I want to write an equation as follows.
angle A + angle B = angle C.
When I write it in formula << %angle A >>, the angle is coming with two oblique lines with an arc in between them. Can I get the (more standard) angle symbol with just two lines (a horizontal and an oblique line) in librewriter?
%angle returns U+2222 SPHERICAL ANGLE. There is no other symbol defined for the other angle symbols in Unicode. You must enter them manually:
Alt+X for U+2221 MEASURED ANGLEAlt+X for U+2220 ANGLETo show the community your question has been answered, click the ✓ next to the correct answer, and “upvote” by clicking on the ^ arrow of any helpful answers. These are the mechanisms for communicating the quality of the Q&A on this site. Thanks!
I am getting 2221≈ or 2220≈ upon typing 2221 Alt + X. I am using a Mac Pro so I typed 2220 Option + X. I want the Unicode Character “∠” (U+2220).
You should have mentioned your OS!
If problem solved, be kind enough to click on the gray check mark at top left of answer (only once, even if apparently nothing happens!)
I still don’t understand the solution. How do I enter “∠” symbol manually in writer? Copy-paste from another source?
The Alt+X is a general trick in LO. It is valid in Writer, Draw, Math, Calc and Impress.
Under MacOS, for historical reasons dating back to MacOS Classic, the role of modifier keys may be permuted. Ctrl should read ⌘. The “option” key was labelled ⌥ but Linux and Windows make a difference between left and right “alt” keys (respectively labelled Alt and Alt Gr). If it does not work with Option, try with Ctrl not ⌘.
If it still does not work, Insert>Special Character, Font: OpenSymbol ant type 2220 in the Hexadecimal: U+ box.
Thanks. It worked differently in Mac. But your suggestion helped. This is from my librewriter file.
∠A +∠B = ∠C
Try OOoFBTools. The extension features inter alia a couple of virtual keyboards, including one with math symbols. The angle symbol (U+2220) is there.
Thanks. Your suggestion made me look into my mac keyboard and it helped me find other answers too.
Glad that you have found a solution. Still, the extension is worth trying. It has a lot of great features. Kinda diamond in the dust 
Since Version 5.1 there is a method available to enter any unicode character within the Math Editor using the Unicode codepoint toggle (as detailed by @ajlittoz in his answer). That method, as detailed below, works on both Linux & Windows.
I no longer use a Mac, so cannot comment on that, but the suggested method in the link is slightly different to ajlittoz’s method (I’ve tried both under Linux & both work):
To obtain any Unicode codepoint in the default font, Liberation Serif for
text, enter the code point and with cursor after the last character toggle
to display the glyph with <alt>+x. E.g. for U+00B0 DEGREE SIGN, enter
U+00B0 and then <alt>+x to toggle to °
You can also use the Symbols button and define a new entry in the Special
category for the degree sign, but I find the Unicode toggle to be more
direct.
I’m puzzled by ‘%angle’, and would like to know where it is documented. I assume that it is an Element, but can find zero mention of it’s use within the Help (f1). The glyph that it produces is also different to all other similar glyphs and is NOT yet proves to be U+2222 SPHERICAL ANGLE. However, I cannot find which Unicode char it does come from.
U+2220 => ∠ (ANGLE)
U+2221 => ∡ (MEASURED ANGLE)
U+2222 => ∢ (SPHERICAL ANGLE)
U+2993 => ⦓ (LEFT ARC LESS-THAN BRACKET)
U+2996 => ⦖ (DOUBLE RIGHT ARC LESS-THAN BRACKET)
PS
It is possible in Base since at least v3.4 to enter any unicode character using the UNICHAR(number) function. However, this is the Math Editor (full disclosure: I’ve never used it in anger) and that function cannot be used there.
PPS
The reason for the different appearance of ‘%angle’ cf U+2222 SPHERICAL ANGLE is that the latter uses the system font set via the menu whilst ‘%angle’ overrides the system font & force-uses OpenSymbol (those two glyphs differ a lot for this char) (I prefer the OpenSymbol glyph).
(tested using LO Version: 5.2.7.2 under Devuan Linux 2.1 (ascii))
If this helps then please tick the answer (
)
…and/or show you like it with an uptick (∧)
Thank you so much, ajlittoz. I eventually found it within the index of a v4.x PDF download. The resultant symbol was shown within the PDF & I could copy it there (but not within my Math window). My utility (KCharSelect) then identified it as a ∢ U+2222 SPHERICAL ANGLE.
I still maintain that the Math-window glyph looks nothing like the KCharSelect glyph, even though both are using the same font. Well, whatever.
In my case, the glyph look the same both when typed in as a plain char or as an %angle entity (with the Liberation Serif font).
Ah! Different font used for %angle.
I confirm that %angle and U+2222Alt X don’t display as the same symbol, even in Math. The reason is %angle is automatically taken from OpenSymbol while the other is taken from the current font, probably the one for text, which is Liberation Serif in my default configuration. It is also possible that it comes from a substitution font if the symbol is not in the font proper.
In KCharSelect, you can change the font and it is clear this is not the same glyph in OpenSymbol (default for Math symbols) and other fonts. It even differs between members of the same family (Mono, Sans, Serif).
The question has been adequately answered for Windows and Linux. In Mac, I can type the angle symbol from “Show emoji and symbols” . There are Math symbols in them. I click Math symbols, find the symbol that I want to use and then doubleclick on the symbol. I was not aware of this feature before. Thanks @ajlittoz, @gabix, @AlexKemp for the discussion that helped me find the solution.
∠ABC > ∠ABD.
(I took the liberty to slightly modify your answer, adding Linux – since my box is a Linux one – and spelling correctly Alex Kemp’s name who is a different user than Alex straight) ajlittoz