-
Notifications
You must be signed in to change notification settings - Fork 62
Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
Merge pull request #317 from buildingSMART/78-testcase-floating-point…
…-numbers-tolerance 78 testcase floating point numbers tolerance
- Loading branch information
Showing
66 changed files
with
96 additions
and
35 deletions.
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
File renamed without changes.
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
File renamed without changes.
File renamed without changes.
File renamed without changes.
File renamed without changes.
File renamed without changes.
File renamed without changes.
File renamed without changes.
File renamed without changes.
File renamed without changes.
File renamed without changes.
File renamed without changes.
File renamed without changes.
File renamed without changes.
File renamed without changes.
File renamed without changes.
File renamed without changes.
File renamed without changes.
File renamed without changes.
File renamed without changes.
File renamed without changes.
File renamed without changes.
File renamed without changes.
File renamed without changes.
File renamed without changes.
File renamed without changes.
File renamed without changes.
File renamed without changes.
File renamed without changes.
File renamed without changes.
File renamed without changes.
File renamed without changes.
File renamed without changes.
File renamed without changes.
File renamed without changes.
File renamed without changes.
File renamed without changes.
File renamed without changes.
File renamed without changes.
File renamed without changes.
File renamed without changes.
File renamed without changes.
File renamed without changes.
File renamed without changes.
File renamed without changes.
File renamed without changes.
File renamed without changes.
File renamed without changes.
File renamed without changes.
File renamed without changes.
File renamed without changes.
File renamed without changes.
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
File renamed without changes.
File renamed without changes.
File renamed without changes.
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
File renamed without changes.
File renamed without changes.
File renamed without changes.
File renamed without changes.
File renamed without changes.
File renamed without changes.
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -0,0 +1,61 @@ | ||
| # Tolerance value in IDS | ||
|
|
||
| ## Equality tolerance | ||
|
|
||
| Because of rounding errors, a tolerance value must always be considered for the equality of floating-point numbers (doubles in ids:simpleValue and xs:restriction). | ||
|
|
||
| To support both low numbers, like an area of a wire expressed in square meters, and high numbers, like a length of a railway, the IDS uses both a relative and a fixed component, following the formula: | ||
|
|
||
| `x == v ⇒ (v - abs(v) × ϵ - ϵ) < x < (v + abs(v) × ϵ + ϵ)` | ||
| with a tolerance value being: `ϵ = 1.0e⁻⁶` | ||
|
|
||
| The table below demonstrates characteristic ranges of values within the tolerance: | ||
|
|
||
| |v|lower bound<br>`(v - abs(v) × ε - ε)`| upper bound<br>`(v + abs(v) × ε + ε)`| absolute delta| | ||
| |---:|-------------:|-------------:|--:| | ||
| | 100000.0 | 99999.899999 | 100000.100001 | 0.200002 | | ||
| | 10000.0 | 9999.989999 | 10000.010001 | 0.020002 | | ||
| | 1000.0 | 999.998999 | 1000.001001 | 0.002002 | | ||
| | 100.0 | 99.999899 | 100.000101 | 0.000202 | | ||
| | 10.0 | 9.999989 | 10.000011 | 2.2E-05 | | ||
| | 1.0 | 0.999998 | 1.000002 | 4E-06 | | ||
| | 0.1 | 0.0999989 | 0.1000011 | 2.2E-06 | | ||
| | 0.01 | 0.00999899 | 0.01000101 | 2.02E-06 | | ||
| | 0.001 | 0.000998999 | 0.001001001 | 2.002E-06 | | ||
| | 0.0001 | 0.0000989999 | 0.0001010001 | 2.0002E-06 | | ||
| | 0.00001 | 0.00000899999 | 0.00001100001 | 2.00002E-06 | | ||
| | 0.000001 | -0.000000000001 | 0.000002000001 | 2.000002E-06 | | ||
| | 0.0000001 | -0.0000009000001 | 0.0000011000001 | 2.0000002E-06 | | ||
| | 0 | -0.000001 | 0.000001 | 2.0E-06 | | ||
| | -0.0000001 | -0.0000011000001 | 0.0000009000001 | 2.0000002E-06 | | ||
| | -0.000001 | -0.0000020000 | 0.000000000001 | 2.000002E-06 | | ||
| | -0.00001 | -0.0000110000 | -0.00000899999 | 2.00002E-06 | | ||
| | -0.0001 | -0.0001010001 | -0.0000989999 | 2.0002E-06 | | ||
| | -0.001 | -0.0010010010 | -0.000998999 | 2.002E-06 | | ||
| | -0.01 | -0.0100010100 | -0.00999899 | 2.02E-06 | | ||
| | -0.1 | -0.1000011000 | -0.0999989 | 2.2E-06 | | ||
| | -1.0 | -1.0000020000 | -0.999998 | 4E-06 | | ||
| | -10.0 | -10.0000110000 | -9.999989 | 2.2E-05 | | ||
| | -100.0 | -100.0001010000 | -99.999899 | 0.000202 | | ||
| | -1000.0 | -1000.0010010000 | -999.998999 | 0.002002 | | ||
| | -10000.0 | -10000.0100010000 | -9999.989999 | 0.020002 | | ||
| | -100000.0 | -100000.1000010000 | -99999.899999 | 0.200002 | | ||
| | -1000000.0 | -1000001.0000010000 * | -999998.999999 | 2.000002 | | ||
|
|
||
| \* If the least significant digits are beyond the precision of a IEEE74 double (approximately 17 digits), it might result in a false positive. For example, -1000001.00000100001 would still pass as being equal to -1000000.0, even though being below the lower bound. | ||
|
|
||
| Note: the tolerance value is not configurable, as it is specific only for rounding errors, not for construction-related tolerances, for which users need to provide an explicit range. | ||
|
|
||
| ## Range tolerance | ||
|
|
||
| Adding tolerance to range checks would open up all kinds of strange edge cases like 41.999958 being both in the range 42-50 inclusive, but also < 42 exclusive. For that reason, **exclusive ranges should be shrunk, while inclusive ranges should be stretched**. | ||
|
|
||
| For example: | ||
| - `x > 0 ⇒ x > 1.0e⁻⁶` | ||
| - `x >= 0 ⇒ x >= -1.0e⁻⁶` | ||
|
|
||
| If a numeric range constraint's spread is lower than the agreed limit, the Audit-tool should raise a warning. | ||
|
|
||
| # | ||
|
|
||
| Note: the history of these agreements can be traced in the history of [issue 78](https://github.com/buildingSMART/IDS/issues/78), [issue 36](https://github.com/buildingSMART/IDS/issues/36), and in [the summary by @giuseppeverduciALMA](https://github.com/buildingSMART/IDS/blob/0d50fd8f2dbd5b388f6fafb67da255cc3ce2b4ca/Documentation/tolerance.md). |