psico.electrostatics

Electrostatics (simple alternative to the APBS Tools Plugin)

  1. 2012 Thomas Holder

License: BSD-2-Clause

Functions

apbs_surface([selection, maximum, minimum, ...])

Show electrostatic potential on surface (calculated with APBS).

map_new_apbs(name[, selection, grid, ...])

Create electrostatic potential map with APBS.

validate_apbs_exe(exe)

Get and validate apbs executable.

volume_esp(name, map[, stops, neg, pos, ...])

Create a volume object from a map object with default coloring for electrostatic potential (similar to positive and negative isosurface).

volume_fofc(name, map[, stops, neg, pos, ...])

Create a difference density volume object.

psico.electrostatics.apbs_surface(selection='all', maximum=None, minimum=None, map_name=None, ramp_name=None, grid=0.5, quiet=1, *, group_name=None, _self=...)[source]

Show electrostatic potential on surface (calculated with APBS).

Important: surface_color is a object property, so when calculating surface potential for different selections and visualize them all together, you should first split them into separate objects.

Usage

apbs_surface [ selection [, maximum [, minimum ]]]

Example

fetch 2x19, async=0 split_chains apbs_surface 2x19_A, 10 apbs_surface 2x19_B, 10

See Also

map_new_apbs, APBS Tools Plugin, isosurface, gradient, util.protein_vacuum_esp

psico.electrostatics.map_new_apbs(name, selection='all', grid=0.5, buffer=10.0, state=1, preserve=0, exe='', assign=-1, focus='', quiet=1, _template='', *, _self=...)[source]

Create electrostatic potential map with APBS.

For more control over parameters and a graphical user interface I recommend to use the APBS Tools Plugin instead.

In case of missing atoms or residues I recommend to remodel the input structure with modeller before calculating the electrostatic potential.

If selection has no charges and radii, they will be automatically assigned with PyMOL (not with pdb2pqr).

See Also

apbs_surface, map_new (coulomb), APBS Tools Plugin

psico.electrostatics.validate_apbs_exe(exe)[source]

Get and validate apbs executable. Raise CmdException if not found or broken.

psico.electrostatics.volume_esp(name, map, stops=(0.1, 1.0), neg='red', pos='blue', opacity=0.2, quiet=1, *, _self=...)[source]

Create a volume object from a map object with default coloring for electrostatic potential (similar to positive and negative isosurface).

Arguments

name = string: name for the new volume object

map = string: name of the map object to use

stops = list of floats: 2 or 3 values in standard deviations for creating the volume ramp {default: [0.1, 1.0]}

neg = string: color for negative volume {default: red}

pos = string: color for positive volume {default: blue}

opacity = float: maximum opacity in volume ramp {default: 0.2}

See Also

volume

psico.electrostatics.volume_fofc(name, map, stops=(2.5, 3.0, 4.0), neg='red', pos='green', opacity=0.4, quiet=1, *, _self=...)[source]

Create a difference density volume object.

See Also

volume_esp