Average integral symbol

Question

Is there in LaTeX a symbol or a macro for the average integral with a horizontal slash? I know about \strokedint, but I'd prefer the dash to be horizontal.

Answer 1

This answer probably will not help you right now, but it should sometime in the future.

There is a unicode entry for that symbol U+2A0D FINITE PART INTEGRAL: ⨍ (your computer might or might not display this correctly. At least modern Linux distros should). The STIX font and unicode-math seem to support that symbol, so if you have them set up you can just use the symbol. As Will Robertson remarked below, unicode-math provides the \intbar command to access the symbol.

Answer 2

I found a solution here. You can use the following instructions, which must be included on the preamble.

\def\Xint#1{\mathchoice
{\XXint\displaystyle\textstyle{#1}}%
{\XXint\textstyle\scriptstyle{#1}}%
{\XXint\scriptstyle\scriptscriptstyle{#1}}%
{\XXint\scriptscriptstyle\scriptscriptstyle{#1}}%
\!\int}
\def\XXint#1#2#3{{\setbox0=\hbox{$#1{#2#3}{\int}$ }
\vcenter{\hbox{$#2#3$ }}\kern-.6\wd0}}
\def\ddashint{\Xint=}
\def\dashint{\Xint-}

The commands to execute those macros are \dashint and \ddashint for single dash and double dash, respectively.

EDIT: I tested the code given in the page, and the dash was a bit to the left of the integral, so I changed it slightly, substituting the .5 from the line \vcenter{\hbox{$#2#3$ }}\kern-.5\wd0}} with a .6 . It worked for me, if it doesn't exactly do it for you, experiment with the .5 to find exactly where you want the dash to be, adding (subtracting) from the number to place it more to the right (left).

Answer 3

There is a very useful site for this sort of questions. It is a hand-writing interface to the comprehensive LaTeX symbol list: you draw the symbol you are looking for in a box (using your mouse,...) and the software tries to recognise it. You can teach the software by telling it which one (if any) of its suggestions is the one you wanted.

I tried it with the average integral symbol and it suggested the command \fint in the esint package. That package seems to contain a number of ornamented integral signs.

Answer 4

I'm not aware of a pre-existing version of that sign. So you have to design it for yourself. I would suggest something like:

\newcommand*{\avint}{\mathop{\ooalign{$\int$\cr$-$}}}

\ooalign vertically overlaps symbols. Internally it creates a tabular environment. Thatswhy you need the \cr between the $\int$ and $-$.

edit: This example compiles and shows the correct sign:

\documentclass{article}
\newcommand*{\avint}{\mathop{\ooalign{$\int$\cr$-$}}}
\begin{document}
$\avint_{i=0}^{\infty} f(x)dx$ or
\[
\giint_{i=0}^{\infty} f(x)dx
\]
\end{document}