853 lines
74 KiB
HTML
853 lines
74 KiB
HTML
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<title>fix ave/grid command — LAMMPS documentation</title>
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<link rel="next" title="fix ave/histo command" href="fix_ave_histo.html" />
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<div class="lammps_version">Version: <b>19 Nov 2024</b></div>
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<p class="caption" role="heading"><span class="caption-text">User Guide</span></p>
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<li class="toctree-l1"><a class="reference internal" href="Intro.html">1. Introduction</a></li>
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<li class="toctree-l1"><a class="reference internal" href="Install.html">2. Install LAMMPS</a></li>
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<li class="toctree-l1"><a class="reference internal" href="Build.html">3. Build LAMMPS</a></li>
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<li class="toctree-l1"><a class="reference internal" href="Run_head.html">4. Run LAMMPS</a></li>
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<li class="toctree-l1"><a class="reference internal" href="Commands.html">5. Commands</a></li>
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<li class="toctree-l1"><a class="reference internal" href="Packages.html">6. Optional packages</a></li>
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<li class="toctree-l1"><a class="reference internal" href="Speed.html">7. Accelerate performance</a></li>
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<li class="toctree-l1"><a class="reference internal" href="Howto.html">8. Howto discussions</a></li>
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<li class="toctree-l1"><a class="reference internal" href="Examples.html">9. Example scripts</a></li>
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<li class="toctree-l1"><a class="reference internal" href="Tools.html">10. Auxiliary tools</a></li>
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<li class="toctree-l1"><a class="reference internal" href="Errors.html">11. Errors</a></li>
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<p class="caption" role="heading"><span class="caption-text">Programmer Guide</span></p>
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<ul>
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<li class="toctree-l1"><a class="reference internal" href="Library.html">1. LAMMPS Library Interfaces</a></li>
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<li class="toctree-l1"><a class="reference internal" href="Python_head.html">2. Use Python with LAMMPS</a></li>
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<li class="toctree-l1"><a class="reference internal" href="Modify.html">3. Modifying & extending LAMMPS</a></li>
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<li class="toctree-l1"><a class="reference internal" href="Developer.html">4. Information for Developers</a></li>
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</ul>
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<p class="caption" role="heading"><span class="caption-text">Command Reference</span></p>
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<ul class="current">
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<li class="toctree-l1"><a class="reference internal" href="commands_list.html">Commands</a></li>
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<li class="toctree-l1 current"><a class="reference internal" href="fixes.html">Fix Styles</a><ul class="current">
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<li class="toctree-l2"><a class="reference internal" href="fix_accelerate_cos.html">fix accelerate/cos command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_acks2_reaxff.html">fix acks2/reaxff command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_adapt.html">fix adapt command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_adapt_fep.html">fix adapt/fep command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_add_heat.html">fix add/heat command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_addforce.html">fix addforce command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_addtorque.html">fix addtorque command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_alchemy.html">fix alchemy command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_amoeba_bitorsion.html">fix amoeba/bitorsion command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_amoeba_pitorsion.html">fix amoeba/pitorsion command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_append_atoms.html">fix append/atoms command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_atc.html">fix atc command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_atom_swap.html">fix atom/swap command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_ave_atom.html">fix ave/atom command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_ave_chunk.html">fix ave/chunk command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_ave_correlate.html">fix ave/correlate command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_ave_correlate_long.html">fix ave/correlate/long command</a></li>
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<li class="toctree-l2 current"><a class="current reference internal" href="#">fix ave/grid command</a><ul>
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<li class="toctree-l3"><a class="reference internal" href="#syntax">Syntax</a></li>
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<li class="toctree-l3"><a class="reference internal" href="#examples">Examples</a></li>
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<li class="toctree-l3"><a class="reference internal" href="#description">Description</a></li>
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<li class="toctree-l3"><a class="reference internal" href="#restart-fix-modify-output-run-start-stop-minimize-info">Restart, fix_modify, output, run start/stop, minimize info</a></li>
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<li class="toctree-l3"><a class="reference internal" href="#restrictions">Restrictions</a></li>
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<li class="toctree-l3"><a class="reference internal" href="#related-commands">Related commands</a></li>
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<li class="toctree-l3"><a class="reference internal" href="#default">Default</a></li>
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</ul>
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</li>
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<li class="toctree-l2"><a class="reference internal" href="fix_ave_histo.html">fix ave/histo command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_ave_histo.html#fix-ave-histo-weight-command">fix ave/histo/weight command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_ave_spatial.html">fix ave/spatial command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_ave_spatial_sphere.html">fix ave/spatial/sphere command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_ave_time.html">fix ave/time command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_aveforce.html">fix aveforce command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_balance.html">fix balance command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_bocs.html">fix bocs command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_bond_break.html">fix bond/break command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_bond_create.html">fix bond/create command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_bond_create.html#fix-bond-create-angle-command">fix bond/create/angle command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_bond_react.html">fix bond/react command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_bond_swap.html">fix bond/swap command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_box_relax.html">fix box/relax command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_brownian.html">fix brownian command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_brownian.html#fix-brownian-sphere-command">fix brownian/sphere command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_brownian.html#fix-brownian-asphere-command">fix brownian/asphere command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_charge_regulation.html">fix charge/regulation command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_cmap.html">fix cmap command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_colvars.html">fix colvars command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_controller.html">fix controller command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_damping_cundall.html">fix damping/cundall command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_deform.html">fix deform command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_deform_pressure.html">fix deform/pressure command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_deposit.html">fix deposit command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_dpd_energy.html">fix dpd/energy command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_dpd_source.html">fix edpd/source command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_dpd_source.html#fix-tdpd-source-command">fix tdpd/source command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_drag.html">fix drag command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_drude.html">fix drude command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_drude_transform.html">fix drude/transform/direct