Relationships




Parents 
Quantity 
Any specification of how many or how much of something there is. Accordingly, there are two subclasses of Quantity: Number (how many) and PhysicalQuantity (how much).

Children 
ComplexNumber  A Number that has the form: x + yi, where x and y are RealNumbers and i is the square root of 1. 
 ImaginaryNumber  Any Number that is the result of multiplying a RealNumber by the square root of 1. 
 多極變量  a variable that describes energetical interactions between multipoles. 
 RealNumber  Any Number that can be expressed as a (possibly infinite) decimal, i.e. any Number that has a position on the number line. 