Previous Section - LAMMPS WWW Site - LAMMPS Documentation - LAMMPS Commands - Next Section

9. Errors

This section describes the various kinds of errors you can encounter when using LAMMPS.

9.1 Common problems
9.2 Reporting bugs
9.3 Error & warning messages

9.1 Common problems

If two LAMMPS runs do not produce the same answer on different machines or different numbers of processors, this is typically not a bug. In theory you should get identical answers on any number of processors and on any machine. In practice, numerical round-off can cause slight differences and eventual divergence of molecular dynamics phase space trajectories within a few 100s or few 1000s of timesteps. However, the statistical properties of the two runs (e.g. average energy or temperature) should still be the same.

If the velocity command is used to set initial atom velocities, a particular atom can be assigned a different velocity when the problem on different machines. Obviously, this means the phase space trajectories of the two simulations will rapidly diverge. See the discussion of the loop option in the velocity command for details.

A LAMMPS simulation typically has two stages, setup and run. Most LAMMPS errors are detected at setup time; others like a bond stretching too far may not occur until the middle of a run.

LAMMPS tries to flag errors and print informative error messages so you can fix the problem. Of course LAMMPS cannot figure out your physics mistakes, like choosing too big a timestep, specifying invalid force field coefficients, or putting 2 atoms on top of each other! If you find errors that LAMMPS doesn't catch that you think it should flag, please send an email to the developers.

If you get an error message about an invalid command in your input script, you can determine what command is causing the problem by looking in the log.lammps file or using the echo command to see it on the screen. For a given command, LAMMPS expects certain arguments in a specified order. If you mess this up, LAMMPS will often flag the error, but it may read a bogus argument and assign a value that is valid, but not what you wanted. E.g. trying to read the string "abc" as an integer value and assigning the associated variable a value of 0.

Generally, LAMMPS will print a message to the screen and exit gracefully when it encounters a fatal error. Sometimes it will print a WARNING and continue on; you can decide if the WARNING is important or not. If LAMMPS crashes or hangs without spitting out an error message first then it could be a bug (see this section) or one of the following cases:

LAMMPS runs in the available memory a processor allows to be allocated. Most reasonable MD runs are compute limited, not memory limited, so this shouldn't be a bottleneck on most platforms. Almost all large memory allocations in the code are done via C-style malloc's which will generate an error message if you run out of memory. Smaller chunks of memory are allocated via C++ "new" statements. If you are unlucky you could run out of memory just when one of these small requests is made, in which case the code will crash or hang (in parallel), since LAMMPS doesn't trap on those errors.

Illegal arithmetic can cause LAMMPS to run slow or crash. This is typically due to invalid physics and numerics that your simulation is computing. If you see wild thermodynamic values or NaN values in your LAMMPS output, something is wrong with your simulation.

In parallel, one way LAMMPS can hang is due to how different MPI implementations handle buffering of messages. If the code hangs without an error message, it may be that you need to specify an MPI setting or two (usually via an environment variable) to enable buffering or boost the sizes of messages that can be buffered.


9.2 Reporting bugs

If you are confident that you have found a bug in LAMMPS, please send an email to the developers.

First, check the "New features and bug fixes" section of the LAMMPS WWW site to see if the bug has already been reported or fixed.

If not, the most useful thing you can do for us is to isolate the problem. Run it on the smallest number of atoms and fewest number of processors and with the simplest input script that reproduces the bug.

In your email, describe the problem and any ideas you have as to what is causing it or where in the code the problem might be. We'll request your input script and data files if necessary.


9.3 Error & warning Messages

These are two alphabetic lists of the ERROR and WARNING messages LAMMPS prints out and the reason why. If the explanation here is not sufficient, the documentation for the offending command may help. Grepping the source files for the text of the error message and staring at the source code and comments is also not a bad idea! Note that sometimes the same message can be printed from multiple places in the code.

Errors:

