soprano.calculate.xrd.sel_rules

Providing an interface to selection rules for XRD peaks and various spacegroups.

Functions

get_sel_rule_from_hall(h)	Generate a function object that acts as a selection rule for XRD lines for the given symmetry group expressed in Hall number notation
get_sel_rule_from_international(n[, o])	Generate a function object that acts as a selection rule for XRD lines for the given symmetry group expressed in international number notation

soprano.calculate.xrd.sel_rules._evenq(x)

Returns True if x is even

soprano.calculate.xrd.sel_rules._ifq(cond, ifT, ifF)

Fortran-style ternary if

soprano.calculate.xrd.sel_rules._integerq(x)

Returns true if x is integer

soprano.calculate.xrd.sel_rules.get_sel_rule_from_hall(h)

Generate a function object that acts as a selection rule for XRD lines for the given symmetry group expressed in Hall number notation

Args:

h (int): Hall number of the required spacegroup

Returns:

rule_func (function< list<int> >

=> <bool>): a function that can be used to test triples of

Miller indices h,k,l to verify whether the

related plane gives rise or not to a peak

Raises:

RuntimeError: if the database of XRD selection rules or that of

Hall numbers was not properly loaded

ValueError: if the passed argument is invalid

soprano.calculate.xrd.sel_rules.get_sel_rule_from_international(n, o='all')

Generate a function object that acts as a selection rule for XRD lines for the given symmetry group expressed in international number notation

Args:

n (int): International number of the required spacegroup

o (Optional[int]): Sub-option of the required spacegroup

Returns:

rule_func (function< list<int> >

=> <bool>): a function that can be used to test triples of

Miller indices h,k,l to verify whether the

related plane gives rise or not to a peak

Raises:

RuntimeError: if the database of XRD selection rules was not properly

loaded

ValueError: if some of the passed arguments are invalid