Extensible leftarrow accent above math symbols

by murray   Last Updated September 11, 2019 22:23 PM

What better ways are there than what I show below for using a left arrow as a math accent to go over single and groups of symbols, and in a harmonious way?


\linespread{1.1} % just to display output here more clearly



Accent single character with left arrow:


$\reverse{\sigma}$ \quad Arrow too short, too light, too small?

$\longreverse{\sigma}$ \quad Arrow too long and heavy!


Accent multiple characters with left arrow:


$\xreverse{\sigma \ast \tau}$ \quad Use \verb!\xreverse!: arrow definitely too short. 

$\longreverse{\sigma \ast \tau}$ \quad Use \verb!\longreverse!: arrow long enough, but perhaps too heavy?


Want to use  better arrows in the alternative to \dots
\[(\sigma \ast \tau)^{\leftarrow} \simeq \reverse{\tau} \ast \reverse{\sigma}
\dots that instead puts the long left arrow over the whole group of 3 symbols:


\item $\longreverse{\sigma \ast \tau} \simeq \reverse{\tau} \ast \reverse{\sigma}$ \quad Use \verb!\longreverse! on left, \verb!\reverse! on right.

\item $\longreverse{\sigma \ast \tau} \simeq \longreverse{\tau} \ast \longreverse{\sigma}$ \quad Use \verb!\longreverse! for all.



leftarrow accents

I'd strongly prefer a method that avoids using TikZ or other drawing methods. And I need a method that will be relatively robust when a different font family (e.g., lucidabr, mathtimepro2) is used insstead of newtx.

I am aware of Configurable and Extensible Accents (Arrows, Dots, Vectors) and the item Dashed left arrow over symbol that is referenced by the accepted answer to it.

Tags : arrows accents

Related Questions

Combination of arrows with and without label

Updated August 31, 2016 08:09 AM

Draw circle with nodes and arrows on it

Updated November 19, 2018 16:23 PM

How do I attach arrows together?

Updated November 07, 2017 23:23 PM