Fix langevin documentation

LAMMPS
1

The manual has the following note for fix langevin:

This accumulated energy does NOT include kinetic energy removed by the zero flag. LAMMPS will print a warning when both options are active.

However, if I issue the command:

fix 1 all langevin 300. 300. $(100*dt) 185497 angmom 1.0 zero yes tally yes

No warning is issued. Has the option zero yes changed to conserve the kinetic energy?

Here is a minimal script to play with the fix.

test_langevin.in 
# GayBerne ellipsoids in LJ background fluid

units        lj
atom_style   ellipsoid
dimension    2

lattice      sq 0.01
region       box block 0 20 0 20 -0.5 0.5
create_box   1 box
create_atoms 1 box

set          type 1 mass 1.0
set          type 1 shape 3 2 1
set          group all quat/random 18238
compute      rot all temp/asphere
velocity     all create 2.4 87287 loop geom

pair_style   gayberne 1.0 3.0 1.0 4.0
pair_coeff   1 1 1.5 3.0 0.4 0.8 1 0.4 0.8 1 2.5
neighbor     0.8 bin

thermo_style custom step c_rot epair etotal press vol
thermo       100


compute      0 all property/atom quatw quati quatj quatk shapex shapey shapez

dump        1 all custom 100 test_langevin.dump id type x y z c_0[*]
dump_modify 1 colname c_0[1] quatw colname c_0[2] quati colname c_0[3] quatj colname c_0[4] quatk &
              colname c_0[5] shapex colname c_0[6] shapey colname c_0[7] shapez
timestep     0.001
fix          1 all npt/asphere temp 2.0 2.0 0.1 iso 0.0 1.0 1.0 &
               mtk no pchain 0 tchain 1
fix          2 all enforce2d

# equilibrate to shrink box around dilute system
run          2000

# Check the option 
unfix        1
fix          1 all nve/asphere
fix 3 all langevin 2.0 2.0 0.1 185497 angmom 1.0 zero yes tally yes
run          20000
2

From git log src/fix_langevin.cpp:

  commit 8020f5b9650f078c8aad2ec0c83cf67a02bd0901
  Author: Donatas Surblys <[email protected]>
  Date:   Thu Feb 14 18:54:59 2019 +0900
  
*     remove warning messages when using 'tally yes zero yes' with fix langevin
  
  commit b3a7a534a99b85c97b863f46c13684bf1422fbf2
  Author: Donatas Surblys <[email protected]>
  Date:   Thu Feb 14 18:54:59 2019 +0900
  
      make fix langevin correctly account for energy with 'zero yes'

So, the answer is “yes” and the note from the documentation needs to be removed.

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