-
-
Notifications
You must be signed in to change notification settings - Fork 94
Expand file tree
/
Copy pathRoundingMode.php
More file actions
93 lines (81 loc) · 3.09 KB
/
RoundingMode.php
File metadata and controls
93 lines (81 loc) · 3.09 KB
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
<?php
declare(strict_types=1);
namespace Brick\Math;
/**
* Specifies rounding behavior by defining how discarded digits affect the returned result when an exact value cannot
* be represented at the requested scale.
*/
enum RoundingMode
{
/**
* Asserts that the requested operation has an exact result, hence no rounding is necessary.
*
* If this rounding mode is specified on an operation that yields a result that
* cannot be represented at the requested scale, a RoundingNecessaryException is thrown.
*/
case Unnecessary;
/**
* Rounds away from zero.
*
* Always increments the digit prior to a nonzero discarded fraction.
* Note that this rounding mode never decreases the magnitude of the calculated value.
*/
case Up;
/**
* Rounds towards zero.
*
* Never increments the digit prior to a discarded fraction (i.e., truncates).
* Note that this rounding mode never increases the magnitude of the calculated value.
*/
case Down;
/**
* Rounds towards positive infinity.
*
* If the result is positive, behaves as for Up; if negative, behaves as for Down.
* Note that this rounding mode never decreases the calculated value.
*/
case Ceiling;
/**
* Rounds towards negative infinity.
*
* If the result is positive, behaves as for Down; if negative, behaves as for Up.
* Note that this rounding mode never increases the calculated value.
*/
case Floor;
/**
* Rounds towards "nearest neighbor" unless both neighbors are equidistant, in which case round up.
*
* Behaves as for Up if the discarded fraction is >= 0.5; otherwise, behaves as for Down.
* Note that this is the rounding mode commonly taught at school.
*/
case HalfUp;
/**
* Rounds towards "nearest neighbor" unless both neighbors are equidistant, in which case round down.
*
* Behaves as for Up if the discarded fraction is > 0.5; otherwise, behaves as for Down.
*/
case HalfDown;
/**
* Rounds towards "nearest neighbor" unless both neighbors are equidistant, in which case round towards positive infinity.
*
* If the result is positive, behaves as for HalfUp; if negative, behaves as for HalfDown.
*/
case HalfCeiling;
/**
* Rounds towards "nearest neighbor" unless both neighbors are equidistant, in which case round towards negative infinity.
*
* If the result is positive, behaves as for HalfDown; if negative, behaves as for HalfUp.
*/
case HalfFloor;
/**
* Rounds towards the "nearest neighbor" unless both neighbors are equidistant, in which case rounds towards the even neighbor.
*
* Behaves as for HalfUp if the digit to the left of the discarded fraction is odd;
* behaves as for HalfDown if it's even.
*
* Note that this is the rounding mode that statistically minimizes
* cumulative error when applied repeatedly over a sequence of calculations.
* It is sometimes known as "Banker's rounding", and is chiefly used in the USA.
*/
case HalfEven;
}