# Trigonometric arc

How to be codes for trigonometric arc AB like that:

( not using kpfonts ). Thanks.

• Welcome! What have you tried? Where have you looked? Why are you stuck? If you are particular about fonts, which are you using? A minimal example would be the ideal way to provide some of this information. – cfr Feb 8 '16 at 2:30
• Are you using XeTeX or LuaTeX? – Joel Reyes Noche Feb 8 '16 at 12:16
• Thank you for replying. I can use kpfonts to make it but all fonts in the document changed. Is there a way to make that symbol but reserving all the other fonts. I don't know using XeTex or LuaTex. – Exdata Feb 8 '16 at 13:42

You could draw this with tikz:

\documentclass{article}

\usepackage{amsmath,tikz}

\newcommand{\curvearc}{\tikz[trim left]{\draw[->] (0,0) to[bend left] (1em,0);}}

\begin{document}

$$\stackrel{\curvearc}{AB}$$

\end{document}


If you would like the width of this arrow symbol to vary with the material underneath and then you can use the following more complicated definition:

\documentclass{article}

\usepackage{amsmath,tikz}

\newlength{\curvearclength}
\newcommand{\curvearcover}[1]{\mathpalette\curvearcoverhelper{#1}}
\newcommand{\curvearcoverhelper}[2]{%
\settowidth{\curvearclength}{$$#1#2$$}%
\setlength{\curvearclength}{0.6\curvearclength}%
\stackrel{\tikz[trim left]{\draw[->] (0,0) to[bend left]
(\the\curvearclength,0);}}{#1#2}}

\begin{document}

$$\curvearcover{AB}$$

\bigskip

$$\curvearcover{IJ}$$

\bigskip

$$\scriptstyle\curvearcover{AB}$$

\end{document}

• \newcommand*\curvearc[2][1em]{\overset{\tikz[trim left]\draw[->](0,0)to[bend left]({#1},0);}{#2}} might be more practical. – Manuel Feb 10 '16 at 18:34
• @Manuel Indeed - code now added to make the measuring automatic. – Andrew Swann Feb 12 '16 at 12:37

\usepackage{fourier}

Then

$\wideOarc{AB}$

However, as Andrew Swann noted in a comment, loading the fourier package changes all the fonts in the document.