1-3 bond count is inconsistent
An inconsistency was detected when computing the number of 1-3 neighbors for each atom. This likely means something is wrong with the bond topologies you have defined.
1-4 bond count is inconsistent
An inconsistency was detected when computing the number of 1-4 neighbors for each atom. This likely means something is wrong with the bond topologies you have defined.
All angle coeffs are not set
All angle coefficients must be set in the data file or by the angle_coeff command before running a simulation.
All bond coeffs are not set
All bond coefficients must be set in the data file or by the bond_coeff command before running a simulation.
All EAM pair coeffs are not set
All EAM pair coefficients must be set in the data file or by the pair_coeff command before running a simulation.
All dihedral coeffs are not set
All dihedral coefficients must be set in the data file or by the dihedral_coeff command before running a simulation.
All dipole moments are not set
For atom styles that define dipole moments for each atom type, all moments must be set in the data file or by the dipole command before running a simulation.
All improper coeffs are not set
All improper coefficients must be set in the data file or by the improper_coeff command before running a simulation.
All masses are not set
For atom styles that define masses for each atom type, all masses must be set in the data file or by the mass command before running a simulation. They must also be set before using the velocity command.
All pair coeffs are not set
All pair coefficients must be set in the data file or by the pair_coeff command before running a simulation.
All universe variables must have same # of values
Self-explanatory.
All variables in next command must be same style
Self-explanatory.
Angle atoms %d %d %d missing on proc %d at step %d
One or more of 3 atoms needed to compute a particular angle are missing on this processor. Typically this is because the pairwise cutoff is set too short or the angle has blown apart and an atom is too far away.
Angle atom missing in delete_bonds
The delete_bonds command cannot find one or more atoms in a particular angle on a particular processor. The pairwise cutoff is too short or the atoms are too far apart to make a valid angle.
Angle atom missing in set command
The set command cannot find one or more atoms in a particular angle on a particular processor. The pairwise cutoff is too short or the atoms are too far apart to make a valid angle.
Angle coeffs are not set
No angle coefficients have been assigned in the data file or via the angle_coeff command.
Angle_coeff command before angle_style is defined
Coefficients cannot be set in the data file or via the angle_coeff command until an angle_style has been assigned.
Angle_coeff command before simulation box is defined
The angle_coeff command cannot be used before a read_data, read_restart, or create_box command.
Angle_coeff command when no angles allowed
The chosen atom style does not allow for angles to be defined.
Angle coeff for hybrid has invalid style
Angle style hybrid uses another angle style as one of its coefficients. The angle style used in the angle_coeff command or read from a restart file is not recognized.
Angles assigned incorrectly
Angles read in from the data file were not assigned correctly to atoms. This means there is something invalid about the topology definitions.
Angles defined but no angle types
The data file header lists angles but no angle types.
Angle style hybrid cannot have hybrid as an argument
Self-explanatory.
Angle style hybrid cannot use same angle style twice
Self-explanatory.
Another input script is already being processed
Cannot attempt to open a 2nd input script, when the original file is still being processed.
Atom count is inconsistent, cannot write restart file
Sum of atoms across processors does not equal initial total count. This is probably because you have lost some atoms.
Atom IDs must be consecutive for dump dcd
Self-explanatory.
Atom IDs must be consecutive for dump xtc
Self-explanatory.
Atom IDs must be consecutive for dump xyz
Self-explanatory.
Atom in too many rigid bodies - boost MAXBODY
Fix poems has a parameter MAXBODY (in fix_poems.cpp) which determines the maximum number of rigid bodies a single atom can belong to (i.e. a multibody joint). The bodies you have defined exceed this limit.
Atom_modify command after simulation box is defined
The atom_modify command cannot be used after a read_data, read_restart, or create_box command.
Atom_modify command before atom_style command
The atom_modify command cannot be used before an atom style has been defined.
Atom style granular and dpd cannot be used together
Self-explanatory.
Atom style hybrid cannot have hybrid as an argument
Self-explanatory. Check the input script.
Atom_style command after simulation box is defined
The atom_style command cannot be used after a read_data, read_restart, or create_box command.
Attempting to rescale a 0.0 temperature
Cannot rescale a temperature that is already 0.0.
Bad FENE bond
Two atoms in a FENE bond have become so far apart that the bond cannot be computed.
Bad grid of processors
The 3d grid of processors defined by the processors command does not match the number of processors LAMMPS is being run on.
Bad principal moments
Fix rigid did not compute the principal moments of inertia of a rigid group of atoms correctly.
Bad slab parameter
Kspace_modify value for the slab/volume keyword must be >= 2.0.
Bitmapped lookup tables require int/float be same size
Cannot use pair tables on this machine, because of word sizes. Use the pair_modify command with table 0 instead.
Bitmapped table is incorrect length in table file
Number of table entries is not a correct power of 2.
Bitmapped table in file does not match requested table
Setting for bitmapped table in pair_coeff command must match table in file exactly.
Bond and angle potentials must be defined for TIP4P
Cannot use TIP4P pair potential unless bond and angle potentials are defined.
Bond atom missing in delete_bonds
The delete_bonds command cannot find one or more atoms in a particular bond on a particular processor. The pairwise cutoff is too short or the atoms are too far apart to make a valid bond.
Bond atom missing in set command
The set command cannot find one or more atoms in a particular bond on a particular processor. The pairwise cutoff is too short or the atoms are too far apart to make a valid bond.
Bond atoms %d %d missing on proc %d at step %d
One or more of 2 atoms needed to compute a particular bond are missing on this processor. Typically this is because the pairwise cutoff is set too short or the bond has blown apart and an atom is too far away.
Bond coeff for hybrid has invalid style
Bond style hybrid uses another bond style as one of its coefficients. The bond style used in the bond_coeff command or read from a restart file is not recognized.
Bond_coeff command before bond_style is defined
Coefficients cannot be set in the data file or via the bond_coeff command until an bond_style has been assigned.
Bond_coeff command before simulation box is defined
The bond_coeff command cannot be used before a read_data, read_restart, or create_box command.
Bond_coeff command when no bonds allowed
The chosen atom style does not allow for bonds to be defined.
Bond coeffs are not set
No bond coefficients have been assigned in the data file or via the bond_coeff command.
Bond potential must be defined for SHAKE
Cannot use fix shake unless bond potential is defined.
Bonds assigned incorrectly
Bonds read in from the data file were not assigned correctly to atoms. This means there is something invalid about the topology definitions.
Bonds defined but no bond types
The data file header lists bonds but no bond types.
Bond style hybrid cannot have hybrid as an argument
Self-explanatory. Check the input script.
Bond style hybrid cannot use same bond style twice
The sub-style arguments of bond_style hybrid cannot be duplicated. Check the input script.
Bond style quartic cannot be used with 3,4-body interactions
No angle, dihedral, or improper styles can be defined when using bond style quartic.
Both sides of boundary must be periodic
Cannot specify a boundary as periodic only on the lo or hi side. Must be periodic on both sides.
Boundary command after simulation box is defined
The boundary command cannot be used after a read_data, read_restart, or create_box command.
Box bounds are invalid
The box boundaries specified in the read_data file are invalid. The lo value must be less than the hi value for all 3 dimensions.
Can only wiggle zcylinder wall in z dim
The Self-explanatory.
Cannot change dump_modify every for dump dcd
The frequency of writing dump dcd snapshots cannot be changed.
Cannot compute PPPM G
LAMMPS failed to compute a valid approximation for the PPPM g_ewald factor that partitions the computation between real space and k-space.
Cannot compute PPPM X grid spacing
LAMMPS failed to compute a valid PPPM grid spacing in the x dimension.
Cannot compute PPPM Y grid spacing
LAMMPS failed to compute a valid PPPM grid spacing in the y dimension.
Cannot compute PPPM Z grid spacing
LAMMPS failed to compute a valid PPPM grid spacing in the z dimension.
Cannot create atoms with undefined lattice
Must use the lattice command before using the create_atoms command.
Cannot create an atom map unless atoms have IDs
The simulation requires a mapping from global atom IDs to local atoms, but the atoms that have been defined have no IDs.
Cannot create_box after simulation box is defined
The create_box command cannot be used after a read_data, read_restart, or create_box command.
Cannot create_box until atom_style is defined
Self-explanatory.
Cannot evaluate variable equal command
Syntax or keyword names in mathematical expression are not recognized.
Cannot find delete_bonds group ID
Group ID used in the delete_bonds command does not exist.
Cannot find set command group ID
Group ID used in the set command does not exist.
Cannot fix nph on a non-periodic dimension
Pressure can only be controlled on a dimension that is periodic.
Cannot fix npt on a non-periodic dimension
Pressure can only be controlled on a dimension that is periodic.
Cannot fix volume/rescale on a non-periodic boundary