command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_drude_transform.html#fix-drude-transform-inverse-command">fix drude/transform/inverse command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_dt_reset.html">fix dt/reset command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_efield.html">fix efield command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_efield.html#fix-efield-tip4p-command">fix efield/tip4p command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_ehex.html">fix ehex command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_electrode.html">fix electrode/conp command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_electrode.html#fix-electrode-conq-command">fix electrode/conq command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_electrode.html#fix-electrode-thermo-command">fix electrode/thermo command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_electron_stopping.html">fix electron/stopping command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_electron_stopping.html#fix-electron-stopping-fit-command">fix electron/stopping/fit command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_enforce2d.html">fix enforce2d command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_eos_cv.html">fix eos/cv command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_eos_table.html">fix eos/table command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_eos_table_rx.html">fix eos/table/rx command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_evaporate.html">fix evaporate command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_external.html">fix external command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_ffl.html">fix ffl command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_filter_corotate.html">fix filter/corotate command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_flow_gauss.html">fix flow/gauss command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_freeze.html">fix freeze command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_gcmc.html">fix gcmc command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_gld.html">fix gld command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_gle.html">fix gle command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_gravity.html">fix gravity command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_grem.html">fix grem command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_halt.html">fix halt command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_heat.html">fix heat command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_heat_flow.html">fix heat/flow command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_hyper_global.html">fix hyper/global command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_hyper_local.html">fix hyper/local command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_imd.html">fix imd command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_indent.html">fix indent command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_ipi.html">fix ipi command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_langevin.html">fix langevin command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_langevin_drude.html">fix langevin/drude command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_langevin_eff.html">fix langevin/eff command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_langevin_spin.html">fix langevin/spin command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_lb_fluid.html">fix lb/fluid command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_lb_momentum.html">fix lb/momentum command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_lb_viscous.html">fix lb/viscous command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_lineforce.html">fix lineforce command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_manifoldforce.html">fix manifoldforce command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_mdi_qm.html">fix mdi/qm command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_mdi_qmmm.html">fix mdi/qmmm command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_meso_move.html">fix meso/move command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_mol_swap.html">fix mol/swap command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_momentum.html">fix momentum command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_momentum.html#fix-momentum-chunk-command">fix momentum/chunk command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_move.html">fix move command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_msst.html">fix msst command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_mvv_dpd.html">fix mvv/dpd command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_mvv_dpd.html#fix-mvv-edpd-command">fix mvv/edpd command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_mvv_dpd.html#fix-mvv-tdpd-command">fix mvv/tdpd command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_neb.html">fix neb command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_neb_spin.html">fix neb/spin command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_nh.html">fix nvt command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_nh.html#fix-npt-command">fix npt command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_nh.html#fix-nph-command">fix nph command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_nh_eff.html">fix nvt/eff command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_nh_eff.html#fix-npt-eff-command">fix npt/eff command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_nh_eff.html#fix-nph-eff-command">fix nph/eff command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_nh_uef.html">fix nvt/uef command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_nh_uef.html#fix-npt-uef-command">fix npt/uef command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_nonaffine_displacement.html">fix nonaffine/displacement command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_nph_asphere.html">fix nph/asphere command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_nph_body.html">fix nph/body command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_nph_sphere.html">fix nph/sphere command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_nphug.html">fix nphug command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_npt_asphere.html">fix npt/asphere command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_npt_body.html">fix npt/body command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_npt_cauchy.html">fix npt/cauchy command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_npt_sphere.html">fix npt/sphere command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_numdiff.html">fix numdiff command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_numdiff_virial.html">fix numdiff/virial command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_nve.html">fix nve command</a></li>
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|
<li class="toctree-l2"><a class="reference internal" href="fix_nve_asphere.html">fix nve/asphere command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_nve_asphere_noforce.html">fix nve/asphere/noforce command</a></li>
|
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<li class="toctree-l2"><a class="reference internal" href="fix_nve_awpmd.html">fix nve/awpmd command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_nve_body.html">fix nve/body command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_nve_bpm_sphere.html">fix nve/bpm/sphere command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_nve_dot.html">fix nve/dot command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_nve_dotc_langevin.html">fix nve/dotc/langevin command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_nve_eff.html">fix nve/eff command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_nve_limit.html">fix nve/limit command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_nve_line.html">fix nve/line command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_nve_manifold_rattle.html">fix nve/manifold/rattle command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_nve_noforce.html">fix nve/noforce command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_nve_sphere.html">fix nve/sphere command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_nve_spin.html">fix nve/spin command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_nve_tri.html">fix nve/tri command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_nvk.html">fix nvk command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_nvt_asphere.html">fix nvt/asphere command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_nvt_body.html">fix nvt/body command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_nvt_manifold_rattle.html">fix nvt/manifold/rattle command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_nvt_sllod.html">fix nvt/sllod command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_nvt_sllod_eff.html">fix nvt/sllod/eff command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_nvt_sphere.html">fix nvt/sphere command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_oneway.html">fix oneway command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_orient.html">fix orient/fcc command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_orient.html#fix-orient-bcc-command">fix orient/bcc command</a></li>
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|
