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fix_modify command

Syntax:

fix_modify fix-ID keyword value ... 

Examples:

fix_modify 3 temp myTemp press myPress
fix_modify 1 thermo yes 

Description:

Modify one or more parameters of a previously defined fix. Not all fix styles support all parameters.

The temp keyword is used to determine how a fix computes temperature. The specified compute ID must have been previously defined by the user via the compute command and it must be a style of compute that calculates a temperature. All fixes that compute temperatures defined their own compute by default, as described in their documentation. Thus this option allows the user to override the default method for computing T.

The press keyword is used to determine how a fix computes pressure. The specified compute ID must have been previously defined by the user via the compute command and it must be a style of compute that calculates a pressure. All fixes that compute pressures defined their own compute by default, as described in their documentation. Thus this option allows the user to override the default method for computing P.

For fixes that calculates a contribution to the potential energy of the system, the thermo keyword will include that contribution in thermodyanmic output of the potential energy, as invoked by the thermo_style command. The value of the contribution can also be printed by itself using the thermo_style custom keywords. The documentation for individual fix commands specifies whether they make a contribution to the potential energy.

Restrictions: none

Related commands:

fix, temperature, thermo_style

Default:

The option defaults are temp = ID defined by fix, press = ID defined by fix, thermo = no.