Volume can only be rescaled on a dimension that is periodic.
Cannot fix uniaxial on non-periodic system
Volume can only be rescaled uniaxially if system is periodic in all 3 dimensions.
Cannot have both pair_modify shift and tail set to yes
These 2 options are contradictory.
Cannot open dir to search for restart file
Using a "*" in the name of the restart file will open the current directory to search for matching file names.
Cannot open dump file
The output file for the dump command cannot be opened. Check that the path and name are correct.
Cannot open EAM potential file %s
The specified EAM potential file cannot be opened. Check that the path and name are correct.
Cannot open file %s
The specified file cannot be opened. Check that the path and name are correct.
Cannot open fix com file %s
The output file for the fix com command cannot be opened. Check that the path and name are correct.
Cannot open fix gran/diag file %s
The output file for the fix gran/diag command cannot be opened. Check that the path and name are correct.
Cannot open fix gyration file %s
Self-explanatory.
Cannot open fix msd file %s
The output file for the fix msd command cannot be opened. Check that the path and name are correct.
Cannot open fix poems file %s
The specified file cannot be opened. Check that the path and name are correct.
Cannot open fix rdf file %s
The output file for the fix rdf command cannot be opened. Check that the path and name are correct.
Cannot open fix tmd file %s
The output file for the fix tmd command cannot be opened. Check that the path and name are correct.
Cannot open gzipped file
LAMMPS is attempting to open a gzipped version of the specified file but was unsuccessful. Check that the path and name are correct.
Cannot open input script %s
Self-explanatory.
Cannot open input script %s
Self-explanatory.
Cannot open logfile
The LAMMPS log file named in a command-line argument cannot be opened. Check that the path and name are correct.
Cannot open logfile %s
The LAMMPS log file specified in the input script cannot be opened. Check that the path and name are correct.
Cannot open log.lammps
The default LAMMPS log file cannot be opened. Check that the directory you are running in allows for files to be created.
Cannot open pair_write file
The specified output file for pair energies and forces cannot be opened. Check that the path and name are correct.
Cannot open restart file %s
Self-explanatory.
Cannot open screen file
The screen file specified as a command-line argument cannot be opened. Check that the directory you are running in allows for files to be created.
Cannot open universe log file
For a multi-partition run, the master log file cannot be opened. Check that the directory you are running in allows for files to be created.
Cannot open universe screen file
For a multi-partition run, the master screen file cannot be opened. Check that the directory you are running in allows for files to be created.
Cannot read_data after simulation box is defined
The read_data command cannot be used after a read_data, read_restart, or create_box command.
Cannot read_data until atom_style is defined
Self-explanatory.
Cannot read_restart after simulation box is defined
The read_restart command cannot be used after a read_data, read_restart, or create_box command.
Cannot redefine variable as a different style
The variable was already used as a different style variable.
Cannot replicate 2d simulation in z dimension
The replicate command cannot replicate a 2d simulation in the z dimension.
Cannot replicate with fixes that store atom quantities
Either fixes are defined that create and store atom-based vectors or a restart file was read which included atom-based vectors for fixes. The replicate command cannot duplicate that information for new atoms. You should use the replicate command before fixes are applied to the system.
Cannot run 2d simulation with nonperiodic Z dimension
Use the boundary command to make the z dimension periodic in order to run a 2d simulation.
Cannot set both respa pair and inner/middle/outer
In the rRESPA integrator, you must compute pairwise potentials either all together (pair), or in pieces (inner/middle/outer). You can't do both.
Cannot set dipole for this atom style
This atom style does not support dipole settings for each atom type.
Cannot set dump_modify flush for dump xtc
Self-explanatory.
Cannot set mass for this atom style
This atom style does not support mass settings for each atom type. Instead they are defined on a per-atom basis in the data file.
Cannot set respa middle without inner/outer
In the rRESPA integrator, you must define both a inner and outer setting in order to use a middle setting.
Cannot set this attribute for this atom style
The attribute being set does not exist for the defined atom style.
Cannot use atom style granular with chosen thermo settings
Cannot output temperature or pressure with atom style granular.
Cannot use delete_atoms unless atoms have IDs
Your atoms do not have IDs, so the delete_atoms command cannot be used.
Cannot use delete_bonds with non-molecular system
Your choice of atom style does not have bonds.
Cannot use dump bond with non-molecular system
Your choice of atom style does not have bonds.
Cannot use Ewald with 2d simulation
The kspace style ewald cannot be used in 2d simulations. You can use 2d Ewald in a 3d simulation; see the kspace_modify command.
Cannot use fix gravity vector with atom style granular
Self-explanatory.
Cannot use fix nph with no per-type mass defined
The defined atom style uses per-atom mass, not per-type mass.
Cannot use fix npt with no per-type mass defined
The defined atom style uses per-atom mass, not per-type mass.
Cannot zero momentum of 0 atoms
The collection of atoms for which momentum is being computed has no atoms.
Cannot use fix nvt with no per-type mass defined
The defined atom style uses per-atom mass, not per-type mass.
Cannot use fix poems with atom style granular
This fix is not yet enabled for this atom style.
Cannot use fix rigid with atom style granular
This fix is not yet enabled for this atom style.
Cannot use fix shake with non-molecular system
Your choice of atom style does not have bonds.
Cannot use nonperiodic boundaries with Ewald
For kspace style ewald, all 3 dimensions must have periodic boundaries unless you use the kspace_modify command to define a 2d slab with a non-periodic z dimension.
Cannot use nonperiodic boundaries with PPPM
For kspace style pppm, All 3 dimensions must have periodic boundaries unless you use the kspace_modify command to define a 2d slab with a non-periodic z dimension.
Cannot use pair tail corrections with 2d simulations
The correction factors are only currently defined for 3d systems.
Cannot use PPPM with 2d simulation
The kspace style pppm cannot be used in 2d simulations. You can use 2d PPPM in a 3d simulation; see the kspace_modify command.
Cannot use region INF when box does not exist
Regions that extend to the box boundaries can only be used after the create_box command has been used.
Cannot use rRESPA with full neighbor lists
Defined pair style uses full neighbor lists (as opposed to half neighbor lists), which are incompatible with the current implementation of rRESPA.
Cannot use vectors in variables unless atom map exists
Vectors require an atom map to be able to lookup the vector index. Only atom styles with molecular information creat a global map.
Cannot use velocity create loop all unless atoms have IDs
Atoms in the simulation to do not have IDs, so this style of velocity creation cannot be performed.
Cannot use velocity create loop all with non-contiguous atom IDs
Atoms in the simulation to do not have consecutive IDs, so this style of velocity creation cannot be performed.
Command-line variable already exists
Cannot use the -var command-line option to define the same variable more than once.
Could not create 3d FFT plan
The FFT setup in pppm failed.
Could not create 3d remap plan
The FFT setup in pppm failed.
Could not find delete_atoms group ID
Group ID used in the delete_atoms command does not exist.
Could not find delete_atoms region ID
Region ID used in the delete_atoms command does not exist.
Could not find displace_atoms group ID
A group ID used in the displace_atoms command does not exist.
Cound not find dump_modify ID
A dump ID used in the dump_modify command does not exist.
Could not find dump group ID
A group ID used in the dump command does not exist.
Could not find fix group ID
A group ID used in the fix command does not exist.
Could not find fix_modify ID
A fix ID used in the fix_modify command does not exist.
Could not find fix_modify temperature ID
A temperature ID used in the fix_modify command does not exist.
Could not find fix poems group ID
A group ID used in the fix poems command does not exist.
Could not find fix recenter group ID
A group ID used in the fix recenter command does not exist.
Could not find fix rigid group ID
A group ID used in the fix rigid command does not exist.
Could not find fix spring couple group ID
Self-explanatory.
Could not find temp_modify ID
A temperature ID used in the temp_modify command does not exist.
Could not find temperature group ID
A group ID used in the temperature command does not exist.
Could not find thermo temperature ID
A temperature ID used in the thermo custom style does not exist.
Could not find thermo_modify temperature ID
A temperature ID used in the thermo_modify command does not exist.
Could not find undump ID
A dump ID used in the undump command does not exist.
Could not find unfix ID
A fix ID used in the unfix command does not exist.
Could not find velocity group ID
A group ID used in the velocity command does not exist.
Could not find velocity temperature ID
A temperature ID used in the velocity command does not exist.
Create_atoms command before simulation box is defined
The create_atoms command cannot be used before a read_data, read_restart, or create_box command.
Create_atoms region ID does not exist
A region ID used in the create_atoms command does not exist.
Create_box region must be of type inside
The region used in the create_box command must not be an "outside" region. See the region command for details.
Create_box region ID does not exist
A region ID used in the create_box command does not exist.
Cyclic loop in joint connections