<li class="toctree-l2"><a class="reference internal" href="fix_orient_eco.html">fix orient/eco command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_pafi.html">fix pafi command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_pair.html">fix pair command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_phonon.html">fix phonon command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_pimd.html">fix pimd/langevin command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_pimd.html#fix-pimd-nvt-command">fix pimd/nvt command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_pimdb.html">fix pimdb/langevin command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_pimdb.html#fix-pimdb-nvt-command">fix pimdb/nvt command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_planeforce.html">fix planeforce command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_plumed.html">fix plumed command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_poems.html">fix poems command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_polarize.html">fix polarize/bem/gmres command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_polarize.html#fix-polarize-bem-icc-command">fix polarize/bem/icc command</a></li>
|
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<li class="toctree-l2"><a class="reference internal" href="fix_polarize.html#fix-polarize-functional-command">fix polarize/functional command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_pour.html">fix pour command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_precession_spin.html">fix precession/spin command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_press_berendsen.html">fix press/berendsen command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_press_langevin.html">fix press/langevin command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_print.html">fix print command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_propel_self.html">fix propel/self command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_property_atom.html">fix property/atom command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_python_invoke.html">fix python/invoke command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_python_move.html">fix python/move command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_qbmsst.html">fix qbmsst command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_qeq.html">fix qeq/point command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_qeq.html#fix-qeq-shielded-command">fix qeq/shielded command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_qeq.html#fix-qeq-slater-command">fix qeq/slater command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_qeq.html#fix-qeq-ctip-command">fix qeq/ctip command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_qeq.html#fix-qeq-dynamic-command">fix qeq/dynamic command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_qeq.html#fix-qeq-fire-command">fix qeq/fire command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_qeq_comb.html">fix qeq/comb command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_qeq_reaxff.html">fix qeq/reaxff command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_qmmm.html">fix qmmm command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_qtb.html">fix qtb command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_qtpie_reaxff.html">fix qtpie/reaxff command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_reaxff_bonds.html">fix reaxff/bonds command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_reaxff_species.html">fix reaxff/species command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_recenter.html">fix recenter command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_restrain.html">fix restrain command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_rheo.html">fix rheo command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_rheo_oxidation.html">fix rheo/oxidation command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_rheo_pressure.html">fix rheo/pressure command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_rheo_thermal.html">fix rheo/thermal command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_rheo_viscosity.html">fix rheo/viscosity command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_rhok.html">fix rhok command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_rigid.html">fix rigid command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_rigid.html#fix-rigid-nve-command">fix rigid/nve command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_rigid.html#fix-rigid-nvt-command">fix rigid/nvt command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_rigid.html#fix-rigid-npt-command">fix rigid/npt command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_rigid.html#fix-rigid-nph-command">fix rigid/nph command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_rigid.html#fix-rigid-small-command">fix rigid/small command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_rigid.html#fix-rigid-nve-small-command">fix rigid/nve/small command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_rigid.html#fix-rigid-nvt-small-command">fix rigid/nvt/small command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_rigid.html#fix-rigid-npt-small-command">fix rigid/npt/small command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_rigid.html#fix-rigid-nph-small-command">fix rigid/nph/small command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_rigid_meso.html">fix rigid/meso command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_rx.html">fix rx command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_saed_vtk.html">fix saed/vtk command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_setforce.html">fix setforce command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_setforce.html#fix-setforce-spin-command">fix setforce/spin command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_sgcmc.html">fix sgcmc command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_shake.html">fix shake command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_shake.html#fix-rattle-command">fix rattle command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_shardlow.html">fix shardlow command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_smd.html">fix smd command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_smd_adjust_dt.html">fix smd/adjust_dt command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_smd_integrate_tlsph.html">fix smd/integrate_tlsph command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_smd_integrate_ulsph.html">fix smd/integrate_ulsph command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_smd_move_triangulated_surface.html">fix smd/move_tri_surf command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_smd_setvel.html">fix smd/setvel command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_smd_wall_surface.html">fix smd/wall_surface command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_sph.html">fix sph command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_sph_stationary.html">fix sph/stationary command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_spring.html">fix spring command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_spring_chunk.html">fix spring/chunk command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_spring_rg.html">fix spring/rg command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_spring_self.html">fix spring/self command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_srd.html">fix srd command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_store_force.html">fix store/force command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_store_state.html">fix store/state command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_temp_berendsen.html">fix temp/berendsen command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_temp_csvr.html">fix temp/csvr command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_temp_csvr.html#fix-temp-csld-command">fix temp/csld command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_temp_rescale.html">fix temp/rescale command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_temp_rescale_eff.html">fix temp/rescale/eff command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_tfmc.html">fix tfmc command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_tgnh_drude.html">fix tgnvt/drude command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_tgnh_drude.html#fix-tgnpt-drude-command">fix tgnpt/drude command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_thermal_conductivity.html">fix thermal/conductivity command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_ti_spring.html">fix ti/spring command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_tmd.html">fix tmd command</a></li>
|
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<li class="toctree-l2"><a class="reference internal" href="fix_ttm.html">fix ttm command</a></li>
|
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<li class="toctree-l2"><a class="reference internal" href="fix_ttm.html#fix-ttm-grid-command">fix ttm/grid command</a></li>
|
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<li class="toctree-l2"><a class="reference internal" href="fix_ttm.html#fix-ttm-mod-command">fix ttm/mod command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_tune_kspace.html">fix tune/kspace command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_vector.html">fix vector command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_viscosity.html">fix viscosity command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_viscous.html">fix viscous command</a></li>
|
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<li class="toctree-l2"><a class="reference internal" href="fix_viscous_sphere.html">fix viscous/sphere command</a></li>
|
