39 lines
860 B
Python
39 lines
860 B
Python
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"""Trait for implementing domain elements. """
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from sympy.utilities import public
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@public
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class DomainElement:
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"""
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Represents an element of a domain.
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Mix in this trait into a class whose instances should be recognized as
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elements of a domain. Method ``parent()`` gives that domain.
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"""
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__slots__ = ()
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def parent(self):
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"""Get the domain associated with ``self``
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Examples
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========
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>>> from sympy import ZZ, symbols
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>>> x, y = symbols('x, y')
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>>> K = ZZ[x,y]
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>>> p = K(x)**2 + K(y)**2
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>>> p
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x**2 + y**2
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>>> p.parent()
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ZZ[x,y]
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Notes
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=====
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This is used by :py:meth:`~.Domain.convert` to identify the domain
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associated with a domain element.
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"""
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raise NotImplementedError("abstract method")
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