Fix poems cannot (yet) work with coupled bodies whose joints connect the bodies in a ring (or cycle).
Delete_atoms command before simulation box is defined
The delete_atoms command cannot be used before a read_data, read_restart, or create_box command.
Delete_atoms cutoff > neighbor cutoff
Cannot use a cutoff with delete_atoms overlap that is larger than the force cutoff + neighbor skin.
Delete_bonds command before simulation box is defined
The delete_bonds command cannot be used before a read_data, read_restart, or create_box command.
Delete_bonds command with no atoms existing
No atoms are yet defined so the delete_bonds command cannot be used.
Did not assign all atoms correctly
Atoms read in from a data file were not assigned correctly to processors. This is likely due to some atom coordinates being outside a non-periodic simulation box.
Did not find keyword in table file
Keyword used in pair_coeff command was not found in table file.
Did not find fix shake partner info
Could not find bond partners implied by fix shake command. This error can be triggered if the delete_bonds command was used before fix shake, and it removed bonds without resetting the 1-2, 1-3, 1-4 weighting list via the special keyword.
Dihedral atoms %d %d %d %d missing on proc %d at step %d
One or more of 4 atoms needed to compute a particular dihedral are missing on this processor. Typically this is because the pairwise cutoff is set too short or the dihedral has blown apart and an atom is too far away.
Dihedral atom missing in delete_bonds
The delete_bonds command cannot find one or more atoms in a particular dihedral on a particular processor. The pairwise cutoff is too short or the atoms are too far apart to make a valid dihedral.
Dihedral atom missing in set command
The set command cannot find one or more atoms in a particular dihedral on a particular processor. The pairwise cutoff is too short or the atoms are too far apart to make a valid dihedral.
Dihedral_coeff command before dihedral_style is defined
Coefficients cannot be set in the data file or via the dihedral_coeff command until an dihedral_style has been assigned.
Dihedral_coeff command before simulation box is defined
The dihedral_coeff command cannot be used before a read_data, read_restart, or create_box command.
Dihedral_coeff command when no dihedrals allowed
The chosen atom style does not allow for dihedrals to be defined.
Dihedral coeff for hybrid has invalid style
Dihedral style hybrid uses another dihedral style as one of its coefficients. The dihedral style used in the dihedral_coeff command or read from a restart file is not recognized.
Dihedral coeffs are not set
No dihedral coefficients have been assigned in the data file or via the dihedral_coeff command.
Dihedrals assigned incorrectly
Dihedrals read in from the data file were not assigned correctly to atoms. This means there is something invalid about the topology definitions.
Dihedrals defined but no dihedral types
The data file header lists dihedrals but no dihedral types.
Dihedral style hybrid cannot have hybrid as an argument
Self-explanatory.
Dihedral style hybrid cannot use same dihedral style twice
Self-explanatory.
Dimension command after simulation box is defined
The dimension command cannot be used after a read_data, read_restart, or create_box command.
Dipole command before simulation box is defined
The dipole command cannot be used before a read_data, read_restart, or create_box command.
Displace_atoms command before simulation box is defined
The displace_atoms command cannot be used before a read_data, read_restart, or create_box command.
Dump dcd must use group all
Self-explanatory.
Dump dcd of non-matching # of atoms
Every snapshot written by dump dcd must contain the same # of atoms.
Dump xtc must use group all
Self-explanatory.
Dump_modify region ID does not exist
Self-explanatory.
Dump xtc must use group all
Self-explanatory.
Failed to allocate %d bytes for array %s
Your LAMMPS simulation has run out of memory. You need to run a smaller simulation or on more processors.
Failed to reallocate %d bytes for array %s
Your LAMMPS simulation has run out of memory. You need to run a smaller simulation or on more processors.
Fix command before simulation box is defined
The fix command cannot be used before a read_data, read_restart, or create_box command.
Fix insert region ID does not exist
A region ID used in the fix insert command does not exist.
Fix langevin period must be > 0.0
The time window for temperature relaxation must be > 0
Fix langevin region ID does not exist
Self-explanatory.
Fix msd group has no atoms
Cannot compute diffusion for no atoms.
Fix momentum group has no atoms
Self-explanatory.
Fix nph periods must be > 0.0
The time window for pressure relaxation must be > 0
Fix npt periods must be > 0.0
The time window for temperature or pressure relaxation must be > 0
Fix nvt period must be > 0.0
The time window for temperature relaxation must be > 0
Fix orient/fcc file open failed
The fix orient/fcc command could not open a specified file.
Fix orient/fcc file read failed
The fix orient/fcc command could not read the needed parameters from a specified file.
Fix orient/fcc found self twice
The neighbor lists used by fix orient/fcc are messed up. If this error occurs, it is likely a bug, so send an email to the developers.
Fix rdf requires a pair style be defined
Cannot use the rdf fix unless a pair style with a cutoff has been defined.
Fix recenter group has no atoms
Self-explanatory.
Fix temp/rescale region ID does not exist
Self-explanatory.
Fix tmd must come after integration fixes
Any fix tmd command must appear in the input script after all time integration fixes (nve, nvt, npt). See the fix tmd documentation for details.
Fix wall/gran can only be used with granular pair style
Self-explanatory.
Found no restart file matching pattern
When using a "*" in the restart file name, no matching file was found.
Granular pair styles do not use pair_coeff settings
The pair_coeff command cannot be used with granular force fields.
Gravity must point in -y to use with fix insert in 2d
Gravity must be pointing "down" in a 2d box.
Gravity must point in -z to use with fix insert in 3d
Gravity must be pointing "down" in a 3d box, i.e. theta = 180.0.
Group command before simulation box is defined
The group command cannot be used before a read_data, read_restart, or create_box command.
Group ID does not exist
A group ID used in the group command does not exist.
Group region ID does not exist
A region ID used in the group command does not exist.
Illegal ... command
Self-explanatory. Check the input script syntax and compare to the documentation for the command. You can use -echo screen as a command-line option when running LAMMPS to see what is the offending line.
Improper atoms %d %d %d %d missing on proc %d at step %d
One or more of 4 atoms needed to compute a particular improper are missing on this processor. Typically this is because the pairwise cutoff is set too short or the improper has blown apart and an atom is too far away.
Improper atom missing in delete_bonds
The delete_bonds command cannot find one or more atoms in a particular improper on a particular processor. The pairwise cutoff is too short or the atoms are too far apart to make a valid improper.
Improper atom missing in set command
The set command cannot find one or more atoms in a particular improper on a particular processor. The pairwise cutoff is too short or the atoms are too far apart to make a valid improper.
Improper_coeff command before improper_style is defined
Coefficients cannot be set in the data file or via the improper_coeff command until an improper_style has been assigned.
Improper_coeff command before simulation box is defined
The improper_coeff command cannot be used before a read_data, read_restart, or create_box command.
Improper_coeff command when no impropers allowed
The chosen atom style does not allow for impropers to be defined.
Improper coeff for hybrid has invalid style
Improper style hybrid uses another improper style as one of its coefficients. The improper style used in the improper_coeff command or read from a restart file is not recognized.
Improper coeffs are not set
No improper coefficients have been assigned in the data file or via the improper_coeff command.
Impropers assigned incorrectly
Impropers read in from the data file were not assigned correctly to atoms. This means there is something invalid about the topology definitions.
Impropers defined but no improper types
The data file header lists improper but no improper types.
Improper style hybrid cannot have hybrid as an argument
Self-explanatory.
Improper style hybrid cannot use same improper style twice
Self-explanatory.
Inconsistent dipole settings for some atoms
Dipole moment must be 0 for non-dipole type atoms. Dipole moment must be set for dipole type atoms.
Incorrect args for angle coefficients
Self-explanatory. Check the input script or data file.
Incorrect args for bond coefficients
Self-explanatory. Check the input script or data file.
Incorrect args for dihedral coefficients
Self-explanatory. Check the input script or data file.
Incorrect args for improper coefficients
Self-explanatory. Check the input script or data file.
Incorrect args for pair coefficients
Self-explanatory. Check the input script or data file.
Incorrect atom format in data file
Number of values per atom line in the data file is not consistent with the atom style.
Incorrect boundaries with slab Ewald
Must have periodic x,y dimensions and non-periodic z dimension to use 2d slab option with Ewald.
Incorrect boundaries with slab PPPM
Must have periodic x,y dimensions and non-periodic z dimension to use 2d slab option with PPPM.
Incorrect format in TMD target file
Format of file read by fix tmd command is incorrect.
Incorrect multiplicity arg for dihedral coefficients
Self-explanatory. Check the input script or data file.
Incorrect sign arg for dihedral coefficients
Self-explanatory. Check the input script or data file.
Incorrect weight arg for dihedral coefficients
Self-explanatory. Check the input script or data file.
Insertion region extends outside simulation box
Region specified with fix insert command extends outside the global simulation box.
Insufficient Jacobi rotations for POEMS body
