Coverage for nodimo / model.py: 100%

1# ┓• Licensed under the MIT License 

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

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

4 

5""" 

6Model 

7===== 

8 

9This module contains the classes to create (non)dimensional models. 

10 

11Classes 

12------- 

13Model 

14 Creates a (non)dimensional model from a given set of quantities. 

15""" 

16 

17from sympy import Number 6 ctx1abcdef

18from itertools import combinations 6 ctx1abcdef

19 

20from nodimo.quantity import Quantity 6 ctx1abcdef

21from nodimo.groups import DimensionalGroup, ScalingGroup 6 ctx1abcdef

22from nodimo.relation import Relation 6 ctx1abcdef

23from nodimo._internal import _print_horizontal_line, _unsympify_number 6 ctx1abcdef

24 

25 

26class Model(Relation): 6 ctx1abcdef

27 """(Non)dimensional model built from a given set of quantities. 

28 

29 This class builds relations from the resulting quantities of a group 

30 transformation (DimensionalGroup). Every relation is associated with 

31 a scaling group, which are built using the given scaling quantities. 

32 

33 Parameters 

34 ---------- 

35 *quantities : Quantity 

36 Quantities that constitute the model. 

37 **dimensions : int 

38 Aimed dimensions for the model given as keyword arguments. 

39 

40 Attributes 

41 ---------- 

42 quantities : list[Quantity] 

43 List with the quantities that constitute the model. 

44 relations : dict[ScalingGroup, Relation] 

45 Dictionary containing pairs of scaling groups and relations. 

46 

47 Methods 

48 ------- 

49 show(use_custom_css=True, use_unicode=True) 

50 Prints scaling groups and respective (non)dimensional relations. 

51 

52 Raises 

53 ------ 

54 ValueError 

55 If the number of scaling quantities is lower than necessary. 

56 

57 Warns 

58 ----- 

59 NodimoWarning 

60 Dimensions that are treated as independent. 

61 

62 Examples 

63 -------- 

64 * Free fall 

65 

66 Dimensions: mass ``M``, length ``L`` and time ``T``. 

67 

68 Quantities: height ``z``, mass ``m``, velocity ``v``, 

69 gravitational acceleration ``g``, time ``t``, 

70 initial height ``z0`` and initial velocity ``v0`` 

71 

72 Considering the scaling groups that can be formed with ``g``, ``z0`` 

73 and ``v0``, the ``model`` for ``z`` is built and displayed as: 

74 

75 >>> from nodimo import Quantity, Model 

76 >>> z = Quantity('z', L=1, dependent=True) 

77 >>> m = Quantity('m', M=1) 

78 >>> v = Quantity('v', L=1, T=-1) 

79 >>> g = Quantity('g', L=1, T=-2, scaling=True) 

80 >>> t = Quantity('t', T=1) 

81 >>> z0 = Quantity('z0', L=1, scaling=True) 

82 >>> v0 = Quantity('v0', L=1, T=-1, scaling=True) 

83 >>> model = Model(z, m, v, g, t, z0, v0) 

84 >>> model.show() 

85 """ 

86 

87 def __init__(self, *quantities: Quantity, **dimensions: Number): 6 ctx1abcdef

88 super().__init__(*quantities) 6 ctx1abcdef

89 self._set_dimensions(**dimensions) 6 ctx1abcdef

90 self._scaling_groups: list[ScalingGroup] 6 ctx1abcdef

91 self._relations: dict[ScalingGroup, Relation] 6 ctx1abcdef

92 self._set_model() 6 ctx1abcdef

93 

94 @property 6 ctx1abcdef

95 def relations(self) -> dict[ScalingGroup, Relation]: 6 ctx1abcdef

96 return self._relations 6 ctx1abcdef

97 

98 def _set_model(self): 6 ctx1abcdef

99 self._set_matrix_rank() 6 ctx1abcdef

100 self._set_scaling_quantities() 6 ctx1abcdef

101 self._validate_model() 6 ctx1abcdef

102 self._set_scaling_groups() 6 ctx1abcdef

103 self._set_relations() 6 ctx1abcdef

104 self._clear_null_dimensions() 6 ctx1abcdef

105 

106 def _validate_model(self): 6 ctx1abcdef

107 if len(self._scaling_quantities) < self._rank: 6 ctx1abcdef

108 raise ValueError( 6 ctx1abcdef

109 f"The model must have at least {self._rank} scaling quantities" 

