PyMOL Wiki - User contributions [en]

Center of mass

2007-04-20T17:47:46Z

Henschel:

Here is a script that calculates the center of mass from a selection.
It gets hold of the coordinates with cmd.get_model.
Make sure the atoms in the selection are of equal weight.

For a sample application, see: [http://yggdrasil.biotec.tu-dresden.de/abac/b.47.1.2___b.16.1.1___g.4.1.1.html "Convergent Evolution Examples"]

<source lang="python">
## Author: Andreas Henschel 2006

from pymol import cmd
from pymol.cgo import *

def centerOfMass(selection):
## assumes equal weights (best called with "and name ca" suffix)
model = cmd.get_model(selection)
x,y,z=0,0,0
for a in model.atom:
x+= a.coord[0]
y+= a.coord[1]
z+= a.coord[2]
return (x/len(model.atom), y/len(model.atom), z/len(model.atom))

cmd.load("/group/bioinf/Data/PDBLinks/1c7c.pdb")
cmd.select("domain", "/1c7c//A/143-283/ and name ca") ## selecting a domain

domainCenter=centerOfMass("domain")

print "Center of mass: (%.1f,%.1f,%.1f)"% domainCenter
cmd.as("cartoon", "all")
cmd.show("spheres", "domain")

## Creating a sphere CGO
com = [COLOR, 1.0, 1.0, 1.0, SPHERE]+list(domainCenter) + [3.0] ## white sphere with 3A radius
cmd.load_cgo(com, "CoM")

cmd.zoom("1c7c", 1.0)
cmd.center("domain")

#ah@bioinfws19:~/Projects/PyMOL$ pymol -qc centerOfMass4.py
#Center of mass: (-1.0,24.5,48.2)
#ah@bioinfws19:~/Projects/PyMOL$
</source>

Category:Script Library

2007-04-20T17:42:28Z

Henschel:

* [[Zero_residues]] -- Renumber residues such that the first residue is 0. Useful for alignments.

* [[Cealign]] -- Implementation of the CE Structure Alignment algorithm as a PyMOL plugin.

* [[WriteSS]] -- Writes secondary structural elements, for each residues, to a file.

* [[Process_All_Files_In_Directory]] -- Do something to all files in a directory. The examples show how to print the disulfide bond lengths, then in general all sulfur distances (not necessarily bound).

* [[Kabsch]] -- Kabsch alignment of two sets of vectors. (Part 2 of a protein alignment.)

* [[Transform_odb]] -- Transform a selection of an existing object and output as a new object. The transformation matrix is read from an "O"-style tranformation matrix file (.odb) written by "O" or by any of the Uppsala Software Factory programs (from Gerard Klegweit) such as LSQMAN.

* [[Stereo_Ray]] -- This script will create two resolution specific ray traced images rotated appropriately for inclusion into a single file to represent a stereo view of the desired macromolecule.

* [[Translate_And_Measure]] -- prints '''overlap''' if any of the atoms in molA or molB were within 4 Angstrom after translating by 1 along X

* [[Show aromatics]] -- This script will display a backbone "worm" for your protein, with all of the sidechains for aromatic residues displayed as green "sticks". Usage: Save this as "show_aromatics.pml", load your protein in PyMOL, and run the script (select "Run" from the "File" menu). (PyMOL script; TStout)

* [[Show hydrophobics]] -- This script will display a backbone "worm" for your protein, with all of the sidechains for hydrophobic residues displayed as orange "sticks". Usage: Same as "show aromatics". (PyMOL script; TStout)

* [[Show charged]] -- This script will display a backbone "worm" for your protein, with all of the sidechains for charged residues displayed as red (negative) or blue (posititve) "sticks". Usage: Same as "show aromatics". (PyMOL script; TStout)

* [[Show hydrophilic]] -- This script will display a backbone "worm" for your protein, with all of the sidechains for hydrophilic residues displayed as green "sticks". Usage: Same as "show aromatics". (PyMOL script; TStout)

* [[Show NMR constrains]] -- This script will display the NMR constrains used for a structure calculation atop a structure. Usage: Save this as "NMRcnstr.py" load your protein in PyMOL, and run the script. type upl('fname') or cns('fname') where fname is the filename with the NMR constrains you want to display.