Eigensolve for rigid body was not sufficiently accurate.
Insufficient Jacobi rotations for rigid body
Eigensolve for rigid body was not sufficiently accurate.
Invalid angle style
The choice of angle style is unknown.
Invalid angle type in Angles section of data file
Angle type must be positive integer and within range of specified angle types.
Invalid angle type index for fix shake
Self-explanatory.
Invalid atom ID in Angles section of data file
Atom IDs must be positive integers and within range of defined atoms.
Invalid atom ID in Atoms section of data file
Atom IDs must be positive integers.
Invalid atom ID in Bonds section of data file
Atom IDs must be positive integers and within range of defined atoms.
Invalid atom ID in Dihedrals section of data file
Atom IDs must be positive integers and within range of defined atoms.
Invalid atom ID in Impropers section of data file
Atom IDs must be positive integers and within range of defined atoms.
Invalid atom ID in Velocities section of data file
Atom IDs must be positive integers and within range of defined atoms.
Invalid atom mass for fix shake
Mass specified in fix shake command must be > 0.0.
Invalid atom style
The choice of atom style is unknown.
Invalid atom type in Atoms section of data file
Atom types must range from 1 to specified # of types.
Invalid atom type in neighbor exclusion list
Atom types must range from 1 to Ntypes inclusive.
Invalid atom type index for fix shake
Atom types must range from 1 to Ntypes inclusive.
Invalid atom types in fix rdf command
Atom types must range from 1 to Ntypes inclusive.
Invalid atom types in pair_write command
Atom types must range from 1 to Ntypes inclusive.
Invalid bond style
The choice of bond style is unknown.
Invalid bond type in Bonds section of data file
Bond type must be positive integer and within range of specified bond types.
Invalid bond type index for fix shake
Self-explanatory. Check the fix shake command in the input script.
Invalid coeffs for this angle style
Cannot set class 2 coeffs in data file for this angle style.
Invalid coeffs for this dihedral style
Cannot set class 2 coeffs in data file for this dihedral style.
Invalid coeffs for this improper style
Cannot set class 2 coeffs in data file for this improper style.
Invalid command-line argument
One or more command-line arguments is invalid. Check the syntax of the command you are using to launch LAMMPS.
Invalid cutoffs in pair_write command
Inner cutoff must be larger than 0.0 and less than outer cutoff.
Invalid data file section: Angle Coeffs
Atom style does not allow angles.
Invalid data file section: AngleAngle Coeffs
Atom style does not allow impropers.
Invalid data file section: AngleAngleTorsion Coeffs
Atom style does not allow dihedrals.
Invalid data file section: AngleTorsion Coeffs
Atom style does not allow dihedrals.
Invalid data file section: Angles
Atom style does not allow angles.
Invalid data file section: Bond Coeffs
Atom style does not allow bonds.
Invalid data file section: BondAngle Coeffs
Atom style does not allow angles.
Invalid data file section: BondBond Coeffs
Atom style does not allow angles.
Invalid data file section: BondBond13 Coeffs
Atom style does not allow dihedrals.
Invalid data file section: Bonds
Atom style does not allow bonds.
Invalid data file section: Dihedral Coeffs
Atom style does not allow dihedrals.
Invalid data file section: Dihedrals
Atom style does not allow dihedrals.
Invalid data file section: EndBondTorsion Coeffs
Atom style does not allow dihedrals.
Invalid data file section: Improper Coeffs
Atom style does not allow impropers.
Invalid data file section: Impropers
Atom style does not allow impropers.
Invalid data file section: MiddleBondTorsion Coeffs
Atom style does not allow dihedrals.
Invalid dihedral style
The choice of dihedral style is unknown.
Invalid dihedral type in Dihedrals section of data file
Dihedral type must be positive integer and within range of specified dihedral types.
Invalid dump dcd filename
Filenames used with the dump dcd style cannot be binary or compressed or cause multiple files to be written.
Invalid dump frequency
Dumps frequency must be 1 or greater.
Invalid dump_modify threshhold operator
Operator keyword used for threshhold specification in not recognized.
Invalid dump style
The choice of dump style is unknown.
Invalid dump xtc filename
Filenames used with the dump xtc style cannot be binary or compressed or cause multiple files to be written.
Invalid dump xyz filename
Filenames used with the dump xyz style cannot be binary or cause files to be written by each processor.
Invalid group ID in neigh_modify command
A group ID used in the neigh_modify command does not exist.
Invalid fix style
The choice of fix style is unknown.
Invalid flag in header of restart file
Value read from beginning of restart file is not recognized.
Invalid improper style
The choice of improper style is unknown.
Invalid improper type in Impropers section of data file
Improper type must be positive integer and within range of specified improper types.
Invalid keyword in dump custom command
One or more attribute keywords are not recognized.
Invalid keyword in pair table parameters
Keyword used in list of table parameters is not recognized.
Invalid keyword in thermo_style command
One or more attribute keywords are not recognized.
Invalid keyword in variable equal command
One or more attribute keywords are not recognized.
Invalid kspace style
The choice of kspace style is unknown.
Invalid natoms for dump dcd
Natoms is initially 0 which is not valid for the dump dcd style. Natoms must be constant for the duration of the simulation.
Invalid natoms for dump xtc
Natoms is initially 0 which is not valid for the dump xtc style.
Invalid natoms for dump xyz
Natoms is initially 0 which is not valid for the dump xyz style.
Invalid order of forces within respa levels
For respa, ordering of force computations within respa levels must obey certain rules. E.g. bonds cannot be compute less frequently than angles, pairwise forces cannot be computed less frequently than kspace, etc.
Invalid pair style
The choice of pair style is unknown.
Invalid pair table cutoff
Cutoffs in pair_coeff command are not valid with read-in pair table.
Invalid pair table length
Length of read-in pair table is invalid
Invalid random number seed in set command
Random number seed must be > 0.
Invalid region style
The choice of region style is unknown.
Invalid style in pair_write command
Self-explanatory. Check the input script.
Invalid temperature style
The choice of temperature style is unknown.
Invalid type for dipole set
Dipole command must set a type from 1-N where N is the number of atom types.
Invalid type for mass set
Mass command must set a type from 1-N where N is the number of atom types.
Invalid type in set command
Type used in set command must be from 1-N where N is the number of atom types (bond types, angle types, etc).
Invalid variable in next command
Next command in input script must set variables from "a" to "z".
Invalid variable name
Variable name used in an input script line is invalid.
Invalid variable style with next command
Variable styles equal and world cannot be used in a next command.
Invalid vector in variable equal command
One or more vector names are not recognized.
Invoked pair single on pair style none
A command (e.g. a dump) attempted to invoke the single() function on a pair style none, which is illegal. You are probably attempting to compute per-atom quantities with an undefined pair style.
KSpace style has not yet been set
Cannot use kspace_modify command until a kspace style is set.
KSpace style is incompatible with Pair style
Setting a kspace style requires that a pair style with a long-range Coulombic component be selected.
Label wasn't found in input script
Self-explanatory.
Lattice style incompatible with dimension
2d simulation can use sq, sq2, or hex lattice. 3d simulation can use sc, bcc, or fcc lattice.
Lost atoms via displacement: original %.15g current %.15g
Moving atoms via the displace_atoms command lost one or more atoms.
Lost atoms: original %.15g current %.15g
A thermodynamic computation has detected lost atoms.
Marsaglia RNG cannot use 0 seed
The random number generator use for the fix langevin command cannot use 0 as an initial seed.
Mass command before simulation box is defined
The mass command cannot be used before a read_data, read_restart, or create_box command.
Minimize command before simulation box is defined
The minimize command cannot be used before a read_data, read_restart, or create_box command.
Min_style command before simulation box is defined
The min_style command cannot be used before a read_data, read_restart, or create_box command.
More than one freeze fix
You can only define one freeze fix.
More than one shake fix
You can only define one SHAKE fix.
Must define angle_style before Angle Coeffs
Must use an angle_style command before reading a data file that defines Angle Coeffs.
Must define angle_style before BondAngle Coeffs
Must use an angle_style command before reading a data file that defines Angle Coeffs.
Must define angle_style before BondBond Coeffs
Must use an angle_style command before reading a data file that defines Angle Coeffs.
Must define bond_style before Bond Coeffs
Must use a bond_style command before reading a data file that defines Bond Coeffs.
Must define dihedral_style before AngleAngleTorsion Coeffs
Must use a dihedral_style command before reading a data file that defines AngleAngleTorsion Coeffs.
Must define dihedral_style before AngleTorsion Coeffs
Must use a dihedral_style command before reading a data file that defines AngleTorsion Coeffs.
Must define dihedral_style before BondBond13 Coeffs
Must use a dihedral_style command before reading a data file that defines BondBond13 Coeffs.
Must define dihedral_style before Dihedral Coeffs
Must use a dihedral_style command before reading a data file that defines Dihedral Coeffs.
Must define dihedral_style before EndBondTorsion Coeffs
Must use a dihedral_style command before reading a data file that defines EndBondTorsion Coeffs.
Must define dihedral_style before MiddleBondTorsion Coeffs
Must use a dihedral_style command before reading a data file that defines MiddleBondTorsion Coeffs.
Must define improper_style before AngleAngle Coeffs
