Coverage for /usr/lib/python3/dist-packages/sympy/core/_print_helpers.py: 71%

1""" 

2Base class to provide str and repr hooks that `init_printing` can overwrite. 

3 

4This is exposed publicly in the `printing.defaults` module, 

5but cannot be defined there without causing circular imports. 

6""" 

7 

8class Printable: 

9 """ 

10 The default implementation of printing for SymPy classes. 

11 

12 This implements a hack that allows us to print elements of built-in 

13 Python containers in a readable way. Natively Python uses ``repr()`` 

14 even if ``str()`` was explicitly requested. Mix in this trait into 

15 a class to get proper default printing. 

16 

17 This also adds support for LaTeX printing in jupyter notebooks. 

18 """ 

19 

20 # Since this class is used as a mixin we set empty slots. That means that 

21 # instances of any subclasses that use slots will not need to have a 

22 # __dict__. 

23 __slots__ = () 

24 

25 # Note, we always use the default ordering (lex) in __str__ and __repr__, 

26 # regardless of the global setting. See issue 5487. 

27 def __str__(self): 

28 from sympy.printing.str import sstr 

29 return sstr(self, order=None) 

30 

31 __repr__ = __str__ 

32 

33 def _repr_disabled(self): 

34 """ 

35 No-op repr function used to disable jupyter display hooks. 

36 

37 When :func:`sympy.init_printing` is used to disable certain display 

38 formats, this function is copied into the appropriate ``_repr_*_`` 

39 attributes. 

40 

41 While we could just set the attributes to `None``, doing it this way 

42 allows derived classes to call `super()`. 

43 """ 

44 return None 

45 

46 # We don't implement _repr_png_ here because it would add a large amount of 

47 # data to any notebook containing SymPy expressions, without adding 

48 # anything useful to the notebook. It can still enabled manually, e.g., 

49 # for the qtconsole, with init_printing(). 

50 _repr_png_ = _repr_disabled 

51 

52 _repr_svg_ = _repr_disabled 

53 

54 def _repr_latex_(self): 

55 """ 

56 IPython/Jupyter LaTeX printing 

57 

58 To change the behavior of this (e.g., pass in some settings to LaTeX), 

59 use init_printing(). init_printing() will also enable LaTeX printing 

60 for built in numeric types like ints and container types that contain 

61 SymPy objects, like lists and dictionaries of expressions. 

62 """ 

63 from sympy.printing.latex import latex 

64 s = latex(self, mode='plain') 

65 return "$\\displaystyle %s$" % s