diffcalc.hkl.calc

Routines for calculating miller indices and diffractometer positions.

Module implementing calculations based on UB matrix data and diffractometer constraints.

Classes

HklCalculation(ubcalc, constraints)

Class for converting between miller indices and diffractometer position.

class diffcalc.hkl.calc.HklCalculation(ubcalc, constraints)

Class for converting between miller indices and diffractometer position.

ubcalc

Reference to UBcalculation object containing UB matrix data.

Type

UBcalculation

constraints

Reference to Constraints object containing diffractometer constraint settings.

get_hkl(pos: Position, wavelength: float) → Tuple[float, float, float]

Calculate miller indices corresponding to a diffractometer positions.

get_virtual_angles(pos: Position, asdegrees: bool = True) → Dict[str, float]

Calculate pseudo-angles corresponding to a diffractometer position.

Attributes

asdict

Serialise the object into a JSON compatible dictionary.

Methods

fromdict(data)	Construct HklCalculation instance from a JSON compatible dictionary.
get_hkl(pos, wavelength)	Calculate miller indices corresponding to a diffractometer positions.
get_position(h, k, l, wavelength[, asdegrees])	Calculate diffractometer position from miller indices and wavelength.
get_virtual_angles(pos[, asdegrees])	Calculate pseudo-angles corresponding to a diffractometer position.

get_hkl(pos: Position, wavelength: float) → Tuple[float, float, float]

Calculate miller indices corresponding to a diffractometer positions.

Parameters

pos (Position) – Diffractometer position.

Returns

Miller indices corresponding to the specified diffractometer position at the given wavelength.

Return type

Tuple[float, float, float]

get_virtual_angles(pos: Position, asdegrees: bool = True) → Dict[str, float]

Calculate pseudo-angles corresponding to a diffractometer position.

Parameters

• pos (Position) – Diffractometer position.

• asdegrees (bool = True) – If True, return angles in degrees.

Returns

Returns alpha, beta, betain, betaout, naz, psi, qaz, tau, theta and ttheta angles.

Return type

Dict[str, float]

get_position(h: float, k: float, l: float, wavelength: float, asdegrees: bool = True) → List[Tuple[Position, Dict[str, float]]]

Calculate diffractometer position from miller indices and wavelength.

The calculated positions and angles are verified by checking that they map to the requested miller indices.

Parameters

• h (float) – h miller index.

• k (float) – k miller index.

• l (float) – l miller index.

• wavelength (float) – wavelength in Angstroms.

• asdegrees (bool) – If True, return angles in degrees.

Returns

List of all solutions matching the input miller indices that consists of pairs of diffractometer position object and virtual angles dictionary.

Return type

List[Tuple[Position, Dict[str, float]]]

property asdict: Dict[str, Any]

Serialise the object into a JSON compatible dictionary.

Returns

Dictionary containing properties of hkl class. Can be unpacked to recreate HklCalculation object using fromdict class method below.

Return type

Dict[str, Any]

classmethod fromdict(data: Dict[str, Any]) → HklCalculation

Construct HklCalculation instance from a JSON compatible dictionary.

Parameters

data (Dict[str, Any]) – Dictionary containing properties of hkl class, must have the equivalent structure of asdict method above.

Returns

Instance of this class created from the dictionary.

Return type

HklCalculation