Talk:ISO 31-11

message: Okay, now we are getting really deep into the Unicode standard, but shouldn't the perpendicular operator be ⟂ (U+27C2 PERPENDICULAR) instead of ⏊ (U+23CA DENTISTRY SYMBOL LIGHT UP AND HORIZONTAL, as currently used in the article)? --Abdull 22:15, 28 May 2006 (UTC)
replies: text: Well spotted! My mistake. The character I actually wanted to use was ⊥ (U+22A5 UP TACK). I took a wrong turn in the code charts, was heading for APL symbols, but actually ended up in Japanese dendistry symbols ... a likely peril in the age of mega character sets. UP TACK is widely supported in existing fonts and seems the appropriate Unicode 4.0 character for the perpendicular symbol to me. A dedicated ⟂ (U+27C2 PERPENDICULAR) was added only quite recently (Unicode 4.1) and I'm not fully convinced yet that there was a good case to disambiguate between the two. The glyphs for UP TACK and PERPENDICULAR are for all practical purposes identical, and the difference between a constant and an operator only matters in TeX-style math-rendering implementations that try to automatically insert whitespace near operators, which is irrelevant for HTML, Wikipedia, etc. So I prefer to use UP TACK instead of PERPENDICULAR for the moment, because the latter is not yet widely implemented in fonts. Markus Kuhn 19:19, 29 May 2006 (UTC)
thread_title:  Unicode UP TACK versus PERPENDICULAR 

message: I'm seeing ? where I think other character should be. In the mathematical symbols table it has the line:
:⟨⟩ |?a+b?c | ac+bc, angle brackets
Shouldn't that read:
:<> |<a+b>c | ac+bc, angle brackets
Or am I missing something.
:The font your particular browser uses probably still lacks glyphs for the two characters U+27E8 (MATHEMATICAL LEFT ANGLE BRACKET) and U+27E9 (MATHEMATICAL RIGHT ANGLE BRACKET). The angle brackets have, unfortunately, a somewhat confused history in Unicode. They were for a while mistaken to be CJK wide characters, and disambiguated from these (unnecessarily) rather late. Markus Kuhn 22:01, 3 July 2006 (UTC)
replies: text:  It does seem to be a font issue, but I wonder if many people will have the same issue. I'm on Mac OS X 10.4.6 and though I have all of the standard internet/web fonts installed (and then some) I still don't have any that have a glyph for this character. I wonder if a note should be added  to show what it should roughly look like using another more commonly existing glyph (like simply the greater than less than charaacter glyphs like I used above). I don't think the characters in the main text should be changed, but just suggest a note be added, since I don't imagine I'm the only one to encounter this problem. As the fonts improve and proliferate, the note could then be taken away. --Cplot 23:13, 3 July 2006 (UTC)

text: Please report what exact browser and font you are using, and I'll be happy to investigate and report the problem upstream. I'd rather see this fixed in the font and not in the article. Markus Kuhn 08:41, 5 July 2006 (UTC)
thread_title:  Angle brackets 

message: I have used math tags for angle brackets and perpendicular signs. I think that this is a better and easier solution that works for everybody.
Size is not optimum, but could be tweaked, as I did with \perp. 
Check and change back if you do not like.
Regards,
Jakubi 17:14, 9 September 2007 (UTC)
thread_title:  use of math tags 

message: There may be some existing sister article that covers the following; if so we should identify it and create a prominent link.  If not, it would be useful to include in this article an indication of how a reader might create the glyphs discussed here.  Obviously, different typesetting systems vary, but the three that seem straightforwardly useful (where they exist) are: HTML entities; Unicode codepoint; Tex escape sequence.  I believe that adding a column (or perhaps adding to an existing column) with this "how to represent" information is useful and encyclopedic. LotLE×talk 19:50, 18 January 2010 (UTC)
thread_title:  Creating the glyphs 

message: See Talk:Table of mathematical symbols#Why is the equivalent symbol not here....???
--222.64.27.154 (talk) 01:42, 20 March 2010 (UTC)
thread_title:  Equivalent symbol....??? 

message: Could someone that has access to the ISO standard check the notation for matrices, pls. ISO_31-11#Matrices gives A, while the NIST Guide (p.35) gives simply A (or, more precisely, A). Thanks! Fgnievinski (talk) 02:06, 30 March 2010 (UTC)
thread_title:  Matrices 

message: I don't mean to be pedant, but most symbols in this article are sans serif, and I'm not sure that's intended. I wish I had access to the ISO standard to check, but looking at the NIST Guide, it says for example (p.34): "Symbols for vectors are boldface italic, symbols for tensors are sans-serif bold italic". Though not explicitly stated, I interpret that as "Symbols for vectors are seriffed boldface italic, symbols for tensors are sans-serif bold italic", otherwise there is no way to distinguish vectors from tensors. As another example, the Guide says (p.34): "symbols for quantities and variables [are] italic; symbols for units [are] roman". According to the article Roman type, in Typography "roman" is ambiguous -- it can mean either:
* a synonym for serif;
* the upright counterpart of an italic typeface, regardless of whether the type design is seriffed or a sans serif.
Should we rewrite the article replacing, e.g., A by A (i.e., A by A)?
Fgnievinski (talk) 02:41, 30 March 2010 (UTC)
thread_title:  Sans serif suspicious 

message: It looks kind of weird on the article, but its fine in the discussion page. It does have something to do with the font
It looks nothing like the TEX equivalent. 
[]  — Preceding unsigned comment added by 180.215.170.131 (talk) 12:54, 12 January 2012 (UTC)
thread_title:  (Belongs to) ∈ Looks ugly on the main page 

message: Does anyone know if the ISO standard uses an open phi (\varphi) or closed phi (\phi) for cylindrical and spherical coordinates?  Also, is the answer the same for ISO 80000-2? JonH (talk) 07:00, 25 October 2012 (UTC)
replies: text: The symbol used by ISO 80000-2 (p25) looks to me like the open version, \varphi. The same symbol is used for both spherical and cylindrical co-ordinates.  Dondervogel 2 (talk) 17:16, 25 July 2013 (UTC)
replies: text: Thanks for the reply.  So it seems that Wikipedia is using the correct symbol in this case. JonH (talk) 18:08, 25 July 2013 (UTC)
replies: text:  The correct symbol indeed for phi, but not for theta (also open according to 80000-2).  What bothers me is more is the insistence throughout Wikipedia on italicising the mathematical constants e, π and i, which according to ISO should be upright. Dondervogel 2 (talk) 19:05, 25 July 2013 (UTC)
thread_title:  Phi 

message: I agree with slawekb.  This particular standard might be superseded, but in modern standards, mathematical constants like e, pi and i are upright. Dondervogel 2 (talk) 09:40, 9 May 2015 (UTC)
replies: text: Yes, in the ISO 80000-2 that supersedes this one, mathematical constants are upright as well.  Sławomir Biały (talk) 12:22, 9 May 2015 (UTC)
replies: text: It doens't matter what the recomendation is... Wikipedia follows standard practice, which is to universally ignore this recomendation. -- User:Edokter  14:18, 9 May 2015 (UTC)
replies: text: Yes, in practice thus recommendation is seldom applied.  But it is what it is, and this is an article about the standard, which includes typesetting conventions, not standard practice on Wikipedia. If you would like to add a comment to the article that ISO 31-11 is universally ignored in this point (appropriately sourced) then go ahead.  But we don't get to make up our own version of the ISO standard just because it disagrees with conventions on Wikipedia.  That just makes no sense at all.  Sławomir Biały (talk) 16:14, 9 May 2015 (UTC)
thread_title:  Inappropriate italicisation