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<li class="toctree-l2"><a class="reference internal" href="fix_wall.html">fix wall/lj93 command</a></li>
|
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<li class="toctree-l2"><a class="reference internal" href="fix_wall.html#fix-wall-lj126-command">fix wall/lj126 command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_wall.html#fix-wall-lj1043-command">fix wall/lj1043 command</a></li>
|
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<li class="toctree-l2"><a class="reference internal" href="fix_wall.html#fix-wall-colloid-command">fix wall/colloid command</a></li>
|
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<li class="toctree-l2"><a class="reference internal" href="fix_wall.html#fix-wall-harmonic-command">fix wall/harmonic command</a></li>
|
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<li class="toctree-l2"><a class="reference internal" href="fix_wall.html#fix-wall-lepton-command">fix wall/lepton command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_wall.html#fix-wall-morse-command">fix wall/morse command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_wall.html#fix-wall-table-command">fix wall/table command</a></li>
|
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<li class="toctree-l2"><a class="reference internal" href="fix_wall_body_polygon.html">fix wall/body/polygon command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_wall_body_polyhedron.html">fix wall/body/polyhedron command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_wall_ees.html">fix wall/ees command</a></li>
|
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<li class="toctree-l2"><a class="reference internal" href="fix_wall_ees.html#fix-wall-region-ees-command">fix wall/region/ees command</a></li>
|
|
<li class="toctree-l2"><a class="reference internal" href="fix_wall_flow.html">fix wall/flow command</a></li>
|
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<li class="toctree-l2"><a class="reference internal" href="fix_wall_gran.html">fix wall/gran command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_wall_gran_region.html">fix wall/gran/region command</a></li>
|
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<li class="toctree-l2"><a class="reference internal" href="fix_wall_piston.html">fix wall/piston command</a></li>
|
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<li class="toctree-l2"><a class="reference internal" href="fix_wall_reflect.html">fix wall/reflect command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_wall_reflect_stochastic.html">fix wall/reflect/stochastic command</a></li>
|
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<li class="toctree-l2"><a class="reference internal" href="fix_wall_region.html">fix wall/region command</a></li>
|
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<li class="toctree-l2"><a class="reference internal" href="fix_wall_srd.html">fix wall/srd command</a></li>
|
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<li class="toctree-l2"><a class="reference internal" href="fix_widom.html">fix widom command</a></li>
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</ul>
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</li>
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<li class="toctree-l1"><a class="reference internal" href="computes.html">Compute Styles</a></li>
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<li class="toctree-l1"><a class="reference internal" href="pairs.html">Pair Styles</a></li>
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<li class="toctree-l1"><a class="reference internal" href="bonds.html">Bond Styles</a></li>
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<li class="toctree-l1"><a class="reference internal" href="angles.html">Angle Styles</a></li>
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<li class="toctree-l1"><a class="reference internal" href="dihedrals.html">Dihedral Styles</a></li>
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<li class="toctree-l1"><a class="reference internal" href="impropers.html">Improper Styles</a></li>
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<li class="toctree-l1"><a class="reference internal" href="dumps.html">Dump Styles</a></li>
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<li class="toctree-l1"><a class="reference internal" href="fix_modify_atc_commands.html">fix_modify AtC commands</a></li>
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<li class="toctree-l1"><a class="reference internal" href="Bibliography.html">Bibliography</a></li>
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</ul>
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<li class="breadcrumb-item active">fix ave/grid command</li>
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<a href="fix_ave_histo.html" class="btn btn-neutral float-right" title="fix ave/histo command" accesskey="n">Next <span class="fa fa-arrow-circle-right" aria-hidden="true"></span></a>
|
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</div>
|
|
<hr/>
|
|
</div>
|
|
<div role="main" class="document" itemscope="itemscope" itemtype="http://schema.org/Article">
|
|
<div itemprop="articleBody">
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|
|
|
<p><span class="math notranslate nohighlight">\(\renewcommand{\AA}{\text{Å}}\)</span></p>
|
|
<section id="fix-ave-grid-command">
|
|
<span id="index-0"></span><h1>fix ave/grid command<a class="headerlink" href="#fix-ave-grid-command" title="Link to this heading"></a></h1>
|
|
<section id="syntax">
|
|
<h2>Syntax<a class="headerlink" href="#syntax" title="Link to this heading"></a></h2>
|
|
<div class="highlight-LAMMPS notranslate"><div class="highlight"><pre><span></span><span class="k">fix </span><span class="nv nv-Identifier">ID</span><span class="w"> </span><span class="nv nv-Identifier">group-ID</span><span class="w"> </span><span class="n">ave</span><span class="o">/</span><span class="n">grid</span><span class="w"> </span><span class="n">Nevery</span><span class="w"> </span><span class="n">Nrepeat</span><span class="w"> </span><span class="n">Nfreq</span><span class="w"> </span><span class="n">Nx</span><span class="w"> </span><span class="n">Ny</span><span class="w"> </span><span class="n">Nz</span><span class="w"> </span><span class="n">value1</span><span class="w"> </span><span class="n">value2</span><span class="w"> </span><span class="n">...</span><span class="w"> </span><span class="n">keyword</span><span class="w"> </span><span class="n">args</span><span class="w"> </span><span class="n">...</span>
|
|
</pre></div>
|
|
</div>
|
|
<ul>
|
|
<li><p>ID, group-ID are documented in <a class="reference internal" href="fix.html"><span class="doc">fix</span></a> command</p></li>
|
|
<li><p>ave/grid = style name of this fix command</p></li>
|
|
<li><p>Nevery = use input values every this many timesteps</p></li>
|
|
<li><p>Nrepeat = # of times to use input values for calculating averages</p></li>
|
|
<li><p>Nfreq = calculate averages every this many timesteps</p></li>
|
|
<li><p>Nx, Ny, Nz = grid size in each dimension</p></li>
|
|
<li><p>one or more per-atom or per-grid input values can be listed</p></li>
|
|
<li><p>per-atom value = vx, vy, vz, fx, fy, fz, density/mass, density/number, mass, temp, c_ID, c_ID[I], f_ID, f_ID[I], v_name</p>
|
|
<div class="highlight-none notranslate"><div class="highlight"><pre><span></span>vx,vy,vz,fx,fy,fz,mass = atom attribute (velocity, force component, mass)
|
|
density/number, density/mass = number or mass density (per volume)
|
|
temp = temperature
|
|
c_ID = per-atom vector calculated by a compute with ID
|
|
c_ID[I] = Ith column of per-atom array calculated by a compute with ID, I can include wildcard (see below)
|
|
f_ID = per-atom vector calculated by a fix with ID
|
|
f_ID[I] = Ith column of per-atom array calculated by a fix with ID, I can include wildcard (see below)
|
|
v_name = per-atom vector calculated by an atom-style variable with name
|
|
</pre></div>
|
|
</div>
|
|
</li>
|
|
<li><p>per-grid value = c_ID:gname:dname, c_ID:gname:dname[I], f_ID:gname:dname, f_ID:gname:dname[I]</p>
|
|
<div class="highlight-none notranslate"><div class="highlight"><pre><span></span>gname = name of grid defined by compute or fix
|
|
dname = name of data field defined by compute or fix
|
|
c_ID = per-grid vector calculated by a compute with ID
|
|
c_ID[I] = Ith column of per-grid array calculated by a compute with ID, I can include wildcard (see below)
|
|
f_ID = per-grid vector calculated by a fix with ID
|
|
f_ID[I] = Ith column of per-grid array calculated by a fix with ID, I can include wildcard (see below)
|
|
</pre></div>
|
|
</div>
|
|
</li>
|
|
<li><p>zero or more keyword/arg pairs may be appended</p></li>
|
|
<li><p>keyword = <em>discard</em> or <em>norm</em> or <em>ave</em> or <em>bias</em> or <em>adof</em> or <em>cdof</em></p>
|
|
<pre class="literal-block"><em>discard</em> arg = <em>yes</em> or <em>no</em>
|
|
yes = discard an atom outside grid in a non-periodic dimension
|
|
no = remap an atom outside grid in a non-periodic dimension to first or last grid cell
|
|
<em>norm</em> arg = <em>all</em> or <em>sample</em> or <em>none</em> = how output on <em>Nfreq</em> steps is normalized
|
|
all = output is sum of atoms across all <em>Nrepeat</em> samples, divided by atom count
|
|
sample = output is sum of <em>Nrepeat</em> sample averages, divided by <em>Nrepeat</em>
|
|
none = output is sum of <em>Nrepeat</em> sample sums, divided by <em>Nrepeat</em>
|
|
<em>ave</em> args = <em>one</em> or <em>running</em> or <em>window M</em>
|
|
one = output new average value every Nfreq steps
|
|
running = output cumulative average of all previous Nfreq steps
|
|
window M = output average of M most recent Nfreq steps
|
|
<em>bias</em> arg = bias-ID
|
|
