composition of functions (math) in LaTeX2e
Jose Capco
In math mode.. how do I write f composed with g.. I can write it with
$f \circ g$ but the
circle that comes in between f and g looks a bit bigger than the usual
circle we use in math.. or is it only me who thinks this way? Is it the
standard way in LaTeX to write $f\circ g$ as composition.. or is there
a better and more standard symbol for the circle in between?
Sincerely,
Jose Capco
Dan
Jose Capco wrote:
> Dear NG,
>
> In math mode.. how do I write f composed with g.. I can write it with
> $f \circ g$ but the
> circle that comes in between f and g looks a bit bigger than the usual
> circle we use in math.. or is it only me who thinks this way?
It's only you :-) Seriously: see below.
>Is it the
> standard way in LaTeX to write $f\circ g$ as composition..
Yes.
If you don't like a symbol (or don't know how to get it) the standard
reference is the "Comprehensive LaTeX Symbol List" which should be easy
to google.
Dan
Angus Rodgers
>Jose Capco wrote:
>> In math mode.. how do I write f composed with g.. I can write it with
>> $f \circ g$ but the
>> circle that comes in between f and g looks a bit bigger than the usual
>> circle we use in math.. or is it only me who thinks this way?
>It's only you :-)
Only him, me, Bourbaki, Herstein, Halmos, Rudin, and Mac Lane!
I no longer have a copy of the first few volumes of Bourbaki,
but the composition symbol in Roger Godement, /Algebra/ (1963;
English translation Kershaw, London 1969) is much smaller than
the LaTeX \circ symbol, and it looks "right" to my eyes.
The same goes for Herstein, /Topics in Algebra/ (2nd ed. Wiley
1975). And the composition symbol in Halmos, /Naive Set Theory/
(Van Nostrand? 1960, reprinted by Springer 1974) is so small as
to be almost a dot. Rudin, /Principles of Mathematical Analysis/
(3rd ed. McGraw-Hill 1976) is similar to Bourbaki/Godement and
Herstein. Finally, the same goes for Mac Lane, /Categories for
the Working Mathematician (1st ed. Springer 1971).
I'm sure there are many more examples, all from the mainstream.
These were only the first 5 I thought to check; and a hit rate
of 5 out of 5 (from 5 different publishers) is pretty good, I
thought, so I didn't bother to check any more - sorry! :)
>Seriously [...]
(I hope I didn't miss the point.)
--
Angus Rodgers
(twirlip@ eats spam; reply to angusrod@)
Contains mild peril
Enrico Gregorio
In the Computer Modern fonts, that's the symbol; who are we to judge
the Grand Wizard? :-)
But here is a hack. I am too lazy to implement it in pure LaTeX:
\newcommand{\compcent}[1]{\vcenter{\hbox{$#1\circ$}}}
\newcommand{\comp}{\mathbin{\mathchoice
{\compcent\scriptstyle}{\compcent\scriptstyle}
{\compcent\scriptscriptstyle}{\compcent\scriptscriptstyle}}}
Now $f\comp g$ should give you the small circle you wanted.
Ciao
Enrico
Dan
My point was I wasn't being serious. The serious part of the answer you
omitted and dit not address.
All the examples you mentioned probably don't use the CM fonts.
I, too, think it is too large _in the cm fonts_, but not so much that I
would make an effort to do anything about it. You could try another
font set, but I don't know which one. The comprehensive symbol list I
mentioned would be a starting point.
Dan