edited)\n  \n  - [`VP1D4f_AnalyzeData.m`](https://github.com/cchandre/Vlasov1D/blob/main/VP1D4f_AnalyzeData.m): MATLAB script to analyze the output saved in the `.mat` file  \n\n  - Once [`VP1D4f_dict.py`](https://github.com/cchandre/Vlasov1D/blob/main/VP1D4f_dict.py) has been edited with the relevant parameters, run the file as \n  ```sh\n  python3 VP1D4f.py\n  ```\n  or \n  ```sh\n  nohup python3 -u VP1D4f.py \u0026\u003eVP1D4f.out \u003c /dev/null \u0026\n  ```\n  The list of Python packages and their version are specified in [`modules_version.txt`](https://github.com/cchandre/Vlasov1D/blob/main/modules_version.txt)\n___\n##  Parameter dictionary for VP1D4f\n\n- *kappa*: double; value of \u0026kappa; defining the fluid reduction \n- *Tf*: double; duration of the integration (in units of *\u0026omega;\u003csub\u003ep\u003c/sub\u003e\u003csup\u003e-1\u003c/sup\u003e*)\n- *integrator_kinetic*: string ('position-Verlet', 'velocity-Verlet', 'Forest-Ruth', 'PEFRL', 'BM4', 'BM6'); choice of solver for the integration of the Vlasov equation\n   - 'Forest-Ruth' from [Forest, Ruth, Physica D 43, 105 (1990)](https://doi.org/10.1016/0167-2789(90)90019-L)\n   - 'PEFRL' from [Omelyan, Mryglod, Folk, Comput. Phys. Commun. 146, 188 (2002)](https://doi.org/10.1016/S0010-4655(02)00451-4)\n   - 'BM4' and 'BM6' refer respectively to BM\u003csub\u003e6\u003c/sub\u003e4 and BM\u003csub\u003e10\u003c/sub\u003e6 from [Blanes, Moan, J. Comput. Appl. Math. 142, 313 (2002)](https://doi.org/10.1016/S0377-0427(01)00492-7)\n- *nsteps*: integer; number of steps in one period of plasma oscillations (1/*\u0026omega;\u003csub\u003ep\u003c/sub\u003e\u003csup\u003e*) for the integration of the Vlasov equation\n- *integrator_fluid*: string ('RK45', ‘RK23’, ‘DOP853’, ‘BDF’, ‘LSODA’); choice of solver for the integration of the fluid equation (see [ivp_solve](https://docs.scipy.org/doc/scipy/reference/generated/scipy.integrate.solve_ivp.html) for more details)\n- *precision*: double; numerical precision of the integrator for the fluid equations; threshold for the Fourier transforms\n- *n_casimirs*: integer; number of Casimir invariants to be monitored \n\n- *Lx*: double; the *x*-axis is (-*Lx*, *Lx*)\n- *Lv*: double; the *v*-axis is (-*Lv*, *Lv*)\n- *Nx*: integer; number of points in *x* to represent the field variables\n- *Nv*: integer; number of points in *v* to represent the field variables\n- *f_init*: lambda function; initial distribution *f*(*x*,*v*,*t*=0)\n  \n- *output_var*: string in ['E', 'rho', 'u', 'P', 'q']; variable to be saved in a `.mat` file\n- *output_modes*: integer or string in ['all', 'real']; number of Fourier modes of the variable to be saved in the `.mat` file; if 'all', all Fourier modes are saved; if 'real', the variable is saved in real space; use the MATLAB script [`VP1D4f_AnalyzeData.m`](https://github.com/cchandre/Vlasov1D/blob/main/VP1D4f_AnalyzeData.m) to plot the output \n\n- *Kinetic*: list of strings in ['Compute', 'Plot', 'Save']; list of instructions for the Vlasov-Poisson simulation; if contains 'Save', the results are saved in a `.mat` file\n- *Fluid*: list of strings in ['Compute', 'Plot', 'Save']; list of instructions for the fluid simulation; if contains 'Save', the results are saved in a `.mat` file\n\n- *darkmode*: boolean; if True, plots are done in dark mode\n\n---\nReference: C. Chandre, B.A. Shadwick, *Four-field Hamiltonian fluid closures of the one-dimensional Vlasov-Poisson equation*, [Physics of Plasmas](https://aip.scitation.org/journal/php) 29, 102101 (2022); [arXiv:2206.06850](https://arxiv.org/abs/2206.06850)\n\n```bibtex\n@article{chandre2022,\n         title = {Four-field Hamiltonian fluid closures of the one-dimensional Vlasov-Poisson equation},\n         author = {Chandre, C. and Shadwick, B.A.},\n         journal = {Physics of Plasmas},\n         volume = {29},\n         number = {10},\n         pages = {102101},\n         year = {2022},\n         doi = {10.1063/5.0102418},\n         URL = {https://doi.org/10.1063/5.0102418}\n}\n```\n\nFor more information: \u003ccristel.chandre@cnrs.fr\u003e\n\n\u003cp align=\"center\"\u003e\n  \u003cimg src=\"https://github.com/cchandre/Vlasov1D/blob/main/fig_VP1D4f.png\" alt=\"Example\" width=\"400\"/\u003e\n\u003c/p\u003e\n","project_url":"https://awesome.ecosyste.ms/api/v1/projects/github.com%2Fcchandre%2Fvlasov1d","html_url":"https://awesome.ecosyste.ms/projects/github.com%2Fcchandre%2Fvlasov1d","lists_url":"https://awesome.ecosyste.ms/api/v1/projects/github.com%2Fcchandre%2Fvlasov1d/lists"}