bias-ID = ID of a temperature compute that removes a velocity bias for temperature calculation
|
|
<em>adof</em> value = dof_per_atom
|
|
dof_per_atom = define this many degrees-of-freedom per atom for temperature calculation
|
|
<em>cdof</em> value = dof_per_grid_cell
|
|
dof_per_grid_cell = add this many degrees-of-freedom per grid_cell for temperature calculation</pre>
|
|
</li>
|
|
</ul>
|
|
</section>
|
|
<section id="examples">
|
|
<h2>Examples<a class="headerlink" href="#examples" title="Link to this heading"></a></h2>
|
|
<div class="highlight-LAMMPS notranslate"><div class="highlight"><pre><span></span><span class="k">fix </span><span class="nv nv-Identifier">1</span><span class="w"> </span><span class="nv nv-Identifier">all</span><span class="w"> </span><span class="n">ave</span><span class="o">/</span><span class="n">grid</span><span class="w"> </span><span class="m">10000</span><span class="w"> </span><span class="m">1</span><span class="w"> </span><span class="m">10000</span><span class="w"> </span><span class="m">10</span><span class="w"> </span><span class="m">10</span><span class="w"> </span><span class="m">10</span><span class="w"> </span><span class="n">fx</span><span class="w"> </span><span class="n">fy</span><span class="w"> </span><span class="n">fz</span><span class="w"> </span><span class="n">c_myMSD[</span><span class="o">*</span><span class="n">]</span>
|
|
<span class="k">fix </span><span class="nv nv-Identifier">1</span><span class="w"> </span><span class="nv nv-Identifier">flow</span><span class="w"> </span><span class="n">ave</span><span class="o">/</span><span class="n">grid</span><span class="w"> </span><span class="m">100</span><span class="w"> </span><span class="m">10</span><span class="w"> </span><span class="m">1000</span><span class="w"> </span><span class="m">20</span><span class="w"> </span><span class="m">20</span><span class="w"> </span><span class="m">30</span><span class="w"> </span><span class="n">f_TTM</span>:grid:data
|
|
</pre></div>
|
|
</div>
|
|
</section>
|
|
<section id="description">
|
|
<h2>Description<a class="headerlink" href="#description" title="Link to this heading"></a></h2>
|
|
<p>Overlay the 2d or 3d simulation box with a uniformly spaced 2d or 3d
|
|
grid and use it to either (a) time-average per-atom quantities for the
|
|
atoms in each grid cell, or to (b) time-average per-grid quantities
|
|
produced by other computes or fixes. This fix operates in either
|
|
“per-atom mode” (all input values are per-atom) or in “per-grid mode”
|
|
(all input values are per-grid). You cannot use both per-atom and
|
|
per-grid inputs in the same command.</p>
|
|
<p>The grid created by this command is distributed; each processor owns
|
|
the grid points that are within its subdomain. This is similar to
|
|
the <a class="reference internal" href="fix_ave_chunk.html"><span class="doc">fix ave/chunk</span></a> command when it uses chunks
|
|
from the <a class="reference internal" href="compute_chunk_atom.html"><span class="doc">compute chunk/atom</span></a> command which
|
|
are 2d or 3d regular bins. However, the per-bin outputs in that case
|
|
are global; each processor stores a copy of the entire set of bin
|
|
data. Thus it more efficient to use the fix ave/grid command when the
|
|
grid is large and a simulation is run on many processors.</p>
|
|
<p>For per-atom mode, only atoms in the specified group contribute to the
|
|
summing and averaging calculations. For per-grid mode, the specified
|
|
group is ignored.</p>
|
|
<hr class="docutils" />
|
|
<p>The <span class="math notranslate nohighlight">\(N_\text{every}\)</span>, <span class="math notranslate nohighlight">\(N_\text{repeat}\)</span>, and <span class="math notranslate nohighlight">\(N_\text{freq}\)</span>
|
|
arguments specify on what time steps the input values will be accessed and
|
|
contribute to the average. The final averaged quantities are generated on time
|
|
steps that are a multiples of <span class="math notranslate nohighlight">\(N_\text{freq}\)</span>. The average is over
|
|
<span class="math notranslate nohighlight">\(N_\text{repeat}\)</span> quantities, computed in the preceding portion of the
|
|
simulation every <span class="math notranslate nohighlight">\(N_\text{every}\)</span> time steps. <span class="math notranslate nohighlight">\(N_\text{freq}\)</span>
|
|
must be a multiple of <span class="math notranslate nohighlight">\(N_\text{every}\)</span> and <span class="math notranslate nohighlight">\(N_\text{every}\)</span> must be
|
|
non-zero even if <span class="math notranslate nohighlight">\(N_\text{repeat} = 1\)</span>. Also, the time steps
|
|
contributing to the average value cannot overlap (i.e.,
|
|
<span class="math notranslate nohighlight">\(N_\text{repeat} \times N_\text{every}\)</span> cannot exceed <span class="math notranslate nohighlight">\(N_\text{freq}\)</span>).</p>
|
|
<p>For example, if <span class="math notranslate nohighlight">\(N_\text{every}=2\)</span>, <span class="math notranslate nohighlight">\(N_\text{repeat}=6\)</span>, and
|
|
<span class="math notranslate nohighlight">\(N_\text{freq}=100\)</span>, then values on
|
|
time steps 90,92,94,96,98,100 will be used to compute the final average
|
|
on timestep 100. Similarly for timesteps 190,192,194,196,198,200 on
|
|
timestep 200, etc. If <span class="math notranslate nohighlight">\(N_\text{repeat}=1\)</span> and <span class="math notranslate nohighlight">\(N_\text{freq} = 100\)</span>, then no time
|
|
averaging is done; values are simply generated on timesteps
|
|
100,200,etc.</p>
|
|
<p>In per-atom mode, each input value can also be averaged over the atoms
|
|
in each grid cell. The way the averaging is done across the <span class="math notranslate nohighlight">\(N_\text{repeat}\)</span>
|
|
timesteps to produce output on the <span class="math notranslate nohighlight">\(N_\text{freq}\)</span> timesteps, and across
|
|
multiple <span class="math notranslate nohighlight">\(N_\text{freq}\)</span> outputs, is determined by the <em>norm</em> and <em>ave</em>
|
|
keyword settings, as discussed below.</p>
|
|
<hr class="docutils" />
|
|
<p>The <em>Nx</em>, <em>Ny</em>, and <em>Nz</em> arguments specify the size of the grid that
|
|
overlays the simulation box. For 2d simulations, <em>Nz</em> must be 1. The
|
|
<em>Nx</em>, <em>Ny</em>, <em>Nz</em> values can be any positive integer. The grid can be
|
|
very coarse compared to the particle count, or very fine. If one or
|
|
more of the values = 1, then bins are 2d planes or 1d slices of the
|
|
simulation domain. Note that if the total number of grid cells is
|
|
small, it may be more efficient to use the <a class="reference internal" href="fix_ave_chunk.html"><span class="doc">fix ave/chunk</span></a> command which can treat a grid defined by the
|
|
<a class="reference internal" href="compute_chunk_atom.html"><span class="doc">compute chunk/atom</span></a> command as a global
|
|
grid where each processor owns a copy of all the grid cells. If <em>Nx</em>
|
|
= <em>Ny</em> = <em>Nz</em> = 1 is used, the same calculation would be more
|
|
efficiently performed by the <a class="reference internal" href="fix_ave_atom.html"><span class="doc">fix ave/atom</span></a>
|
|
command.</p>
|
|
<p>If the simulation box size or shape changes during a simulation, the
|
|
grid always conforms to the size/shape of the current simulation box.
|
|
If one more dimensions have non-periodic shrink-wrapped boundary
|
|
conditions, as defined by the <a class="reference internal" href="boundary.html"><span class="doc">boundary</span></a> command, then
|
|
the grid will extend over the (dynamic) shrink-wrapped extent in each
|
|
dimension. If the box shape is triclinic, as explained in <a class="reference internal" href="Howto_triclinic.html"><span class="doc">Howto
|
|
triclinic</span></a>, then the grid is also triclinic; each
|
|
grid cell is a small triclinic cell with the same shape as the
|
|
simulation box.</p>
|
|
<hr class="docutils" />
|
|
<p>In both per-atom and per-grid mode, input values from a compute or fix
|
|
that produces an array of values (multiple values per atom or per grid
|
|
point), the bracketed index I can be specified using a wildcard
|
|
asterisk with the index to effectively specify multiple values. This
|
|
takes the form “*” or “*n” or “n*” or “m*n”. If N = the number of
|
|
columns in the array (for <em>mode</em> = vector), then an asterisk with no
|
|
numeric values means all indices from 1 to N. A leading asterisk
|
|
means all indices from 1 to n (inclusive). A trailing asterisk means
|
|
all indices from n to N (inclusive). A middle asterisk means all
|
|
indices from m to n (inclusive).</p>
|
|
<p>Using a wildcard is the same as if the individual columns of the array
|
|
had been listed one by one. E.g. if there were a compute fft/grid
|
|
command which produced 3 values for each grid point, these two fix
|
|
ave/grid commands would be equivalent:</p>
|
|
<div class="highlight-LAMMPS notranslate"><div class="highlight"><pre><span></span><span class="k">compute </span><span class="nv nv-Identifier">myFFT</span><span class="w"> </span><span class="nv nv-Identifier">all</span><span class="w"> </span><span class="n">fft</span><span class="o">/</span><span class="n">grid</span><span class="w"> </span><span class="m">10</span><span class="w"> </span><span class="m">10</span><span class="w"> </span><span class="m">10</span><span class="w"> </span><span class="n">...</span>
|
|
