# compute pressure/uef command

## Syntax

``` LAMMPS
compute ID group-ID pressure/uef temp-ID keyword ...
```

-   ID, group-ID are documented in [compute](compute) command
-   pressure/uef = style name of this compute command
-   temp-ID = ID of compute that calculates temperature, can be NULL if
    not needed
-   zero or more keywords may be appended
-   keyword = *ke* or *pair* or *bond* or *angle* or *dihedral* or
    *improper* or *kspace* or *fix* or *virial*

## Examples

``` LAMMPS
compute 1 all pressure/uef my_temp_uef
compute 2 all pressure/uef my_temp_uef virial
```

## Description

This command is used to compute the pressure tensor in the reference
frame of the applied flow field when [fix nvt/uef](fix_nh_uef) or [fix
npt/uef](fix_nh_uef) is used. It is not necessary to use this command to
compute the scalar value of the pressure. A [compute
pressure](compute_pressure) may be used for that purpose.

The keywords and output information are documented in
[compute_pressure](compute_pressure).

## Restrictions

This fix is part of the UEF package. It is only enabled if LAMMPS was
built with that package. See the [Build package](Build_package) page for
more info.

This command can only be used when [fix nvt/uef](fix_nh_uef) or [fix
npt/uef](fix_nh_uef) is active.

The kinetic contribution to the pressure tensor will be accurate only
when the compute specified by *temp-ID* is a [compute
temp/uef](compute_temp_uef).

## Related commands

[compute pressure](compute_pressure), [fix nvt/uef](fix_nh_uef),
[compute temp/uef](compute_temp_uef)

## Default

none