Must use an improper_style command before reading a data file that defines AngleAngle Coeffs.
Must define improper_style before Improper Coeffs
Must use an improper_style command before reading a data file that defines Improper Coeffs.
Must define pair_style before Pair Coeffs
Must use a pair_style command before reading a data file that defines Pair Coeffs.
Must have more than one processor partition to temper
Cannot use the temper command with only one processor partition. Use the -partition command-line option.
Must read Atoms before Angles
The Atoms section of a data file must come before an Angles section.
Must read Atoms before Bonds
The Atoms section of a data file must come before a Bonds section.
Must read Atoms before Dihedrals
The Atoms section of a data file must come before a Dihedrals section.
Must read Atoms before Impropers
The Atoms section of a data file must come before an Impropers section.
Must read Atoms before Velocities
The Atoms section of a data file must come before a Velocities section.
Must set both respa inner and outer
Cannot use just the inner or outer option with repsa without using the other.
Must specify a region in fix insert
Self-explanatory.
Must use a block or cylinder region with fix insert
Self-explanatory.
Must use a block region with fix insert for 2d simulations
Self-explanatory.
Must use a molecular atom style with fix poems molecule
Self-explanatory.
Must use a molecular atom style with fix rigid molecule
Self-explanatory.
Must use atom style dipole with chosen thermo settings
A thermo quantity being printed can only be computed if the atom style includes dipole quantities.
Must use a z-axis cylinder with fix insert
The axis of the cylinder region used with the fix insert command must be oriented along the z dimension.
Must use atom style dpd with pair style dpd
Self-explanatory.
Must use atom style granular with pair style granular
Self-explanatory.
Must use atom style granular with chosen thermo settings
If granular thermo info is to be output, must use atom style granular.
Must use atom style granular with granular thermo output
If atom style is granular, must use thermo style granular or custom.
Must use charged atom style with fix efield
The atom style being used does not allow atoms to have assigned charges. Hence it will not work with this fix which generates a force due to an E-field acting on charge.
Must use charged atom style with this pair style
The atom style being used does not allow atoms to have assigned charges. Hence it will not work with this choice of pair style.
Must use fix freeze with atom style granular
Self-explanatory.
Must use fix gran/diag with atom style granular
Self-explanatory.
Must use fix gran/diag with granular pair style
Self-explanatory.
Must use fix gravity chute with atom style granular
Self-explanatory.
Must use fix gravity spherical with atom style granular
Self-explanatory.
Must use fix gravity gradient with atom style granular
Self-explanatory.
Must use fix gravity with fix insert
Insertion of granular particles must be done under the influence of gravity.
Must use fix insert with atom style granular
Self-explanatory.
Must use fix nve/gran with atom style granular
Self-explanatory.
Must use fix wall/gran with atom style granular
Self-explanatory.
Must use -in switch with multiple partitions
A multi-partition simulation cannot read the input script from stdin. The -in command-line option must be used to specify a file.
Must use lj units with atom style granular
Self-explanatory.
Must use molecular atom style with neigh_modify exclude molecule
Self-explanatory.
Must use region with side = in with fix insert
Self-explanatory.
Must use special bonds = 1,1,1 with bond style quartic
The settings for the special_bonds command must be set as indicated when using bond style quartic.
Needed topology not in data file
The header of the data file indicated that bonds or angles or dihedrals or impropers would be included, but they were not present.
Neighbor delay must be 0 or multiple of every setting
The delay and every parameters set via the neigh_modify command are inconsistent. If the delay setting is non-zero, then it must be a multiple of the every setting.
Neighbor list overflow, boost neigh_modify one or page
There are too many neighbors of a single atom. Use the neigh_modify command to increase the neighbor page size and the max number of neighbors allowed for one atom.
Newton bond change after simulation box is defined
The newton command cannot be used to change the newton bond value after a read_data, read_restart, or create_box command.
No angles allowed with this atom style
Self-explanatory. Check data file.
No atoms in data file
The header of the data file indicated that atoms would be included, but they were not present.
No bonds allowed with this atom style
Self-explanatory. Check data file.
No dihedrals allowed with this atom style
Self-explanatory. Check data file.
No dump custom arguments specified
The dump custom command requires that atom quantities be specified to output to dump file.
No impropers allowed with this atom style
Self-explanatory. Check data file.
No rigid bodies defined by fix rigid
Self-explanatory.
Non integer # of swaps in temper command
Swap frequency in temper command must evenly divide the total # of timesteps.
Non-orthogonal lattice vectors
Self-explanatory.
One or zero atoms in rigid body
Any rigid body defined by the fix rigid command must contain 2 or more atoms.
One or more atoms belong to multiple rigid bodies
Two or more rigid bodies defined by the fix rigid command cannot contain the same atom.
Orientation vectors are not right-handed
The 3 vectors defined by the orient command must form a right-handed coordinate system.
Out of range atoms - cannot compute PPPM
One or more atoms are attempting to map their charge to a PPPM grid point that is not owned by a processor. This is usually because an atom has moved to far in a single timestep.
Pair distance < table inner cutoff
Two atoms are closer together than the pairwise table allows.
Pair distance > table outer cutoff
Two atoms are further apart than the pairwise table allows.
Pair table parameters did not set N
List of pair table parameters must include N setting.
PPPM grid is too large
The global PPPM grid is larger than OFFSET in one or more dimensions. OFFSET is currently set to 4096. You likely need to decrease the requested precision.
PPPM order cannot be greater than %d
Self-explanatory.
PPPM stencil extends too far, reduce PPPM order
The grid points that atom charge are mapped to cannot extend further than one neighbor processor away. Reducing the PPPM order via the kspace_modify command will reduce the stencil distance.
Pair coeff for hybrid has invalid style
Style in pair coeff must have been listed in pair_style command.
Pair cutoff < Respa interior cutoff
One or more pairwise cutoffs are too short to use with the specified rRESPA cutoffs.
Pair inner cutoff < Respa interior cutoff
One or more pairwise cutoffs are too short to use with the specified rRESPA cutoffs.
Pair inner cutoff >= Pair outer cutoff
The specified cutoffs for the pair style are inconsistent.
Pair style does not support bond_style quartic
The pair style does not have a single() function, so it can not be invoked by bond_style quartic.
Pair style does not support dumping per-atom energy
The pair style does not have a single() function, so it can not be invoked by the dump command.
Pair style does not support dumping per-atom stress
The pair style does not have a single() function, so it can not be invoked by the dump command.
Pair style does not support pair_write
The pair style does not have a single() function, so it can not be invoked by the pair_write command.
Pair style does not support rRESPA inner/middle/outer
You are attempting to use rRESPA options with a pair style that does not support them.
Pair style granular with history requires atoms have IDs
Atoms in the simulation do not have IDs, so history effects cannot be tracked by the granular pair potential.
Pair style hybrid cannot have hybrid as an argument
Self-explanatory. Check the input script.
Pair style hybrid cannot use same pair style twice
The sub-style arguments of pair_style hybrid cannot be duplicated. Check the input script.
Pair style is incompatible with DihedralCharmm
When using a dihedral style charmm, a pair style with a CHARMM component must also be selected, so that 1-4 pairwise coefficients are specified.
Pair style is incompatible with KSpace style
If a pair style with a long-range Coulombic component is selected, then a kspace style must also be used.
Pair style lj/cut/coul/long/tip4p requires atom IDs
There are no atom IDs defined in the system and the TIP4P potential requires them to find O,H atoms with a water molecule.
Pair style lj/cut/coul/long/tip4p requires newton pair on
This is because the computation of constraint forces within a water molecule adds forces to atoms owned by other processors.
Pair table cutoffs must all be equal to use with KSpace
When using pair style table with a long-range KSpace solver, the cutoffs for all atom type pairs must all be the same, since the long-range solver starts at that cutoff.
Pair_coeff command before pair_style is defined
Self-explanatory.
Pair_coeff command before simulation box is defined
The pair_coeff command cannot be used before a read_data, read_restart, or create_box command.
Pair_modify command before pair_style is defined
Self-explanatory.
Pair_style granular command before simulation box is defined
This pair style cannot be used before a simulation box is defined.
Pair_write command before pair_style is defined
Self-explanatory.
POEMS fix must come before NPT/NPH fix
NPT/NPH fix must be defined in input script after all poems fixes, else the fix contribution to the pressure virial is incorrect.
Potential with shear history requires newton pair off
Granular potentials that include shear history effects can only be run with a newton setting where pairwise newton is "off".
Proc grid in z != 1 for 2d simulation
There cannot be more than 1 processor in the z dimension of a 2d simulation.
Processor partitions are inconsistent
The total number of processors in all partitions must match the number of processors LAMMPS is running on.
