GSAS-style Dampening Factors

Dampening factor for any refined value (lattice parameters, atomic positions etc.), for those who like to think that they know better than the least squares algorithm.

''Rather than the true GSAS dampening [applied shift = (10-damp)/10], an exponential function is used, scaled to useful dampening values of 0-9
''Useful dampening factors range from values of 0 (no dampening) to 9 (1% applied shift)
''List of DampFactor,AppliedChanges: 0,1; 1,0.607; 2,0.368; 3,0.223; 4,0.135; 5,0.082; 6,0.50; 7,0.030; 8,0.018; 9,0.011
''e.g. A simple lattice parameter refinement with dampening factors of 9, 8, 7, 6, 5, 4, 3, 2, 1 and 0
''     converges in 422, 271, 173, 111, 71, 45, 28, 17, 10 and 5 cycles, respectively
''Example of use: 
'' site O1	x @  0.30696 Damp(3)	y 0	z 0.25	occ O-2	1	beq @ 2 Damp(7)
 
macro Damp(DampFactor) 
{
   update = Val + (Change*(1/Exp(DampFactor/2))); 
}

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