Python-Tutorial-with-Excercise/Python Numbers/Python Numbers 7 at main · digitechit07/Python-Tutorial-with-Excercise · GitHub

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
Python Numbers
Number Types
int: integral number

float: floating point number, usually IEEE 754 (64 bits, base 2)

complex: complex number, implemented as two floats

decimal.Decimal: floating point number stored in base 10, arbitrary precision

fractions.Fraction: rational, numerator/denominator; automatically compute the greatest common divisor (GCD) to simplify the fraction

Number Tower
The numbers module is specified by the PEP 3141 – A Type Hierarchy for Numbers.

numbers.Number: base class

numbers.Complex: Add real, imag, conjugate()

numbers.Real: subclass of Complex; add many float operations.

numbers.Rational: subclass of Real; add numerator and denominator attributes

numbers.Integral: subclass of Rational

Subclasses:

numbers.Number: int, float, complex, decimal.Decimal, fractions.Fraction

numbers.Complex: int, float, complex, fractions.Fraction

numbers.Real: int, float, fractions.Fraction

numbers.Rational: int, fractions.Fraction

numbers.Integral: int

int, float, complex methods and attributes:

conjugate()

imag

real

int and Fraction attributes:

denominator

numerator

Conversions in Python
int(obj) and float(obj) accept:

int

float

decimal.Decimal

fractions.Fraction

bytes

str

int(obj) rounds towards zero (ROUND_DOWN, ex: int(0.9) == 0 and int(-0.9) == 0).

But int(obj) and float(obj) reject:

complex

complex(obj) accepts:

int

float

complex

decimal.Decimal

fractions.Fraction

str

But complex(obj) rejects:

bytes

decimal.Decimal(obj) accepts:

int

float

decimal.Decimal

str

But decimal.Decimal(obj) rejects:

complex

fractions.Fraction

bytes

fractions.Fraction(obj) accepts:

int

float

decimal.Decimal

fractions.Fraction

str (ex: "1" or "1/2")

But fractions.Fraction(obj) rejects:

complex

bytes