<span class="k">fix </span><span class="nv nv-Identifier">1</span><span class="w"> </span><span class="nv nv-Identifier">all</span><span class="w"> </span><span class="n">ave</span><span class="o">/</span><span class="n">grid</span><span class="w"> </span><span class="m">100</span><span class="w"> </span><span class="m">1</span><span class="w"> </span><span class="m">100</span><span class="w"> </span><span class="m">10</span><span class="w"> </span><span class="m">10</span><span class="w"> </span><span class="m">10</span><span class="w"> </span><span class="n">c_myFFT</span>:grid:data<span class="n">[</span><span class="o">*</span><span class="n">]</span>
|
|
<span class="k">fix </span><span class="nv nv-Identifier">2</span><span class="w"> </span><span class="nv nv-Identifier">all</span><span class="w"> </span><span class="n">ave</span><span class="o">/</span><span class="n">grid</span><span class="w"> </span><span class="m">100</span><span class="w"> </span><span class="m">1</span><span class="w"> </span><span class="m">100</span><span class="w"> </span><span class="m">10</span><span class="w"> </span><span class="m">10</span><span class="w"> </span><span class="m">10</span><span class="w"> </span><span class="n">c_myFFT</span>:grid:data<span class="n">[</span><span class="o">*</span><span class="n">][1]</span><span class="w"> </span><span class="n">c_myFFT</span>:grid:data<span class="n">[</span><span class="o">*</span><span class="n">][2]</span><span class="w"> </span><span class="n">c_myFFT</span>:grid:data<span class="n">[3]</span>
|
|
</pre></div>
|
|
</div>
|
|
<hr class="docutils" />
|
|
<p><em>Per-atom mode</em>:</p>
|
|
<p>Each specified per-atom value can be an atom attribute (velocity,
|
|
force component), a number or mass density, a mass or temperature, or
|
|
the result of a <a class="reference internal" href="compute.html"><span class="doc">compute</span></a> or <a class="reference internal" href="fix.html"><span class="doc">fix</span></a> or the
|
|
evaluation of an atom-style <a class="reference internal" href="variable.html"><span class="doc">variable</span></a>. In the latter
|
|
cases, the compute, fix, or variable must produce a per-atom quantity,
|
|
not a global quantity. Note that the <a class="reference internal" href="compute_property_atom.html"><span class="doc">compute property/atom</span></a> command provides access to any attribute
|
|
defined and stored by atoms.</p>
|
|
<p>The per-atom values of each input vector are summed and averaged
|
|
independently of the per-atom values in other input vectors.</p>
|
|
<p><a class="reference internal" href="compute.html"><span class="doc">Computes</span></a> that produce per-atom quantities are those
|
|
which have the word <em>atom</em> in their style name. See the doc pages for
|
|
individual <a class="reference internal" href="fix.html"><span class="doc">fixes</span></a> to determine which ones produce per-atom
|
|
quantities. <a class="reference internal" href="variable.html"><span class="doc">Variables</span></a> of style <em>atom</em> are the only
|
|
ones that can be used with this fix since all other styles of variable
|
|
produce global quantities.</p>
|
|
<hr class="docutils" />
|
|
<p>The atom attribute values (vx,vy,vz,fx,fy,fz,mass) are
|
|
self-explanatory. As noted above, any other atom attributes can be
|
|
used as input values to this fix by using the <a class="reference internal" href="compute_property_atom.html"><span class="doc">compute
|
|
property/atom</span></a> command and then specifying an
|
|
input value from that compute.</p>
|
|
<p>The <em>density/number</em> value means the number density is computed for
|
|
each grid cell, i.e. number/volume. The <em>density/mass</em> value means
|
|
the mass density is computed for each grid/cell,
|
|
i.e. total-mass/volume. The output values are in units of 1/volume or
|
|
density (mass/volume). See the <a class="reference internal" href="units.html"><span class="doc">units</span></a> command page for
|
|
the definition of density for each choice of units, e.g. gram/cm^3.</p>
|
|
<p>The <em>temp</em> value computes the temperature for each grid cell, by the
|
|
formula</p>
|
|
<div class="math notranslate nohighlight">
|
|
\[\text{KE} = \frac{\text{DOF}}{2} k_B T,\]</div>
|
|
<p>where KE = total kinetic energy of the atoms in the grid cell (
|
|
<span class="math notranslate nohighlight">\(\frac{1}{2} m v^2\)</span>), DOF = the total number of degrees of
|
|
freedom for all atoms in the grid cell, <span class="math notranslate nohighlight">\(k_B\)</span> = Boltzmann
|
|
constant, and <span class="math notranslate nohighlight">\(T\)</span> = temperature.</p>
|
|
<p>The DOF is calculated as N*adof + cdof, where N = number of atoms in
|
|
the grid cell, adof = degrees of freedom per atom, and cdof = degrees
|
|
of freedom per grid cell. By default adof = 2 or 3 = dimensionality
|
|
of system, as set via the <a class="reference internal" href="dimension.html"><span class="doc">dimension</span></a> command, and
|
|
cdof = 0.0. This gives the usual formula for temperature.</p>
|
|
<p>Note that currently this temperature only includes translational
|
|
degrees of freedom for each atom. No rotational degrees of freedom
|
|
are included for finite-size particles. Also no degrees of freedom
|
|
are subtracted for any velocity bias or constraints that are applied,
|
|
such as <a class="reference internal" href="compute_temp_partial.html"><span class="doc">compute temp/partial</span></a>, or
|
|
<a class="reference internal" href="fix_shake.html"><span class="doc">fix shake</span></a> or <a class="reference internal" href="fix_rigid.html"><span class="doc">fix rigid</span></a>. This is
|
|
because those degrees of freedom (e.g. a constrained bond) could apply
|
|
to sets of atoms that are both inside and outside a specific grid
|
|
cell, and hence the concept is somewhat ill-defined. In some cases,
|
|
you can use the <em>adof</em> and <em>cdof</em> keywords to adjust the calculated
|
|
degrees of freedom appropriately, as explained below.</p>
|
|
<p>Also note that a bias can be subtracted from atom velocities before
|
|
they are used in the above formula for KE, by using the <em>bias</em>
|
|
keyword. This allows, for example, a thermal temperature to be
|
|
computed after removal of a flow velocity profile.</p>
|
|
<p>Note that the per-grid-cell temperature calculated by this fix and the
|
|
<a class="reference internal" href="compute_temp_chunk.html"><span class="doc">compute temp/chunk</span></a> command (using bins)
|
|
can be different. The compute calculates the temperature for each
|
|
chunk for a single snapshot. This fix can do that but can also time
|
|
average those values over many snapshots, or it can compute a
|
|
temperature as if the atoms in the grid cell on different timesteps
|
|
were collected together as one set of atoms to calculate their
|
|
temperature. The compute allows the center-of-mass velocity of each
|
|
chunk to be subtracted before calculating the temperature; this fix
|
|
does not.</p>
|
|
<p>If a value begins with “c_”, a compute ID must follow which has been
|
|
previously defined in the input script. If no bracketed integer is
|
|
appended, the per-atom vector calculated by the compute is used. If a
|
|
bracketed integer is appended, the Ith column of the per-atom array
|
|
calculated by the compute is used. Users can also write code for
|
|
their own compute styles and <a class="reference internal" href="Modify.html"><span class="doc">add them to LAMMPS</span></a>. See
|
|
the discussion above for how I can be specified with a wildcard
|
|
asterisk to effectively specify multiple values.</p>
|
|
<p>If a value begins with “f_”, a fix ID must follow which has been
|
|
previously defined in the input script. If no bracketed integer is
|
|
appended, the per-atom vector calculated by the fix is used. If a
|
|
bracketed integer is appended, the Ith column of the per-atom array
|
|
calculated by the fix is used. Note that some fixes only produce
|
|
their values on certain timesteps, which must be compatible with
|
|
<span class="math notranslate nohighlight">\(N_\text{every}\)</span>, else an error results. Users can also write code for their
|
|
own fix styles and <a class="reference internal" href="Modify.html"><span class="doc">add them to LAMMPS</span></a>. See the
|
|
discussion above for how I can be specified with a wildcard asterisk
|
|
to effectively specify multiple values.</p>
|
|
<p>If a value begins with “v_”, a variable name must follow which has
|
|
been previously defined in the input script. Variables of style
|
|
<em>atom</em> can reference thermodynamic keywords and various per-atom
|
|
attributes, or invoke other computes, fixes, or variables when they
|
|
are evaluated, so this is a very general means of generating per-atom
|
|
quantities to average within grid cells.</p>
|
|
<hr class="docutils" />
|
|
<p><em>Per-grid mode</em>:</p>
|
|
<p>The attributes that begin with <em>c_ID</em> and <em>f_ID</em> both take
|
|
colon-separated fields <em>gname</em> and <em>dname</em>. These refer to a grid
|
|
name and data field name which is defined by the compute or fix. Note
|
|
that a compute or fix can define one or more grids (of different
|
|
sizes) and one or more data fields for each of those grids. The sizes
|
|
of all grids used as values for one instance of this fix must be the
|
|
same.</p>
|
|
<p>The <em>c_ID:gname:dname</em> and <em>c_ID:gname:dname[I]</em> attributes allow
|
|
per-grid vectors or arrays calculated by a <a class="reference internal" href="compute.html"><span class="doc">compute</span></a> to
|
|
be accessed. The ID in the attribute should be replaced by the actual
|
|
ID of the compute that has been defined previously in the input
|
|
script.</p>
|
|
<p>If <em>c_ID:gname:dname</em> is used as a attribute, then the per-grid vector
|
|
calculated by the compute is accessed. If <em>c_ID:gname:dname[I]</em> is
|
|
used, then I must be in the range from 1-M, which will access the Ith
|
|
column of the per-grid array with M columns calculated by the compute.
