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## selection.randomize_xyz() -- randomize selected coordinates

`randomize_xyz(deviation)`

> This command randomizes the Cartesian coordinates of the selected atoms. If deviation is positive, the coordinates are randomized by the addition of a random number uniformly distributed in the interval from to angstroms. If deviation is negative, the coordinates are assigned a random value uniformly distributed in the interval from to angstroms.

> Any defined rigid bodies (see Section 5.3.4) remain rigid; only their mass centers are modified by this command (no rotation is done).

Example: examples/commands/randomize_xyz.py

      # Example for: selection.randomize_xyz()

      # This will randomize the X,Y,Z of the model:

      from modeller import *

      env = environ()
      env.io.atom_files_directory = '../atom_files'

      mdl = model(env, file='1fas')

      # Act on all atoms in the model
      sel = selection(mdl)

      # Change all existing X,Y,Z for +- 4 angstroms:
      sel.randomize_xyz(deviation=4.0)
      mdl.write(file='1fas.ini1')

      # Assign X,Y,Z in the range from -100 to 100 angstroms:
      sel.randomize_xyz(deviation=-100.0)
      mdl.write(file='1fas.ini2')