Transport modules#

Velocity#

Description#

Analyse mean velocity..

Reads in coordinates and velocities from a trajectory and calculates a velocity profile along a given axis. The obtained profile is averaged over the 4 symmetric slab halfs.Error bars are estimated via block averaging as described in [1].

[1] Hess, B. Determining the shear viscosity of model liquids from molecular

dynamics simulations. The Journal of Chemical Physics 116, 209-217 (2002).

Parameters#

atomgroupAtomGroup

Atomgroup on which the analysis is executed

dimint

Dimension for position binning (x=0, y=1, z=2)

vdimint

Dimension for velocity binning (x=0, y=1, z=2)

n_binsint

Number of bins. For making use of symmetry must be a multiple of 4.

n_blockint

Maximum number of blocks for block averaging error estimate; 1 results in standard error

make_wholebool

Make molecules whole; If the input already contains whole molecules this can be disabled to gain speedup

output_suffixstr

Suffix for output filenames

concfreqint

Default number of frames after which results are calculated and files refreshed. If 0 results are only calculated at the end of the analysis and not saved by default.

verbosebool

Turn on more logging and debugging

Attributes#

results.znp.ndarray

bins [nm]

results.vnp.ndarray

velocity profile [m/s]

results.eesnp.ndarray

velocity error estimate [m/s]

results.symznp.ndarray

symmetrized bins [nm]

results.symvelnp.ndarray

symmetrized velocity profile [m/s]

results.symeesnp.ndarray

symmetrized velocity error estimate [m/s]