When using the <chem> tag to write a formula like "CO2 + C -> 2 CO" , the plus sign ends up as superscript to CO2, as if it was a charge (reported on it.wp). It's the first formula you see when you open the editor to add one.
And also: 2.5 should give 2 * 5, and it works. But 2 . 5, with spaces, should give 2.5, and it doesn't, so there is no way to add decimal fractions.
| Status | Subtype | Assigned | Task | ||
|---|---|---|---|---|---|
| Resolved | Physikerwelt | T159735 Chemistry formulae ignore significant spaces, opposite to LateX source | |||
| Resolved | manfredschaefer | T140217 Adjust texvcjs to prevent whitespace modifications in ce-tags | |||
| Resolved | None | T166936 In MW 1.29, Visual editor displays chemical equations incorrectly (plus sign on same level as index number) | |||
| Resolved | Pkra | T158509 Chemical bonds not working | |||
| Open | None | T184879 Fix \ce grammar with macros above/below texts | |||
| Resolved | manfredschaefer | T184880 texvcjs - Find solution for other commands within \ce | |||
| Resolved | Physikerwelt | T188879 Remove texvc | |||
| Resolved | Physikerwelt | T185033 Fix texvcjs grammar for X^{2+} |
That the plus sign on the line has a meaning, while the plus sign displayed as superscript means something else?
Of course. The question is why do you expect something else than superscript? This is the way how it works. If you need it different, use "{CO2} + C -> 2 CO".
@IKhitron If there is a space between CO2 and +, I would expect + not being a superscript. If there isn't a space between CO2 and +, I would expect + to be a superscript.
I guess I'm expecting something different because of the spaces (I'm writing it CO2 + , not CO2+).
I would have never thought about using parentheses. If anyone else actually writing and understanding formulas would naturally know that, please decline this task.
Again, we need to compare to LateX. If it's the same - it's their problem, not our. If it isn't - there is computation bug here.
But I think it is a wrong behavior, because if I write CO2+, it changes to "CO²+". I believe these two are just switched in the computation. The last predefined formula is broken too, in the opposite way.
Well, checked in LateX \ce. There is a bug, indeed. Something ignores spaces in the parsing. It can be also in other example:
2.5 should give 2 * 5, and it works. But 2 . 5, with spaces, should give 2.5, and it doesn't, so there is no way to add decimal fractions.
Math markup goes inside <math>...</math>. Chemistry markup goes inside <math chem>...</math> or <chem>...</chem>. All these tags use TeX.
The TeX code has to be put literally: MediaWiki templates, predefined templates, and parameters cannot be used within math tags: pairs of double braces are ignored and "#" gives an error message. However, math tags work in the then and else part of #if, etc
It seems to be a pure texvcjs bug. If someone provides a test case, we can probably fix it in the grammar. What I understand is that the input
curl -X POST "https://en.wikipedia.org/api/rest_v1/media/math/check/chem" -H "accept: application/json" -H "Content-Type: multipart/form-data" -F "q=\ce{2.5}"
currently results in
"checked": "{\\ce {2.5}}",
and
curl -X POST "https://en.wikipedia.org/api/rest_v1/media/math/check/chem" -H "accept: application/json" -H "Content-Type: multipart/form-data" -F "q=\ce{2 . 5}"
results in
"checked": "{\\ce {2 . 5}}",
See https://en.wikipedia.org/api/rest_v1/#/Math/post_media_math_check__type_
No doubt about the additional space between \ce and the argument is stupid and also the extra curly brackets, but that's another issue.
Also CO2 + C -> 2 CO becomes {\\ce {CO2 + C -> 2 CO}} so no issue here, or?