Processors command after simulation box is defined
The processors command cannot be used after a read_data, read_restart, or create_box command.
Quaternion creation numeric error
A numeric error occurred in the creation of a rigid body by the fix rigid command.
Quotes in a single arg
A single word should not be quoted in the input script; only a set of words with intervening spaces should be quoted.
R0 < 0 for fix spring command
Equilibrium spring length is invalid.
Region union region ID does not exist
One or more of the region IDs specified by the region union command does not exist.
Replacing a fix, but new style != old style
A fix ID can be used a 2nd time, but only if the style matches the previous fix. In this case it is assumed you with to reset a fix's parameters. This error may mean you are mistakenly re-using a fix ID when you do not intend to.
Replicate command before simulation box is defined
The replicate command cannot be used before a read_data, read_restart, or create_box command.
Replicate did not assign all atoms correctly
Atoms replicated by the replicate command were not assigned correctly to processors. This is likely due to some atom coordinates being outside a non-periodic simulation box.
Requested atom types in EAM setfl file do not exist
Atom type specified in pair_style eam command does not match number of types in setfl potential file.
Respa inner cutoffs are invalid
The first cutoff must be <= the second cutoff.
Respa levels must be >= 1
Self-explanatory.
Respa middle cutoffs are invalid
The first cutoff must be <= the second cutoff.
Respa not allowed with atom style granular
Respa cannot be used with the granular atom style.
Reuse of dump ID
A dump ID cannot be used twice.
Reuse of region ID
A region ID cannot be used twice.
Reuse of temperature ID
A temperature ID cannot be used twice.
Rigid body has degenerate moment of inertia
Fix poems will only work with bodies (collections of atoms) that have non-zero principal moments of inertia. This means they must be 3 or more non-colinear atoms, even with joint atoms removed.
Rigid fix must come before NPT/NPH fix
NPT/NPH fix must be defined in input script after all rigid fixes, else the rigid fix contribution to the pressure virial is incorrect.
Run command before simulation box is defined
The run command cannot be used before a read_data, read_restart, or create_box command.
Run command upto value is before current timestep
Self-explanatory.
Run command start value is after start of run
Self-explanatory.
Run command stop value is before end of run
Self-explanatory.
Run_style command before simulation box is defined
The run_style command cannot be used before a read_data, read_restart, or create_box command.
Set command before simulation box is defined
The set command cannot be used before a read_data, read_restart, or create_box command.
Set command with no atoms existing
No atoms are yet defined so the set command cannot be used.
Shake angles have different bond types
All 3-atom angle-constrained SHAKE clusters specified by the fix shake command that are the same angle type, must also have the same bond types for the 2 bonds in the angle.
Shake atoms %d %d %d %d missing on proc %d at step %d
The 4 atoms in a single shake cluster specified by the fix shake command are not all accessible to a processor. This probably means an atom has moved too far.
Shake atoms %d %d %d missing on proc %d at step %d
The 3 atoms in a single shake cluster specified by the fix shake command are not all accessible to a processor. This probably means an atom has moved too far.
Shake atoms %d %d missing on proc %d at step %d
The 2 atoms in a single shake cluster specified by the fix shake command are not all accessible to a processor. This probably means an atom has moved too far.
Shake cluster of more than 4 atoms
A single cluster specified by the fix shake command can have no more than 4 atoms.
Shake clusters are connected
A single cluster specified by the fix shake command must have a single central atom with up to 3 other atoms bonded to it.
Shake determinant = 0.0
The determinant of the matrix being solved for a single cluster specified by the fix shake command is numerically invalid.
Shake fix must come before NPT/NPH fix
NPT fix must be defined in input script after SHAKE fix, else the SHAKE fix contribution to the pressure virial is incorrect.
Substitution for undefined variable
The variable specified with a $ symbol in an input script command has not been previously defined with a variable command.
Target T for fix nvt cannot be 0.0
Self-explanatory.
Target T for fix npt cannot be 0.0
Self-explanatory.
Temperature region ID does not exist
The region ID specified in the temperature command does not exist.
Temper command before simulation box is defined
The temper command cannot be used before a read_data, read_restart, or create_box command.
Tempering fix ID is not defined
The fix ID specified by the temper command does not exist.
Tempering fix is not valid
The fix specified by the temper command is not one that controls temperature (nvt or langevin).
Thermodynamics not computed on tempering swap steps
The thermo command must insure that thermodynamics (including energy) is computed on the timesteps that tempering swaps are attempted.
Thermodynamics must compute PE for temper
The thermo style must insure that thermodynamics computations include potential energy when tempering is performed.
Thermo_style command before simulation box is defined
The thermo_style command cannot be used before a read_data, read_restart, or create_box command.
Timestep must be >= 0
Specified timestep size is invalid.
TIP4P hydrogen has incorrect atom type
The TIP4P pairwise computation found an H atom whose type does not agree with the specified H type.
TIP4P hydrogen is missing
The TIP4P pairwise computation failed to find the correct H atom within a water molecule.
TMD target file did not list all group atoms
The target file for the fix tmd command did not list all atoms in the fix group.
Too big a problem to replicate with molecular atom style
Molecular problems cannot become bigger than 2^31 atoms (or bonds, etc) when replicated, else the atom IDs and other quantities cannot be stored in 32 bit quantities.
Too few bits for lookup table
Table size specified via pair_modify command does not work with your machine's floating point representation.
Too large an atom type in create_atoms command
The atoms to be created by the create_atoms command must have a valid type.
Too many exponent bits for lookup table
Table size specified via pair_modify command does not work with your machine's floating point representation.
Too many mantissa bits for lookup table
Table size specified via pair_modify command does not work with your machine's floating point representation.
Too many groups
The maximum number of atom groups (including the "all" group) is given by MAX_GROUP in group.cpp and is 32.
Too many masses for fix shake
The fix shake command cannot list more masses than there are atom types.
Too many total bits for bitmapped lookup table
Table size specified via pair_modify command is too large. Note that a value of N generates a 2^N size table.
Too many touching neighbors - boost MAXTOUCH
A granular simulation has too many neighbors touching one atom. The MAXTOUCH parameter in fix_shear_history.cpp must be set larger and LAMMPS must be re-built.
Tree structure in joint connections
Fix poems cannot (yet) work with coupled bodies whose joints connect the bodies in a tree structure.
Unbalanced quotes in input line
No matching end double quote was found following a leading double quote.
Unexpected end of data file
LAMMPS hit the end of the data file while attempting to read a section. Something is wrong with the format of the data file.
Units command after simulation box is defined
The units command cannot be used after a read_data, read_restart, or create_box command.
Unknown atom style in restart file
The atom style stored in the restart file is not recognized by LAMMPS.
Unknown command: %s
The command is not known to LAMMPS. Check the input script.
Unknown identifier in data file: %s
A section of the data file cannot be read by LAMMPS.
Unknown section in data file: %s
The keyword for a section of the data file is not recognized by LAMMPS.
Unknown table style in pair_style command
Style of table is invalid for use with pair_style table command.
Universe variable count < # of partitions
A world-style variable must specify a number of values >= to the number of processor partitions.
Use of displace_atoms with undefined lattice
Must use lattice command with displace_atoms command if units option is set to lattice.
Use of fix indent with undefined lattice
The lattice command must be used to define a lattice before using the fix indent command.
Use of region with undefined lattice
If scale = lattice (the default) for the region command, then a lattice must first be defined via the lattice command.
Use of temperature ramp with undefined lattice
If scale = lattice (the default) for the temperature ramp command, then a lattice must first be defined via the lattice command.
Use of velocity with undefined lattice
If scale = lattice (the default) for the velocity set or velocity ramp command, then a lattice must first be defined via the lattice command.
Using variable equal keyword before simulation box is defined
Cannot use simulation domain keywords in a equal style variable definition until the simulation box has been defined.
Using variable equal keyword before initial run
Cannot use thermodynamic keywords in a equal style variable definition until a simulation run has been performed.
Variable equal group ID does not exist
Self-explanatory.
Velocity command before simulation box is defined
The velocity command cannot be used before a read_data, read_restart, or create_box command.
Velocity command with no atoms existing
A velocity command has been used, but no atoms yet exist.
Velocity ramp in z for a 2d problem
Self-explanatory.
World variable count doesn't match # of partitions
A world-style variable must specify a number of values equal to the number of processor partitions.
Write_restart command before simulation box is defined
The write_restart command cannot be used before a read_data, read_restart, or create_box command.

