Coverage for nodimo / dimension.py: 100%

1# ┓• Licensed under the MIT License 

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

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

4 

5""" 

6Product 

7======= 

8 

9This module contains the class to create a quantity dimension. 

10 

11Classes 

12------- 

13Dimension 

14 Creates the dimension of a quantity. 

15""" 

16 

17from sympy import sstr, srepr, latex, Symbol, Mul, Number, S 6 ctx1abcdef

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

19from typing import Union 6 ctx1abcdef

20 

21from nodimo._internal import _sympify_number, _unsympify_number 6 ctx1abcdef

22 

23 

24class Dimension(dict): 6 ctx1abcdef

25 """The dimension of a quantity. 

26 

27 This class inherits from dictionary and adds to it representation 

28 methods to display the dimension of a quantity in the way that is 

29 conventionally done by the literature and by the ISO 80000-1. 

30 

31 Parameters 

32 ---------- 

33 **dimensions : Number 

34 Base dimensions and exponents given as keyword arguments. 

35 """ 

36 

37 def __init__(self, **dimensions: Number): 6 ctx1abcdef

38 self._dimensions: dict[str, Number] 6 ctx1abcdef

39 self._is_dimensionless: bool 6 ctx1abcdef

40 self._symbolic: Mul 6 ctx1abcdef

41 self._set_dimensions(**dimensions) 6 ctx1abcdef

42 super().__init__(**self._dimensions) 6 ctx1abcdef

43 self._set_symbolic_dimension() 6 ctx1abcdef

44 

45 def _set_dimensions(self, **dimensions: Number): 6 ctx1abcdef

46 """Sympifies and clear null dimensional exponents.""" 

47 

48 dimensions_sp = {} 6 ctx1abcdef

49 for dim, exp in dimensions.items(): 6 ctx1abcdef

50 exp_sp = _sympify_number(exp) 6 ctx1abcdef

51 if exp_sp != 0: 6 ctx1abcdef

52 dimensions_sp[dim] = exp_sp 6 ctx1abcdef

53 

54 self._dimensions = dimensions_sp 6 ctx1abcdef

55 self._is_dimensionless = all(dim == 0 for dim in dimensions_sp.values()) 6 ctx1abcdef

56 

57 def _set_symbolic_dimension(self): 6 ctx1abcdef

58 if self._is_dimensionless: 6 ctx1abcdef

59 self._symbolic = S.One 6 ctx1abcdef

60 else: 

61 factors = [] 6 ctx1abcdef

62 for dim, exp in self.items(): 6 ctx1abcdef

63 dim_symbol = Symbol(dim, commutative=False) 6 ctx1abcdef

64 factors.append(dim_symbol**exp) 6 ctx1abcdef

65 self._symbolic = Mul(*factors, evaluate=False) 6 ctx1abcdef

66 

67 def _copy(self): 6 ctx1abcdef

68 return eval(srepr(self)) 6 ctx1abcdef

69 

70 def __mul__(self, other): 6 ctx1abcdef

71 if not isinstance(other, Dimension): 6 ctx1abcdef

72 raise NotImplementedError(f"{self} and {other} cannot be multiplied") 6 ctx1abcdef

73 

74 dimensions = self._dimensions.copy() 6 ctx1abcdef

75 for dim, exp in other.items(): 6 ctx1abcdef

76 if dim in dimensions: 6 ctx1abcdef

77 dimensions[dim] += exp 6 ctx1abcdef

78 else: 

79 dimensions[dim] = exp 6 ctx1abcdef

80 

81 return Dimension(**dimensions) 6 ctx1abcdef

82 

83 def __pow__(self, exponent: Number): 6 ctx1abcdef

84 exponent_sp = _sympify_number(exponent) 6 ctx1abcdef

85 dimensions = {} 6 ctx1abcdef

86 for dim, exp in self.items(): 6 ctx1abcdef

87 dimensions[dim] = exp * exponent_sp 6 ctx1abcdef

88 

89 return Dimension(**dimensions) 6 ctx1abcdef

90 

91 def __truediv__(self, other): 6 ctx1abcdef

92 if not isinstance(other, Dimension): 6 ctx1abcdef

93 raise NotImplementedError(f"{other} cannot divide {self}") 6 ctx1abcdef

94 

95 return self * other**-1 6 ctx1abcdef

96 

97 def __str__(self) -> str: 6 ctx1abcdef

98 return sstr(self) 6 ctx1abcdef

99 

100 __repr__ = __str__ 6 ctx1abcdef

101 

102 def _repr_latex_(self): 6 ctx1abcdef

103 """Latex representation according to IPython/Jupyter.""" 

