# Subscript under sum with dot

I have a problem with the subscript under a sum with dot, it changes the position of the subscript. Namely,

\documentclass[a4paper,12pt]{article}

\usepackage[english]{babel}
\usepackage{amsfonts}
\usepackage{amsthm}
\usepackage{amsmath}
\usepackage{amssymb}

\begin{document}
\begin{align}
\dot{\sum}_{i \in I}
\end{align}
\end{document}


places the subscript next to the sum instead of under it. Does anyone know how to fix this?

• Are you executing the command in inline or display-style math mode? – Mico May 13 '14 at 12:45
• Added the complete document. It was in the align environment (so not inline). – Vincent May 13 '14 at 12:47

Using an accent upon \sum makes it lose the nature of operator. You simply have to reinstate it:

\documentclass[a4paper,12pt]{article}
\usepackage{amsmath}

\newcommand{\dotsum}{\mathop{\dot\sum}}

\begin{document}
$\dotsum_{i \in I} \sum_{i \in I}$
\end{document}


The \sum next to \dotsum is just for checking the alignment.

\documentclass[a4paper,12pt]{article}

\usepackage[english]{babel}
\usepackage{amsfonts}
\usepackage{amsthm}
\usepackage{amsmath}
\usepackage{amssymb}

\begin{document}
\begin{align}
\sum\limits^{\text{\textbullet}}_{i \in I}
\end{align}
\end{document}


• Thanks for your help. The dot above the sum is only a bit to high. – Vincent May 13 '14 at 12:57