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quasi_newton() -- optimize atoms with quasi-Newton minimization

edat = <energy_data>   objective function parameters
schedule_scale = <physical.values> 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 factors for physical restraint types in scaling the schedule
residue_span_range = <int:2> 0 99999 range of residues spanning the allowed distances; for MAKE_RESTRAINTS, PICK_RESTRAINTS, non-bonded dynamic pairs
max_iterations = <int:1> 200 maximal iterations in optimization
output = <str:1> 'LONG' 'NO_REPORT' | 'REPORT'
min_atom_shift = <float:1> 0.010 minimal atomic shift for the optimization convergence test
actions = []   list of periodic actions

Output:
molpdf

Requirements:
restraints

This functions in a very similar way to conjugate_gradients(), but uses a variable metric (quasi-Newton) method instead to find the minimum. The algorithm implemented in MODELLER is the BFGS or Broyden-Fletcher-Goldfarb-Shanno method [Press et al., 1992].


next up previous contents index
Next: molecular_dynamics() optimize Up: The optimizers module: optimization Previous: conjugate_gradients() optimize   Contents   Index
Ben Webb 2007-01-19