I proposed the symbol for symmetric difference in https://github.com/metamath/set.mm/pull/1613#issuecomment-619592865 , namely U+25B3, after a quick google search for "unicode triangle". On the html pages, it looks a bit too large (ideally, it should be the same size as for \cap and \cup, especially the lower horizontal line). But I cannot find the exact unicode for $\triangle$. The wikipedia page just cited is wrong: the symbol used in the first column corresponds to the LaTeX \triangle, but the columns "HTML" and "Unicode" correspond to other symbols.
(By the way: since the symmetric difference is commutative, it's nice to have a left-right symmetric symbol, so \Delta is not good.) Benoît On Monday, April 27, 2020 at 8:15:05 AM UTC+2, [email protected] wrote: > > FWIW, this Wikipedia list corresponds TeX's \triangle with U+2206: > https://en.wikipedia.org/wiki/List_of_mathematical_symbols_by_subject > Mario Carneiro <[email protected] <javascript:>> wrote: > > I'm not so sure about that. It looks like the primary meaning of that > > codepoint is "increment operator", used for small discrete changes, > which > > usually is an actual Delta (and read as such aloud). Visually, it also > > shows the same typographic weight changes as is common with Delta that > are > > absent in the white triangle symbol. > > > > As for using the triangle symbol for geometry, well let's just say > that's a > > conversation for another day. > > > > > > On Sun, Apr 26, 2020 at 10:12 PM Thierry Arnoux <[email protected] > <javascript:>> > > wrote: > > > > > You’re right! Actually, the code I used is x2206, which is listed as > > > “Symmetrical Difference”, so I believe it shall be the correct one. > > > https://codepoints.net/U+2206 > > > > > > This is a different code from Uppercase Delta (code x394), I wanted to > > > describe the shape - thanks for correcting me! > > > > > > We can still use the x25B3 code (triangle) for geometry! ;-) > > > BR, > > > _ > > > Thierry > > > file:///home/benoit/T%C3%A9l%C3%A9chargements/test.html > > > > > > Le 27 avr. 2020 à 11:44, Mario Carneiro <[email protected] > <javascript:>> a écrit : > > > > > > > > > I think there is a unicode symbol for symmetric difference that is a > white > > > upward pointing triangle (U+25B3 △), not an upper case Delta (which > looks a > > > bit different due to weight changes along the glyph). > > > > > > -- > > > You received this message because you are subscribed to the Google > Groups > > > "Metamath" group. > > > To unsubscribe from this group and stop receiving emails from it, send > an > > > email to [email protected] <javascript:>. > > > To view this discussion on the web visit > > > > https://groups.google.com/d/msgid/metamath/08094638-8C7B-47D9-814C-4E621E5C5B94%40gmx.net > > > > < > https://groups.google.com/d/msgid/metamath/08094638-8C7B-47D9-814C-4E621E5C5B94%40gmx.net?utm_medium=email&utm_source=footer> > > > > > . > > > > > -- You received this message because you are subscribed to the Google Groups "Metamath" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/metamath/2549dbe2-98bf-4153-8ba6-1d1cf3f6c0d9%40googlegroups.com.