110 ) 

111 

112 def _set_scaling_groups(self): 6 ctx1abcdef

113 scaling_groups = [] 6 ctx1abcdef

114 for scgroup in combinations(self._scaling_quantities, self._rank): 6 ctx1abcdef

115 try: 6 ctx1abcdef

116 scaling_groups.append(ScalingGroup(*scgroup)) 6 ctx1abcdef

117 except: 6 ctx1abcdef

118 pass 6 ctx1abcdef

119 

120 if len(scaling_groups) > 1: 6 ctx1abcdef

121 idnum = 1 6 ctx1abcdef

122 for scgroup in scaling_groups: 6 ctx1abcdef

123 scgroup._id_number = idnum 6 ctx1abcdef

124 idnum += 1 6 ctx1abcdef

125 

126 self._scaling_groups = scaling_groups 6 ctx1abcdef

127 

128 def _set_relations(self): 6 ctx1abcdef

129 relations = {} 6 ctx1abcdef

130 for scgroup in self._scaling_groups: 6 ctx1abcdef

131 quantities = list(self._nonscaling_quantities) 6 ctx1abcdef

132 for qty in self._scaling_quantities: 6 ctx1abcdef

133 if qty not in scgroup: 6 ctx1abcdef

134 reset_qty = qty._copy() 6 ctx1abcdef

135 reset_qty._is_scaling = False 6 ctx1abcdef

136 quantities.append(reset_qty) 6 ctx1abcdef

137 quantities.extend(scgroup.quantities) 6 ctx1abcdef

138 

139 dgroup = DimensionalGroup(*quantities, **self._dimensions) 6 ctx1abcdef

140 for prod in dgroup.quantities: 6 ctx1abcdef

141 if prod._is_product: 6 ctx1abcdef

142 prod._is_dependent = any(qty.is_dependent for qty in prod.factors) 6 ctx1abcdef

143 

144 if len(self._scaling_groups) == 1: 6 ctx1abcdef

145 relation_name = 'Phi' 6 ctx1abcdef

146 else: 

147 relation_name = f'Phi_{scgroup._id_number}' 6 ctx1abcdef

148 

149 relations[scgroup] = Relation(*dgroup.quantities, name=relation_name) 6 ctx1abcdef

150 

151 self._relations = relations 6 ctx1abcdef

152 

153 def show(self, use_custom_css: bool = True, use_unicode: bool = True): 6 ctx1abcdef

154 super().show(use_custom_css=use_custom_css, use_unicode=use_unicode) 6 ctx1abcdef

155 for i, (scgroup, relation) in enumerate(self._relations.items()): 6 ctx1abcdef

156 _print_horizontal_line() 6 ctx1abcdef

157 scgroup.show(use_custom_css=False, use_unicode=use_unicode) 6 ctx1abcdef

158 relation.show(use_custom_css=use_custom_css, use_unicode=use_unicode) 6 ctx1abcdef

159 

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

161 return ( 6 ctx1abcdef

162 frozenset(self._scaling_quantities), 

163 frozenset(self._nonscaling_quantities), 

164 frozenset(self._dimensions.items()), 

165 ) 

166 

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

168 class_name = type(self).__name__ 6 ctx1abcdef

169 quantities = ', '.join(printer._print(qty) for qty in self._quantities) 6 ctx1abcdef

170 

171 if self._is_dimensionless: 6 ctx1abcdef

172 dimensions = '' 6 ctx1abcdef

173 else: 

174 dims = [] 6 ctx1abcdef

175 for dim_name, dim_exp in self._dimensions.items(): 6 ctx1abcdef

176 dim_exp_ = _unsympify_number(dim_exp) 6 ctx1abcdef

177 if isinstance(dim_exp_, str): 6 ctx1abcdef

178 dim_exp_ = f"'{dim_exp_}'" 6 ctx1abcdef

179 dims.append(f'{dim_name}={dim_exp_}') 6 ctx1abcdef

180 dimensions = f", {', '.join(dims)}" 6 ctx1abcdef

181 

182 return f'{class_name}({quantities}{dimensions})' 6 ctx1abcdef