Warnings:

FENE bond too long: %d %g
A FENE bond has stretched dangerously far. It's interaction strength will be truncated to attempt to prevent the bond from blowing up.
FENE bond too long: %d %d %d %g
A FENE bond has stretched dangerously far. It's interaction strength will be truncated to attempt to prevent the bond from blowing up.
Fix recenter should come after all other integration fixes
Other fixes may change the position of the center-of-mass, so fix recenter should come last.
Group for fix_modify temp != fix group
The fix_modify command is specifying a temperature computation that computes a temperature on a different group of atoms than the fix itself operates on. This is probably not what you want to do.
Less insertions than requested
Less atom insertions occurred on this timestep due to the fix insert command than were scheduled. This is probably because there were too many overlaps detected.
Lost atoms: original %.15g current %.15g
A thermodynamic computation has detected lost atoms.
Mismatch between velocity and temperature groups
The temperature computation used by the velocity command will not be on the same group of atoms that velocities are being set for. This is probably not what you want.
More than one dump custom with a centro attribute
Each dump custom command that uses a per-atom centro attribute will cause a full neighbor list to be built and looped over. Thus it may be inefficient to use this attribute in multiple dump custom commands.
More than one dump custom with a stress attribute
Each dump custom command that uses a per-atom stress tensor attribute will cause the neighbor list to be looped over and inter-processor communication to be performed. Thus it may be inefficient to use these attributes in multiple dump custom commands.
More than one dump custom with an energy attribute
Each dump custom command that uses a per-atom energy attribute will cause the neighbor list to be looped over and inter-processor communication to be performed. Thus it may be inefficient to use this attribute in multiple dump custom commands.
More than one msd fix
This will be computationally inefficient.
More than one poems fix
This will be computationally inefficient and compute the fix's contribution to the virial (pressure) incorrectly.
More than one rigid fix
This will be computationally inefficient and compute the fix's contribution to the virial (pressure) incorrectly.
No fixes defined, atoms won't move
If you are not using a fix like nve, nvt, npt then atom velocities and coordinates will not be updated during timestepping.
No joints between rigid bodies, use fix rigid instead
The bodies defined by fix poems are not connected by joints. POEMS will integrate the body motion, but it would be more efficient to use fix rigid.
One or more respa levels compute no forces
This is computationally inefficient.
Replacing a fix, but new group != old group
The ID and style of a fix match for a fix you are changing with a fix command, but the new group you are specifying does not match the old group.
Replicating in a non-periodic dimension
The parameters for a replicate command will cause a non-periodic dimension to be replicated; this may cause unwanted behavior.
Resetting angle_style to restart file value
The angle style defined in the LAMMPS input script does not match that of the restart file.
Resetting bond_style to restart file value
The bond style defined in the LAMMPS input script does not match that of the restart file.
Resetting boundary settings to restart file values
The boundary settings defined in the LAMMPS input script do not match that of the restart file.
Resetting dihedral_style to restart file value
The dihedral style defined in the LAMMPS input script does not match that of the restart file.
Resetting dimension to restart file value
The dimension value defined in the LAMMPS input script does not match that of the restart file.
Resetting improper_style to restart file value
The improper style defined in the LAMMPS input script does not match that of the restart file.
Resetting newton bond to restart file value
The value of the newton setting for bonds defined in the LAMMPS input script does not match that of the restart file.
Resetting pair_style to restart file value
The pair style defined in the LAMMPS input script does not match that of the restart file.
Resetting reneighboring criteria during minimization
Minimization requires that neigh_modify settings be delay = 0, every = 1, check = yes. Since these settings were not in place, LAMMPS changed them and will restore them to their original values after the minimization.
Resetting unit_style to restart file value
The unit style defined in the LAMMPS input script does not match that of the restart file.
Restart file used different # of processors
The restart file was written out by a LAMMPS simulation running on a different number of processors. Due to round-off, the trajectories of your restarted simulation may diverge a little more quickly than if you ran on the same # of processors.
Restart file used different 3d processor grid
The restart file was written out by a LAMMPS simulation running on a different 3d grid of processors. Due to round-off, the trajectories of your restarted simulation may diverge a little more quickly than if you ran on the same # of processors.
Restart file used different newton pair setting
The restart file was written out by a LAMMPS simulation running with a different value of the newton pair setting. The new simulation will use the value from the input script.
Restart file version does not match LAMMPS version
The version of LAMMPS that wrote the restart file does not match the version of LAMMPS that is reading the restart file. Generally this shouldn't be a problem, since restart file formats won't change very often if at all. But if they do, the code will probably crash trying to read the file. Versions of LAMMPS are specified by a date.
Shake determinant < 0.0
The determinant of the quadratic equation being solved for a single cluster specified by the fix shake command is numerically suspect. LAMMPS will set it to 0.0 and continue.
System is not charge neutral, net charge = %g
The total charge on all atoms on the system is not 0.0, which is not valid for Ewald or PPPM.
Table inner cutoff >= outer cutoff
You specified an inner cutoff for a Coulombic table that is longer than the global cutoff. Probably not what you wanted.
Temperature for NPH is not for group all
User-assigned temperature to NPH fix does not compute temperature for all atoms. Since NPH computes a global pressure, the kinetic energy contribution from the temperature is assumed to also be for all atoms. Thus the pressure used by NPH could be inaccurate.
Temperature for NPH is style region
User-assigned temperature to NPH fix has style region. Since NPT computes a global pressure, the kinetic energy contribution from the temperature is assumed to also be for all atoms. Thus the pressure used by NPT could be inaccurate.
Temperature for NPT is not for group all
User-assigned temperature to NPT fix does not compute temperature for all atoms. Since NPT computes a global pressure, the kinetic energy contribution from the temperature is assumed to also be for all atoms. Thus the pressure used by NPT could be inaccurate.
Temperature for NPT is style region
User-assigned temperature to NPT fix has style region. Since NPT computes a global pressure, the kinetic energy contribution from the temperature is assumed to also be for all atoms. Thus the pressure used by NPT could be inaccurate.
Temperature for NVT is style region
User-assigned temperature to NVT fix has style region. Since NVT is a Nose/Hoover formulation that tracks average properties of a collection of atoms over time, it may be inaccurate to do this if the atoms in the region change.
Temperature for temp/rescale is style region
User-assigned temperature to temp/rescale fix has style region, but the temp/rescale fix did not specify a region. This means the temperature may be computed on a different set of atoms than are rescaled.
Temperature for thermo pressure is not for group all
User-assigned temperature to thermo via the thermo_modify command does not compute temperature for all atoms. Since thermo computes a global pressure, the kinetic energy contribution from the temperature is assumed to also be for all atoms. Thus the pressure printed by thermo could be inaccurate.
Temperature for thermo pressure is style region
User-assigned temperature to thermo via the thermo_modify command has style region. Since thermo computes a global pressure, the kinetic energy contribution from the temperature is assumed to also be for all atoms. Thus the pressure printed by thermo could be inaccurate.
Using pair tail corrections with nonperiodic system
This is probably a bogus thing to do, since tail corrections are computed by integrating the density of a periodic system out to infinity.
Using variable equal keyword with non-current thermo
The variable expression is being evaluated with a thermodynamic quantity on a timestep when thermodynamic information may not be current.