Coverage for gpaw/kpoint.py: 97%

1# Copyright (C) 2003 CAMP 

2# Please see the accompanying LICENSE file for further information. 

3 

4"""This module defines a ``KPoint`` class.""" 

5from typing import Optional 

6from gpaw.projections import Projections 

7 

8 

9class KPoint: 

10 """Class for a single k-point. 

11 

12 The KPoint class takes care of all wave functions for a 

13 certain k-point and a certain spin. 

14 

15 Attributes: 

16 

17 eps_n: float ndarray 

18 Eigenvalues. 

19 f_n: float ndarray 

20 Occupation numbers. The occupation numbers already include the 

21 k-point weight in supercell calculations. 

22 """ 

23 

24 def __init__(self, 

25 weightk: float, 

26 weight: float, 

27 s: int, 

28 k: int, 

29 q: int, 

30 phase_cd=None): 

31 """Construct k-point object. 

32 

33 Parameters: 

34 

35 weightk: 

36 Weight of this k-point. 

37 weight: 

38 Old confusing weight. 

39 s: int 

40 Spin index: up or down (0 or 1). 

41 k: int 

42 k-point IBZ-index. 

43 q: int 

44 local k-point index. 

45 phase_cd: complex ndarray 

46 Bloch phase-factors for translations - axis c=0,1,2 

47 and direction d=0,1. 

48 """ 

49 

50 self.weightk = weightk # pure k-point weight 

51 self.weight = weight # old confusing weight 

52 self.s = s # spin index 

53 self.k = k # k-point index 

54 self.q = q # local k-point index 

55 self.phase_cd = phase_cd 

56 

57 self.eps_n = None 

58 self.f_n = None 

59 self._projections: Optional[Projections] = None 

60 

61 # Only one of these two will be used: 

62 self.psit = None # UniformGridMatrix/PWExpansionMatrix 

63 self.C_nM = None # LCAO coefficients for wave functions 

64 

65 # LCAO stuff: 

66 self.rho_MM = None 

67 self.S_MM = None 

68 self.T_MM = None 

69 

70 def __repr__(self): 

71 return (f'KPoint(weight={self.weight}, weightk={self.weightk}, ' 

72 f's={self.s}, k={self.k}, q={self.q})') 

73 

74 @property 

75 def projections(self) -> Projections: 

76 assert self._projections is not None 

77 return self._projections 

78 

79 @projections.setter 

80 def projections(self, value): 

81 self._projections = value 

82 

83 @property 

84 def P_ani(self): 

85 if self._projections is not None: 

86 return {a: P_ni for a, P_ni in self.projections.items()} 

87 

88 @property 

89 def psit_nG(self): 

90 if self.psit is not None: 

91 return self.psit.array