* [[Perp Maker]] -- Creates a perpendicular plane through the center of your protein with respect to the camera's current position. (If you translate the protein towards the camera a bit, you get a nice surface, sometimes.) A stupid little script I wrote in response to a request a few months ago (and it doesn't even conform to the request!) Load a protein, run the script (read the documentation in the script). (Jason Vertrees/[[User:Tree|Tree]])

* [[PythonTerminal]] -- Allows execution of python commands from the PyMOL command line.

* [[Axes]] -- Creates a 3D-CGO object that shows the three coordinate axes.

* [[CGO Text]] -- Creates a 3D-CGO text object.

* [[List Selection]] -- Prints a list of all residues in a selection (both Python and .pml).

* [[List Colors]] -- Lists the color of all residues in a selection (both Python and .pml).

* [[List Secondary Structures]] -- Secondary structures (both predefined and those calculated with the 'dss' command) can be exported as a long string ('HHHHLLLLSSS').

* [[Split Movement]] -- Moves two parts of one object into different directions.

* [[Selection Exists]] -- Python method that returns true if a selection of a given name exists.

* [[Get Coordinates I]] -- Retrieves atom coordinates as Python objects.

* [[Get Coordinates II]] -- Retrieves atom coordinates as Python array (list object).

* [[grepset]] -- List all settings matching a given keyword. - ''by EHP''

* [[apropos]] -- List all commands matching a given keyword or whose docs contain the keyword. - ''by EHP''

* [[mouse_modes]] -- customize the default mouse bindings for Viewing or Editing modes. - ''by EHP''

* [[Measure Distance]] -- Measures the distance between two atoms (Python script).

* [[Read PDB-String]] -- Parses a string in PDB format to a PyMOL object.

* [[Color Objects]] -- Colors all objects differently (Python script).

* [[Key Wait]] -- Process key events in a Python script.

* [[Bounding Box]] -- Create a bounding box around a selection (Python script; requires numarray and Scientific; gilleain)

* [[Ellipsoid]] -- Create callback object (opengl) ellipsoids. (Python script; gilleain)

* [[pdbsurvey]] -- Surveys the pdb for recently added structures that are relevant to a user-specified keywords list (in a text file)

* [[resicolor]] -- Colors proteins according to residue type.

* [[TransformSelectionByCameraView]] -- Transforms the selection by the camera view.

* [[WFMesh]] -- Imports wavefront object mesh files; Starwars as an example!

* [[grepsel]] -- Make named selections using regular expressions (protein sequence).

* [[PowerMate Dial OS X]] -- Script and instructions to use the PowerMate dial on Mac OS X.

* [[Plane Wizard]] -- Wizard to draw planes between three picked points.

* [[Slerpy]] -- Pymol command extensions for key frame animation movie making.

* [[Helicity_check]] -- helicity_check show the evolution of O - N distances over an amino acid sequence

* [[Center Of Mass]] -- Given a selection of atoms (of equal weight) - Calculates the center of mass and represents it with a CGO sphere

[[Category:Scripting|Script Library]]

Category:Script Library

2007-04-20T17:41:08Z

Henschel:

* [[Zero_residues]] -- Renumber residues such that the first residue is 0. Useful for alignments.

* [[Cealign]] -- Implementation of the CE Structure Alignment algorithm as a PyMOL plugin.

* [[WriteSS]] -- Writes secondary structural elements, for each residues, to a file.

* [[Process_All_Files_In_Directory]] -- Do something to all files in a directory. The examples show how to print the disulfide bond lengths, then in general all sulfur distances (not necessarily bound).

* [[Kabsch]] -- Kabsch alignment of two sets of vectors. (Part 2 of a protein alignment.)

* [[Transform_odb]] -- Transform a selection of an existing object and output as a new object. The transformation matrix is read from an "O"-style tranformation matrix file (.odb) written by "O" or by any of the Uppsala Software Factory programs (from Gerard Klegweit) such as LSQMAN.

* [[Stereo_Ray]] -- This script will create two resolution specific ray traced images rotated appropriately for inclusion into a single file to represent a stereo view of the desired macromolecule.

