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[Solved] Modern Algebra Symbols

Posted: Fri Jun 08, 2018 2:22 am
by MH7
I have noticed that there are some symbols that are used in Modern (abstract) Algebra, that aren't necessarily listed in the math reference. "oplus", indicating a direct product between 2 groups, is one such example. I would like to track down a few others.

My most pressing need, is the sign for "is isomorphic to". (a tilde above an equal sign) How do I make this?

Re: Modern Algebra Symbols

Posted: Fri Jun 08, 2018 4:48 am
by UnklDonald418
Insert %Ux2245 into the appropriate place in your formula to display the character I believe you are needing.
To find other symbols, in the Math module select Tools>Symbols to open the Symbols dialog.
Select Special for Symbol Set and the click on Edit to open the Edit Symbols dialog.

Re: Modern Algebra Symbols

Posted: Fri Jun 08, 2018 5:10 am
by MH7
OK, that's really clunky, but it works. The only question is, how do I put a slash through it, to indicate "is not isomorphic to"?

Thank you.

Re: Modern Algebra Symbols

Posted: Fri Jun 08, 2018 6:15 am
by UnklDonald418
that's really clunky, but it works.
If you use the Edit Symbols dialog I mentioned, you can add the symbol to the list of Special symbols. Once on the list you can select it in the Symbols dialog and Insert it into your formula.
how do I put a slash through it, to indicate "is not isomorphic to"?
The Unicode value should be %Ux2247 but it doesn't seem to work so it may not be available in the Math module.

Re: Modern Algebra Symbols

Posted: Fri Jun 08, 2018 7:16 am
by Zizi64
My most pressing need, is the sign for "is isomorphic to". (a tilde above an equal sign) How do I make this?
I just tried it in my LibreOffice 5.4.7:

for the ≅ sign like character (it will be a composed character but not one standalone Unicode character):

Code: Select all

tilde "="  
For the "approximately equals" sign:

Code: Select all

simeq
And I can write Oplus characters in my LO. Maybe the working of this feature is depends on the installed Symbols character set. There are obsolete Symbols set in some version of the operating systems.
Oplus.png

Re: Modern Algebra Symbols

Posted: Fri Jun 08, 2018 11:49 am
by keme
The congruence/isomorphism symbol is hex unicode 2245.

Code: Select all

A boper %Ux2245 B
"Boper" is perhaps not strictly necessary. It makes the symbol behave like a binary operator, which improves layout in some situations (and may also aid in discovering structural inconsistencies in your formula).

Re: Modern Algebra Symbols

Posted: Fri Jun 08, 2018 4:04 pm
by MH7
Thank you everyone for the suggestions. Regarding the "clunky" use of the special characters, I say that it was clunky, because in the formula editor, it would not allow me to directly insert using the Unicode. I did, indeed, have to add it to the special characters menu, under "edit". And it seems that is a limited palette.

Now, the pressing issue, is the question that was missed in here... Where is the "not isomorphic to" symbol? How can I put a slash through what we've just discovered, to negate its value?

Re: Modern Algebra Symbols

Posted: Fri Jun 08, 2018 4:17 pm
by MrProgrammer
MH7 wrote:Where is the "not isomorphic to" symbol?
Perhaps you can use:
tilde "≠"
If this solved your problem please go to your first post use the Edit button and add [Solved] to the start of the title. You can select the green checkmark icon at the same time.

Re: Modern Algebra Symbols

Posted: Fri Jun 08, 2018 4:56 pm
by MH7
It works OK (doesn't quite look right) in the document, but not in the math editor.

Re: Modern Algebra Symbols

Posted: Fri Jun 08, 2018 5:22 pm
by UnklDonald418
how do I put a slash through it, to indicate "is not isomorphic to"?
I found it in the Arial Unicode MS font. Set the Edit Symbol dialog like this
notIsomorphic.png
Select the symbol and push the Add button. Then it should appear in the Symbols dialog Special list.

Re: Modern Algebra Symbols

Posted: Sat Jun 09, 2018 6:26 pm
by MH7
THank you, that will do it.