|
|
See the discussion above for how I can be specified with a wildcard
|
|
asterisk to effectively specify multiple values.</p>
|
|
<p>The <em>f_ID:gname:dname</em> and <em>f_ID:gname:dname[I]</em> attributes allow
|
|
per-grid vectors or arrays calculated by a <a class="reference internal" href="fix.html"><span class="doc">fix</span></a> to be
|
|
output. The ID in the attribute should be replaced by the actual ID
|
|
of the fix that has been defined previously in the input script.</p>
|
|
<p>If <em>f_ID:gname:dname</em> is used as a attribute, then the per-grid vector
|
|
calculated by the fix is printed. If <em>f_ID:gname:dname[I]</em> is used,
|
|
then I must be in the range from 1-M, which will print the Ith column
|
|
of the per-grid with M columns calculated by the fix. See the
|
|
discussion above for how I can be specified with a wildcard asterisk
|
|
to effectively specify multiple values.</p>
|
|
<hr class="docutils" />
|
|
<p>Additional optional keywords also affect the operation of this fix and
|
|
its outputs. Some are only applicable to per-atom mode. Some are
|
|
applicable to both per-atom and per-grid mode.</p>
|
|
<p>The <em>discard</em> keyword is only applicable to per-atom mode. If a
|
|
dimension of the system is non-periodic, then grid cells will only
|
|
span the box dimension (fixed or shrink-wrap boundaries as set by the
|
|
<a class="reference internal" href="boundary.html"><span class="doc">boundary command</span></a> command). An atom may thus be slightly outside the
|
|
range of grid cells on a particular timestep. If <em>discard</em> is set to
|
|
<em>yes</em> (the default), then the atom will be assigned to the closest
|
|
grid cell (lowest or highest) in that dimension. If <em>discard</em> is set
|
|
to <em>no</em> the atom will be ignored.</p>
|
|
<hr class="docutils" />
|
|
<p>The <em>norm</em> keyword is only applicable to per-atom mode. In per-grid
|
|
mode, the <em>norm</em> keyword setting is ignored. The output grid value on
|
|
an <span class="math notranslate nohighlight">\(N_\text{freq}\)</span> timestep is the sum of the grid values in each of the
|
|
<span class="math notranslate nohighlight">\(N_\text{repeat}\)</span> samples, divided by <span class="math notranslate nohighlight">\(N_\text{repeat}\)</span>.</p>
|
|
<p>In per-atom mode, the <em>norm</em> keyword affects how averaging is done for
|
|
the per-grid values that are output on an <span class="math notranslate nohighlight">\(N_\text{freq}\)</span> timestep. <span class="math notranslate nohighlight">\(N_\text{repeat}\)</span>
|
|
samples contribute to the output. The <em>norm</em> keyword has 3 possible
|
|
settings: <em>all</em> or <em>sample</em> or <em>none</em>. <em>All</em> is the default.</p>
|
|
<p>In the formulas that follow, SumI is the sum of a per-atom property
|
|
over the CountI atoms in a grid cell for a single sample I, where I
|
|
varies from 1 to N, and N = Nrepeat. These formulas are used for any
|
|
per-atom input value listed above, except <em>density/number</em>,
|
|
<em>density/mass</em>, and <em>temp</em>. Those input values are discussed below.</p>
|
|
<p>In per-atom mode, for <em>norm all</em> the output grid value on the <span class="math notranslate nohighlight">\(N_\text{freq}\)</span>
|
|
timestep is an average over atoms across the entire <span class="math notranslate nohighlight">\(N_\text{freq}\)</span> timescale:</p>
|
|
<p>Output = (Sum1 + Sum2 + … + SumN) / (Count1 + Count2 + … + CountN)</p>
|
|
<p>In per-atom mode, for <em>norm sample</em> the output grid value on the
|
|
<span class="math notranslate nohighlight">\(N_\text{freq}\)</span> timestep is an average of an average:</p>
|
|
<p>Output = (Sum1/Count1 + Sum2/Count2 + … + SumN/CountN) / Nrepeat</p>
|
|
<p>In per-atom mode, for <em>norm none</em> the output grid value on the
|
|
<span class="math notranslate nohighlight">\(N_\text{freq}\)</span> timestep is not normalized by the atom counts:</p>
|
|
<p>Output = (Sum1 + Sum2 + … SumN) / Nrepeat</p>
|
|
<p>For <em>density/number</em> and <em>density/mass</em>, the output value is the same
|
|
as in the formulas above for <em>norm all</em> and <em>norm sample</em>, except that
|
|
the result is also divided by the grid cell volume. For <em>norm all</em>,
|
|
this will be the volume at the final <span class="math notranslate nohighlight">\(N_\text{freq}\)</span> timestep. For <em>norm
|
|
sample</em>, the divide-by-volume is done for each sample, using the grid
|
|
cell volume at the sample timestep. For <em>norm none</em>, the output is
|
|
the same as for <em>norm all</em>.</p>
|
|
<p>For <em>temp</em>, the output temperature uses the formula for kinetic energy
|
|
KE listed above, and is normalized similarly to the formulas above for
|
|
<em>norm all</em> and <em>norm sample</em>, except for the way the degrees of
|
|
freedom (DOF) are calculated. For <em>norm none</em>, the output is the same
|
|
as for <em>norm all</em>.</p>
|
|
<p>For <em>norm all</em>, the DOF = <span class="math notranslate nohighlight">\(N_\text{repeat} \times\)</span> <em>cdof</em> plus <em>Count</em> times
|
|
<em>adof</em>, where <em>Count</em> = (Count1 + Count2 + … + CountN). The <em>cdof</em>
|
|
and <em>adof</em> keywords are discussed below. The output temperature is
|
|
computed with all atoms across all samples contributing.</p>
|
|
<p>For <em>norm sample</em>, the DOF for a single sample = <em>cdof</em> plus <em>Count</em>
|
|
times <em>adof</em>, where <em>Count</em> = CountI for a single sample. The output
|
|
temperature is the average of <em>Nsample</em> temperatures calculated for
|
|
each sample.</p>
|
|
<p>Finally, for all 3 <em>norm</em> settings the output count of atoms per grid
|
|
cell is:</p>
|
|
<p>Output count = (Count1 + Count2 + … CountN) / Nrepeat</p>
|
|
<p>This count is the same for all per-atom input values, including
|
|
<em>density/number</em>, <em>density/mass</em>, and <em>temp</em>.</p>
|
|
<hr class="docutils" />
|
|
<p>The <em>ave</em> keyword is applied to both per-atom and per-grid mode. It
|
|
determines how the per-grid values produced once every <span class="math notranslate nohighlight">\(N_\text{freq}\)</span> steps
|
|
are averaged with values produced on previous steps that were
|
|
multiples of <span class="math notranslate nohighlight">\(N_\text{freq}\)</span>, before they are accessed by another output
|
|
command.</p>
|
|