* [[Translate_And_Measure]] -- prints '''overlap''' if any of the atoms in molA or molB were within 4 Angstrom after translating by 1 along X

* [[Show aromatics]] -- This script will display a backbone "worm" for your protein, with all of the sidechains for aromatic residues displayed as green "sticks". Usage: Save this as "show_aromatics.pml", load your protein in PyMOL, and run the script (select "Run" from the "File" menu). (PyMOL script; TStout)

* [[Show hydrophobics]] -- This script will display a backbone "worm" for your protein, with all of the sidechains for hydrophobic residues displayed as orange "sticks". Usage: Same as "show aromatics". (PyMOL script; TStout)

* [[Show charged]] -- This script will display a backbone "worm" for your protein, with all of the sidechains for charged residues displayed as red (negative) or blue (posititve) "sticks". Usage: Same as "show aromatics". (PyMOL script; TStout)

* [[Show hydrophilic]] -- This script will display a backbone "worm" for your protein, with all of the sidechains for hydrophilic residues displayed as green "sticks". Usage: Same as "show aromatics". (PyMOL script; TStout)

* [[Show NMR constrains]] -- This script will display the NMR constrains used for a structure calculation atop a structure. Usage: Save this as "NMRcnstr.py" load your protein in PyMOL, and run the script. type upl('fname') or cns('fname') where fname is the filename with the NMR constrains you want to display.

* [[Perp Maker]] -- Creates a perpendicular plane through the center of your protein with respect to the camera's current position. (If you translate the protein towards the camera a bit, you get a nice surface, sometimes.) A stupid little script I wrote in response to a request a few months ago (and it doesn't even conform to the request!) Load a protein, run the script (read the documentation in the script). (Jason Vertrees/[[User:Tree|Tree]])

* [[PythonTerminal]] -- Allows execution of python commands from the PyMOL command line.

* [[Axes]] -- Creates a 3D-CGO object that shows the three coordinate axes.

* [[CGO Text]] -- Creates a 3D-CGO text object.

* [[List Selection]] -- Prints a list of all residues in a selection (both Python and .pml).

* [[List Colors]] -- Lists the color of all residues in a selection (both Python and .pml).

* [[List Secondary Structures]] -- Secondary structures (both predefined and those calculated with the 'dss' command) can be exported as a long string ('HHHHLLLLSSS').

* [[Split Movement]] -- Moves two parts of one object into different directions.

* [[Selection Exists]] -- Python method that returns true if a selection of a given name exists.

* [[Get Coordinates I]] -- Retrieves atom coordinates as Python objects.

* [[Get Coordinates II]] -- Retrieves atom coordinates as Python array (list object).

* [[grepset]] -- List all settings matching a given keyword. - ''by EHP''

* [[apropos]] -- List all commands matching a given keyword or whose docs contain the keyword. - ''by EHP''

* [[mouse_modes]] -- customize the default mouse bindings for Viewing or Editing modes. - ''by EHP''

* [[Measure Distance]] -- Measures the distance between two atoms (Python script).

* [[Read PDB-String]] -- Parses a string in PDB format to a PyMOL object.

* [[Color Objects]] -- Colors all objects differently (Python script).

* [[Key Wait]] -- Process key events in a Python script.

* [[Bounding Box]] -- Create a bounding box around a selection (Python script; requires numarray and Scientific; gilleain)

* [[Ellipsoid]] -- Create callback object (opengl) ellipsoids. (Python script; gilleain)

* [[pdbsurvey]] -- Surveys the pdb for recently added structures that are relevant to a user-specified keywords list (in a text file)

* [[resicolor]] -- Colors proteins according to residue type.

* [[TransformSelectionByCameraView]] -- Transforms the selection by the camera view.

* [[WFMesh]] -- Imports wavefront object mesh files; Starwars as an example!

* [[grepsel]] -- Make named selections using regular expressions (protein sequence).

* [[PowerMate Dial OS X]] -- Script and instructions to use the PowerMate dial on Mac OS X.

* [[Plane Wizard]] -- Wizard to draw planes between three picked points.

* [[Slerpy]] -- Pymol command extensions for key frame animation movie making.

* [[Helicity_check]] -- helicity_check show the evolution of O - N distances over an amino acid sequence

* [[Center of mass]] -- Given a selection of atoms (of equal weight) - Calculates the center of mass and represents it with a CGO sphere

[[Category:Scripting|Script Library]]

Center of mass

2007-04-20T17:39:14Z

Henschel:

Here is a script that calculates the center of mass from a selection. It gets hold of the coordinates with cmd.get_model.
Make sure the atoms in the selection are of equal weight.

