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dump_modify command

Syntax:

dump_modify dump-ID keyword value ... 

Examples:

dump_modify 1 format "%d %d %20.15g %g %g" scale yes
dump_modify myDump image yes scale no
dump_modify 1 header xyz 

Description:

Modify the parameters of a previously defined dump command. Not all parameters are relevant to all dump styles.

Each dump style has a default C-style format string which simply specifies %d for integers and %g for real values. The format keyword can be used to override the default with a new C-style format string. Do not include a trailing "\n" newline character in the format string.

The scale and image keywords apply only to dump atom commands. A scale value of yes means atom coords are written in normalized (scaled) units from 0.0 to 1.0 in each box dimension. A value of no means they are written in absolute distance units (e.g. Angstroms or sigma). If the image value is yes, 3 flags are appended to each atom's coords which are the absolute box image of the atom in each dimension. For example, an x image flag of -3 with a normalized coord of 0.5 means the atom is in the center of the box, but has passed thru the box boundary 3 times and is really 3 box lengths to the left of its current coordinate.

The header keyword determines the file format for the snapshots. A value of item means each keyword is prefaced by "ITEM:" which is compatible with previous versions of LAMMPS. A value of self is a self-documenting format where each keyword is followed by the number of rows and columns of data that follow it. This makes it easy to write post-processing codes that parse the dump output. A value of xyz writes the dump file in the XYZ format used by other molecular modeling codes. For dump atom commands, each line will have 4 quantities: the atom type and unscaled coordinates. For dump custom commands, each line will still list the quantities it specifies.

Restrictions: none

Related commands:

dump, undump

Default:

The option defaults are format = %d and %g for each integer or floating point value, scale = yes, image = no, header = item .