<p>If the <em>ave</em> setting is <em>one</em>, which is the default, then the grid
|
|
values produced on <span class="math notranslate nohighlight">\(N_\text{freq}\)</span> timesteps are independent of each other;
|
|
they are output as-is without further averaging.</p>
|
|
<p>If the <em>ave</em> setting is <em>running</em>, then the grid values produced on
|
|
<span class="math notranslate nohighlight">\(N_\text{freq}\)</span> timesteps are summed and averaged in a cumulative sense before
|
|
being output. Each output grid value is thus the average of the grid
|
|
value produced on that timestep with all preceding values for the same
|
|
grid value. This running average begins when the fix is defined; it
|
|
can only be restarted by deleting the fix via the <a class="reference internal" href="unfix.html"><span class="doc">unfix</span></a>
|
|
command, or re-defining the fix by re-specifying it.</p>
|
|
<p>If the <em>ave</em> setting is <em>window</em>, then the grid values produced on
|
|
<span class="math notranslate nohighlight">\(N_\text{freq}\)</span> timesteps are summed and averaged within a moving “window” of
|
|
time, so that the last M values for the same grid are used to produce
|
|
the output. E.g. if M = 3 and Nfreq = 1000, then the grid value
|
|
output on step 10000 will be the average of the grid values on steps
|
|
8000,9000,10000. Outputs on early steps will average over less than M
|
|
values if they are not available.</p>
|
|
<hr class="docutils" />
|
|
<p>The <em>bias</em>, <em>adof</em>, and <em>cdof</em> keywords are only applicable to
|
|
per-atom mode.</p>
|
|
<p>The <em>bias</em> keyword specifies the ID of a temperature compute that
|
|
removes a “bias” velocity from each atom, specified as <em>bias-ID</em>.
|
|
It is only used when the <em>temp</em> value is calculated, to compute the
|
|
thermal temperature of each grid cell after the translational kinetic
|
|
energy components have been altered in a prescribed way, e.g. to
|
|
remove a flow velocity profile. See the doc pages for individual
|
|
computes that calculate a temperature to see which ones implement a
|
|
bias.</p>
|
|
<p>The <em>adof</em> and <em>cdof</em> keywords define the values used in the degree of
|
|
freedom (DOF) formula described above for temperature calculation for
|
|
each grid cell. They are only used when the <em>temp</em> value is
|
|
calculated. They can be used to calculate a more appropriate
|
|
temperature in some cases. Here are 3 examples:</p>
|
|
<p>If grid cells contain some number of water molecules and <a class="reference internal" href="fix_shake.html"><span class="doc">fix
|
|
shake</span></a> is used to make each molecule rigid, then you could
|
|
calculate a temperature with 6 degrees of freedom (DOF) (3
|
|
translational, 3 rotational) per molecule by setting <em>adof</em> to 2.0.</p>
|
|
<p>If <a class="reference internal" href="compute_temp_partial.html"><span class="doc">compute temp/partial</span></a> is used with the
|
|
<em>bias</em> keyword to only allow the x component of velocity to contribute
|
|
to the temperature, then <em>adof</em> = 1.0 would be appropriate.</p>
|
|
<p>Using <em>cdof</em> = -2 or -3 (for 2d or 3d simulations) will subtract out 2
|
|
or 3 degrees of freedom for each grid cell, similar to how the
|
|
<a class="reference internal" href="compute_temp.html"><span class="doc">compute temp</span></a> command subtracts out 3 DOF for the
|
|
entire system.</p>
|
|
</section>
|
|
<hr class="docutils" />
|
|
<section id="restart-fix-modify-output-run-start-stop-minimize-info">
|
|
<h2>Restart, fix_modify, output, run start/stop, minimize info<a class="headerlink" href="#restart-fix-modify-output-run-start-stop-minimize-info" title="Link to this heading"></a></h2>
|
|
<p>No information about this fix is written to <a class="reference internal" href="restart.html"><span class="doc">binary restart files</span></a>. None of the <a class="reference internal" href="fix_modify.html"><span class="doc">fix_modify</span></a> options are
|
|
relevant to this fix.</p>
|
|
<p>This fix calculates a per-grid array which has one column for each of
|
|
the specified input values. The units for each column with be in the
|
|
<a class="reference internal" href="units.html"><span class="doc">units</span></a> for the per-atom or per-grid quantity for the
|
|
corresponding input value. If the fix is used in per-atom mode, it
|
|
also calculates a per-grid vector with the count of atoms in each grid
|
|
cell. The number of rows in the per-grid array and number of values
|
|
in the per-grid vector (distributed across all processors) is Nx *
|
|
Ny * Nz.</p>
|
|
<p>For access by other commands, the name of the single grid produced by
|
|
this fix is “grid”. The names of its two per-grid datums are “data”
|
|
for the per-grid array and “count” for the per-grid vector (if using
|
|
per-atom values). Both datums can be accessed by various <a class="reference internal" href="Howto_output.html"><span class="doc">output
|
|
commands</span></a>.</p>
|
|
<p>In per-atom mode, the per-grid array values calculated by this fix are
|
|
treated as “intensive”, since they are typically already normalized by
|
|
the count of atoms in each grid cell.</p>
|
|
<p>No parameter of this fix can be used with the <em>start/stop</em> keywords of
|
|
the <a class="reference internal" href="run.html"><span class="doc">run</span></a> command. This fix is not invoked during
|
|
<a class="reference internal" href="minimize.html"><span class="doc">energy minimization</span></a>.</p>
|
|
</section>
|
|
<section id="restrictions">
|
|
<h2>Restrictions<a class="headerlink" href="#restrictions" title="Link to this heading"></a></h2>
|
|
<p>none</p>
|
|
</section>
|
|
<section id="related-commands">
|
|
<h2>Related commands<a class="headerlink" href="#related-commands" title="Link to this heading"></a></h2>
|
|
<p><a class="reference internal" href="fix_ave_atom.html"><span class="doc">fix ave/atom</span></a>, <a class="reference internal" href="fix_ave_chunk.html"><span class="doc">fix ave/chunk</span></a></p>
|
|
</section>
|
|
<section id="default">
|
|
<h2>Default<a class="headerlink" href="#default" title="Link to this heading"></a></h2>
|
|
<p>The option defaults are discard = yes, norm = all, ave = one, and bias
|
|
= none.</p>
|
|
</section>
|
|
</section>
|
|
|
|
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