classification of complex numbers
The set of all complex numbers and many of its subsets may bepartitioned (classified) into two subsets by certain criterion of the numbers.
A. F i r s t c l a s s i f i c a t i o n :
Complex numbers contain
- 1.
algebraic numbers
- 2.
transcendental numbers
Algebraic numbers contain
- 1.
algebraic integers
( algebraic numbers)
- 2.
algebraic fractions (fractional algebraic numbers)
Algebraic integers contain
- 1.
rational integers
- 2.
non-rational integers
Algebraic fractions contain
- 1.
rational fractions
- 2.
non-rational fractions
Transcendental numbers contain
- 1.
real transcendental numbers
- 2.
imaginary transcendental numbers
B. S e c o n d c l a s s i f i c a t i o n :
Complex numbers contain
- 1.
real numbers (http://planetmath.org/RealNumber) (the set )
- 2.
imaginary numbers (i.e. non-real complex numbers)
Real numbers contain
- 1.
rational numbers
(the set )
- 2.
irrational numbers
Rational numbers contain
- 1.
integers (http://planetmath.org/Integer) (the set )
- 2.
fractional numbers
Imaginary numbers contain
- 1.
pure imaginary numbers (with real part
0)
- 2.
other imaginary numbers (with real part )
One can also combine the criterions of A and B; thus e.g.the irrational numbers consist of the algebraic irrational numbers andthe irrational numbers.
In , any of the sets , and may be partitioneded into positive numbers, negative numbers and 0 (http://planetmath.org/Null).
Number-theoretically, the set consists of four of integers:
the number 0,
the units of (only and ),
the prime numbers (),
the composite numbers ()