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
|
#!/usr/bin/env python3
# © Copyright 2021-2022, Scott Gasch
"""A class to represent a rate of change."""
from typing import Optional
class Rate(object):
"""A class to represent a rate of change."""
def __init__(
self,
multiplier: Optional[float] = None,
*,
percentage: Optional[float] = None,
percent_change: Optional[float] = None,
):
count = 0
if multiplier is not None:
if isinstance(multiplier, str):
multiplier = multiplier.replace('%', '')
m = float(multiplier)
m /= 100
self.multiplier: float = m
else:
self.multiplier = multiplier
count += 1
if percentage is not None:
self.multiplier = percentage / 100
count += 1
if percent_change is not None:
self.multiplier = 1.0 + percent_change / 100
count += 1
if count != 1:
raise Exception('Exactly one of percentage, percent_change or multiplier is required.')
def apply_to(self, other):
return self.__mul__(other)
def of(self, other):
return self.__mul__(other)
def __float__(self):
return self.multiplier
def __mul__(self, other):
return self.multiplier * float(other)
__rmul__ = __mul__
def __truediv__(self, other):
return self.multiplier / float(other)
def __add__(self, other):
return self.multiplier + float(other)
__radd__ = __add__
def __sub__(self, other):
return self.multiplier - float(other)
def __eq__(self, other):
return self.multiplier == float(other)
def __ne__(self, other):
return not self.__eq__(other)
def __lt__(self, other):
return self.multiplier < float(other)
def __gt__(self, other):
return self.multiplier > float(other)
def __le__(self, other):
return self < other or self == other
def __ge__(self, other):
return self > other or self == other
def __hash__(self):
return self.multiplier
def __repr__(self, *, relative=False, places=3):
if relative:
percentage = (self.multiplier - 1.0) * 100.0
else:
percentage = self.multiplier * 100.0
return f'{percentage:+.{places}f}%'
|