104 

105 return f'$\\displaystyle {latex(self)}$' 6 ctx1abcdef

106 

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

108 """Developer string representation according to Sympy.""" 

109 

110 class_name = type(self).__name__ 6 ctx1abcdef

111 dimensions = '' 6 ctx1abcdef

112 if not self._is_dimensionless: 6 ctx1abcdef

113 dim_exp = [] 6 ctx1abcdef

114 for dim, exp in self.items(): 6 ctx1abcdef

115 exp_ = _unsympify_number(exp) 6 ctx1abcdef

116 dim_exp.append(f'{dim}={repr(exp_)}') 6 ctx1abcdef

117 dimensions = ', '.join(dim_exp) 6 ctx1abcdef

118 

119 return f'{class_name}({dimensions})' 6 ctx1abcdef

120 

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

122 """User string representation according to Sympy.""" 

123 

124 if self._is_dimensionless: 6 ctx1abcdef

125 return printer._print(self._symbolic) 6 ctx1abcdef

126 

127 printer._settings['root_notation'] = True 6 ctx1abcdef

128 exponents = [] 6 ctx1abcdef

129 for expt in self._dimensions.values(): 6 ctx1abcdef

130 if expt < 0 or expt.is_Mul: 6 ctx1abcdef

131 exponent = f'({printer._print(expt)})' 6 ctx1abcdef

132 elif expt.is_Rational and not expt.is_Integer: 6 ctx1abcdef

133 exponent = f'({printer._print(expt)})' 6 ctx1abcdef

134 else: 

135 exponent = printer._print(expt) 6 ctx1abcdef

136 exponents.append(exponent) 6 ctx1abcdef

137 

138 printer._settings['root_notation'] = False 6 ctx1abcdef

139 dimensions = [] 6 ctx1abcdef

140 for dim, exp in zip(self._dimensions, exponents): 6 ctx1abcdef

141 if self._dimensions[dim] != 1: 6 ctx1abcdef

142 dimensions.append(f'{printer._print(dim)}**{exp}') 6 ctx1abcdef

143 else: 

144 dimensions.append(printer._print(dim)) 6 ctx1abcdef

145 

146 return '*'.join(dimensions) 6 ctx1abcdef

147 

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

149 """User string representation according to Sympy. 

150 

151 The dimension's symbol use the Sans Serif font to follow the 

152 conventional dimension representation. 

153 """ 

154 

155 if self._is_dimensionless: 6 ctx1abcdef

156 return f'\\mathsf{{{printer._print(self._symbolic)}}}' 6 ctx1abcdef

157 

158 printer._settings['root_notation'] = True 6 ctx1abcdef

159 exponents = [] 6 ctx1abcdef

160 for exp in self._dimensions.values(): 6 ctx1abcdef

161 exponents.append(printer._print(exp)) 6 ctx1abcdef

162 

163 printer._settings['root_notation'] = False 6 ctx1abcdef

164 dimensions = [] 6 ctx1abcdef

165 for dim, exp in zip(self._dimensions, exponents): 6 ctx1abcdef

166 if self._dimensions[dim] != 1: 6 ctx1abcdef

167 dimensions.append(f'\\mathsf{{{dim}}}^{{{exp}}}') 6 ctx1abcdef

168 else: 

169 dimensions.append(f'\\mathsf{{{dim}}}') 6 ctx1abcdef

170 

171 return ' '.join(dimensions) 6 ctx1abcdef

172 

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

174 """Pretty representation according to Sympy.""" 

175 

176 if self._is_dimensionless: 6 ctx1abcdef

177 return printer._print(self._symbolic) 6 ctx1abcdef

178 

179 printer._settings['root_notation'] = True 6 ctx1abcdef

180 exponents = [] 6 ctx1abcdef

181 for exp in self._dimensions.values(): 6 ctx1abcdef

182 exponents.append(printer._print(exp)) 6 ctx1abcdef

183 

184 printer._settings['root_notation'] = False 6 ctx1abcdef

185 for i, (dim, exp) in enumerate(zip(self._dimensions, exponents)): 6 ctx1abcdef

186 dimexp = printer._print(dim) 6 ctx1abcdef

187 if self._dimensions[dim] != 1: 6 ctx1abcdef

188 dimexp = dimexp**exp 6 ctx1abcdef

189 if i == 0: 6 ctx1abcdef

190 dimension = dimexp 6 ctx1abcdef

191 else: 

192 dimension *= dimexp 6 ctx1abcdef

193 

194 return dimension 6 ctx1abcdef