<source lang="python">
from pymol import cmd
from pymol.cgo import *

def centerOfMass(selection):
## assumes equal weights (best called with "and name ca" suffix)
model = cmd.get_model(selection)
x,y,z=0,0,0
for a in model.atom:
x+= a.coord[0]
y+= a.coord[1]
z+= a.coord[2]
return (x/len(model.atom), y/len(model.atom), z/len(model.atom))

cmd.load("/group/bioinf/Data/PDBLinks/1c7c.pdb")
cmd.select("domain", "/1c7c//A/143-283/ and name ca") ## selecting a domain

domainCenter=centerOfMass("domain")

print "Center of mass: (%.1f,%.1f,%.1f)"% domainCenter
cmd.as("cartoon", "all")
cmd.show("spheres", "domain")

## Creating a sphere CGO
com = [COLOR, 1.0, 1.0, 1.0, SPHERE]+list(domainCenter) + [3.0] ## white sphere with 3A radius
cmd.load_cgo(com, "CoM")

cmd.zoom("1c7c", 1.0)
cmd.center("domain")

#ah@bioinfws19:~/Projects/PyMOL$ pymol -qc centerOfMass4.py
#Center of mass: (-1.0,24.5,48.2)
#ah@bioinfws19:~/Projects/PyMOL$
</source>

Center of mass

2007-04-20T17:36:45Z

Henschel: New page: <source lang="python"> from pymol import cmd from pymol.cgo import * def centerOfMass(selection): ## assumes equal weights (best called with "and name ca" suffix) model = cmd.get_model(selection...

<source lang="python">

from pymol import cmd
from pymol.cgo import *

def centerOfMass(selection):
## assumes equal weights (best called with "and name ca" suffix)
model = cmd.get_model(selection)
x,y,z=0,0,0
for a in model.atom:
x+= a.coord[0]
y+= a.coord[1]
z+= a.coord[2]
return (x/len(model.atom), y/len(model.atom), z/len(model.atom))

cmd.load("/group/bioinf/Data/PDBLinks/1c7c.pdb")
cmd.select("domain", "/1c7c//A/143-283/ and name ca") ## selecting a domain

domainCenter=centerOfMass("domain")

print "Center of mass: (%.1f,%.1f,%.1f)"% domainCenter
cmd.as("cartoon", "all")
cmd.show("spheres", "domain")

## Creating a sphere CGO
com = [COLOR, 1.0, 1.0, 1.0, SPHERE]+list(domainCenter) + [3.0] ## white sphere with 3A radius
cmd.load_cgo(com, "CoM")

cmd.zoom("1c7c", 1.0)
cmd.center("domain")

#ah@bioinfws19:~/Projects/PyMOL$ pymol -qc centerOfMass4.py
#Center of mass: (-1.0,24.5,48.2)
#ah@bioinfws19:~/Projects/PyMOL$
</source>

Talk:Distance

2005-08-25T09:47:39Z

Henschel:

== Concerning modes ==

As far as I figured out,
'''mode 0''' calculates distances regardless of atom type, while
'''mode 2''' calculates distances for polar atoms.
Right? Andreas (ah at biotec.tu-dresden.de)

Talk:Distance

2005-08-25T09:46:47Z

Henschel:

== Concerning modes ==

As far as I figured out,
'''mode 0''' calculates distances regardless of atom type, while
'''mode 2''' calculates distances for polar atoms.
Right?

Distance

2005-03-11T22:09:07Z

Henschel: /* USAGE */

===DESCRIPTION===
"distance" creates a new distance object between two
selections. It will display all distances within the cutoff.

===USAGE===
distance
distance (selection1), (selection2)
distance name = (selection1), (selection2) [,cutoff [,mode] ]

name = name of distance object
selection1, selection2 = atom selections
cutoff = maximum distance to display
mode = 0 (default)

===PYMOL API===
cmd.distance( string name, string selection1, string selection2,
string cutoff, string mode )
# returns the average distance between all atoms/frames

===NOTES===
The distance wizard makes measuring distances easier than using
the "dist" command for real-time operations.

"dist" alone will show distances between selections (pk1) and (pk1),
which can be set using the PkAt mouse action (usually CTRL-middle-click).

[[Category:Commands|distance]]