ETSI's Bug Tracker - Part 01: TTCN-3 Core Language |
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| ID | Project | Category | View Status | Date Submitted | Last Update |
| 0006695 | Part 01: TTCN-3 Core Language | Clarification | public | 04-03-2014 16:49 | 06-01-2015 19:10 |
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| Reporter | Jacob Wieland - Spirent | |
| Assigned To | Gyorgy Rethy | |
| Priority | normal | Severity | minor | Reproducibility | always |
| Status | closed | Resolution | fixed | |
| Platform | | OS | | OS Version | |
| Product Version | v4.5.1 (published 2013-04) | |
| Target Version | v4.7.1 (published 2015-06) | Fixed in Version | v4.7.1 (published 2015-06) | |
| Clause Reference(s) | 7.1.1 |
| Source (company - Author) | Testing Technologies - Jacob Wieland |
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| Summary | 0006695: restriction on arithmetic operators should be put in a restriction section or should be dropped altogether |
| Description | the restriction on the arithmetic float operators are only mentioned in a NOTE, but not in a proper restriction.
It is unclear why these restrictions exist in the first place as in other languages, clear semantics of using the special values as operands exist:
Infinity * -Infinity == -Infinity
Infinity * Infinity == Infinity
-Infinity * -Infinity == Infinity
Infinity * positive_number == Infinity
Infinity * 0.0 == NaN
Infinity * negative_number == -Infinity
-Infinity * positive_number == -Infinity
-Infinity * 0.0 == NaN
-Infinity * negative_number == Infinity
X * NaN == NaN
Infinity / (Infinity or NaN or -Infinity) == NaN
Infinity / positive_number == Infinity
Infinity / negative_number == -Infinity
-Infinity / positive_number == -Infinity
-Infinity / negative_number == Infinity
-Infinity / (Infinity or NaN or -Infinity) == NaN
(Infinity or NaN or -Infinity) / Infinity == NaN
(Infinity or NaN or -Infinity) / -Infinity == NaN
NaN / X == NaN
X / NaN == NaN
Therefore, I think the restriction should be dropped.
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| Steps To Reproduce | |
| Additional Information | |
| Tags | No tags attached. |
| Relationships | |
| Attached Files |  CR6695_update_proposal.docx (14,971) 10-04-2014 14:54
http://oldforge.etsi.org/mantis/file_download.php?file_id=3006&type=bug
CR6695_update_proposal-v3.docx (13,695) 07-10-2014 15:57
http://oldforge.etsi.org/mantis/file_download.php?file_id=3103&type=bug |
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| Issue History |
| Date Modified | Username | Field | Change |
| 04-03-2014 16:49 | Jacob Wieland - Spirent | New Issue | |
| 07-04-2014 16:46 | Gyorgy Rethy | Note Added: 0011947 | |
| 07-04-2014 16:57 | Gyorgy Rethy | Assigned To | => Axel Rennoch |
| 07-04-2014 16:57 | Gyorgy Rethy | Status | new => assigned |
| 10-04-2014 14:54 | Axel Rennoch | File Added: CR6695_update_proposal.docx | |
| 10-04-2014 14:55 | Axel Rennoch | Assigned To | Axel Rennoch => Gyorgy Rethy |
| 10-04-2014 14:58 | Axel Rennoch | Note Added: 0012012 | |
| 10-04-2014 14:58 | Axel Rennoch | Status | assigned => confirmed |
| 20-06-2014 11:40 | Gyorgy Rethy | Project | TTCN-3 Change Requests => Part 01: TTCN-3 Core Language |
| 20-06-2014 11:40 | Gyorgy Rethy | Product Version | => v4.5.1 (published 2013-04) |
| 20-06-2014 11:40 | Gyorgy Rethy | Target Version | => v4.7.1 (published 2015-06) |
| 06-10-2014 10:24 | Gyorgy Rethy | Note Added: 0012219 | |
| 06-10-2014 10:24 | Gyorgy Rethy | Note Edited: 0012219 | bug_revision_view_page.php?bugnote_id=12219#r67 |
| 06-10-2014 10:24 | Gyorgy Rethy | Note Edited: 0012219 | bug_revision_view_page.php?bugnote_id=12219#r68 |
| 06-10-2014 12:01 | Jacob Wieland - Spirent | Note Added: 0012228 | |
| 06-10-2014 15:38 | Gyorgy Rethy | Note Added: 0012233 | |
| 06-10-2014 15:39 | Gyorgy Rethy | Assigned To | Gyorgy Rethy => Jens Grabowski |
| 07-10-2014 15:57 | Jens Grabowski | File Added: CR6695_update_proposal-v3.docx | |
| 07-10-2014 15:57 | Jens Grabowski | Assigned To | Jens Grabowski => Gyorgy Rethy |
| 07-10-2014 15:57 | Jens Grabowski | Status | confirmed => assigned |
| 07-10-2014 15:57 | Jens Grabowski | Status | assigned => resolved |
| 07-10-2014 15:57 | Jens Grabowski | Resolution | open => fixed |
| 06-01-2015 19:10 | Gyorgy Rethy | Note Added: 0012658 | |
| 06-01-2015 19:10 | Gyorgy Rethy | Status | resolved => closed |
| 06-01-2015 19:10 | Gyorgy Rethy | Fixed in Version | => v4.7.1 (published 2015-06) |
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Notes |
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stf478: check how operations are handled in other languages. |
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Problem: a note prevents arithmetic float operators for special float values infinity, -infinity and not_a_number
Analysis:
a) IEEE 754:2008 standard allow operation (ch 6.1):
Infinity * -Infinity == -Infinity
Infinity * Infinity == Infinity
-Infinity * -Infinity == Infinity
Infinity * positive_number == Infinity
Infinity * negative_number == -Infinity
-Infinity * positive_number == -Infinity
-Infinity * negative_number == Infinity
Infinity / positive_number == Infinity
Infinity / negative_number == -Infinity
-Infinity / positive_number == -Infinity
-Infinity / negative_number == Infinity
b) IEEE 754:2008 standard defines exceptions (i.e. invalid_operation=NaN, 7.1):
Infinity * 0.0 == NaN
-Infinity * 0.0 == NaN
X * NaN == NaN
Infinity / (Infinity or NaN or -Infinity) == NaN
-Infinity / (Infinity or NaN or -Infinity) == NaN
(Infinity or NaN or -Infinity) / Infinity == NaN
(Infinity or NaN or -Infinity) / -Infinity == NaN
NaN / X == NaN
X / NaN == NaN
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Using float in TTCN-3 is twofold:
- they are data sent in message fields (e.g. signal strength in dB); in this context special values can also appear
- used as numbers in the TTCN-3 code (behaviour), e.g. timer values and durations (delays), calculating averages etc. In this context operations make sense, but using special values make not.
We have to decide which way to go: making the note a mandatory text or allow operations an special values?
*It needs STF discussion*
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Treating them differently would be confusing, I think. |
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Add a sentence that operations of IEEE 754 to be followed. |
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