Coverage for nodimo / relation.py: 100%

1# ┓• Licensed under the MIT License 

2# ┏┓┏┓┏┫┓┏┳┓┏┓ Copyright (c) 2024 Rodrigo Castro 

3# ┛┗┗┛┗┻┗┛┗┗┗┛ https://nodimo.readthedocs.io 

4 

5""" 

6Relation 

7======== 

8 

9This module contains the class to create a relation between quantities. 

10 

11Classes 

12------- 

13Relation 

14 Creates a relation between quantities. 

15""" 

16 

17from sympy import Symbol, Equality, Function 6 ctx1abcdef

18from sympy.printing.pretty.stringpict import prettyForm 6 ctx1abcdef

19 

20from nodimo.quantity import Quantity, Constant 6 ctx1abcdef

21from nodimo.groups import HomogeneousGroup, IndependentGroup 6 ctx1abcdef

22from nodimo._internal import _prettify_name 6 ctx1abcdef

23 

24 

25class Relation(HomogeneousGroup, IndependentGroup): 6 ctx1abcdef

26 """Creates a relation between quantities. 

27 

28 Parameters 

29 ---------- 

30 *quantities : Quantity 

31 Quantities that constitute the relation. 

32 

33 Attributes 

34 ---------- 

35 quantities : list[Quantity] 

36 Quantities that constitute the relation. 

37 

38 Raises 

39 ------ 

40 ValueError 

41 If there is more than one dependent quantity. 

42 

43 Examples 

44 -------- 

45 

46 >>> from nodimo import Quantity, Relation 

47 >>> F = Quantity('F', M=1, L=1, T=-2, dependent=True) 

48 >>> m = Quantity('m', M=1) 

49 >>> a = Quantity('a', L=1, T=-2) 

50 >>> rel = Relation(F, m, a) 

51 """ 

52 

53 def __init__(self, *quantities: Quantity, name: str = 'f'): 6 ctx1abcdef

54 super(Relation, self).__init__(*quantities) 6 ctx1abcdef

55 super(HomogeneousGroup, self).__init__(*self._quantities) 6 ctx1abcdef

56 self._name: str = name 6 ctx1abcdef

57 self._set_relation() 6 ctx1abcdef

58 

59 def _set_relation(self): 6 ctx1abcdef

60 self._set_dependent_quantities() 6 ctx1abcdef

61 self._validate_relation() 6 ctx1abcdef

62 self._set_symbolic_relation() 6 ctx1abcdef

63 

64 def _validate_relation(self): 6 ctx1abcdef

65 if len(self._dependent_quantities) > 1: 6 ctx1abcdef

66 raise ValueError("A relation cannot have more than one dependent quantity") 6 ctx1abcdef

67 elif len(self._dependent_quantities) == 0: 6 ctx1abcdef

68 self._dependent_quantities = (Constant('const'),) 6 ctx1abcdef

69 

70 def _set_symbolic_relation(self): 6 ctx1abcdef

71 dep_qty = self._dependent_quantities[0] 6 ctx1abcdef

72 indep_qts_func = Function(self._name)(*self._independent_quantities) 6 ctx1abcdef

73 self._symbolic = Equality(dep_qty, indep_qts_func, evaluate=False) 6 ctx1abcdef

74 

75 def _key(self) -> tuple: 6 ctx1abcdef

76 return ( 6 ctx1abcdef

77 tuple(self._dependent_quantities), 

78 frozenset(self._independent_quantities), 

79 ) 

80 

81 def _sympy_(self): 6 ctx1abcdef

82 return self._symbolic 6 ctx1abcdef

83 

84 def _sympyrepr(self, printer) -> str: 6 ctx1abcdef

85 class_name = type(self).__name__ 6 ctx1abcdef

86 quantities = ', '.join( 6 ctx1abcdef

87 printer._print(qty._unreduced) for qty in self._quantities 

88 ) 

89 name = f", name='{self._name}'" if self._name != 'f' else '' 6 ctx1abcdef

90 

91 return f'{class_name}({quantities}{name})' 6 ctx1abcdef

92 

93 def _sympystr(self, printer) -> str: 6 ctx1abcdef

94 name = self._name 6 ctx1abcdef

95 dep_qty = printer._print(self._dependent_quantities[0]._unreduced) 6 ctx1abcdef

96 indep_qts = ', '.join( 6 ctx1abcdef

97 printer._print(qty._unreduced) for qty in self._independent_quantities 

98 ) 

99 

100 return f'{dep_qty} = {name}({indep_qts})' 6 ctx1abcdef

101 

102 def _latex(self, printer) -> str: 6 ctx1abcdef

103 name = printer._print(Symbol(self._name)) 6 ctx1abcdef

104 dep_qty = printer._print(self._dependent_quantities[0]._unreduced) 6 ctx1abcdef

105 indep_qts = R',\ '.join( 6 ctx1abcdef

106 printer._print(qty._unreduced) for qty in self._independent_quantities 

107 ) 

108 

109 return f'{dep_qty} = {name}\\left({indep_qts}\\right)' 6 ctx1abcdef

110 

111 def _pretty(self, printer) -> prettyForm: 6 ctx1abcdef

112 name = _prettify_name(self._name) 6 ctx1abcdef

113 dep_qty = printer._print(self._dependent_quantities[0]._unreduced) 6 ctx1abcdef

114 indep_qts = prettyForm('') 6 ctx1abcdef

115 for i, qty in enumerate(self._independent_quantities): 6 ctx1abcdef

116 sep = ', ' if i > 0 else '' 6 ctx1abcdef

117 indep_qts = prettyForm( 6 ctx1abcdef

118 *indep_qts.right(sep, printer._print(qty._unreduced)) 

119 ) 

120 indep_qts = prettyForm(*indep_qts.parens()) 6 ctx1abcdef

121 

122 return prettyForm(*dep_qty.right(' = ', name, indep_qts)) 6 ctx1abcdef