Changing size of square symbol to bullet symbol

Question

Is it possible to resize the \blacksquare command to the size of the \bullet command?

Additionally, is it possible to resize \bullet to \circ?

Thank you.

Answer 1

• we create a variable for the width of \bullet

• we use resizebox

   \documentclass[border=3mm]{standalone}
   \usepackage{amssymb}
   \usepackage{mathtools}
   \begin{document}
   \newlength{\mylength}
   \settowidth{\mylength}{$\blacksquare$}
   \the\mylength : $\blacksquare$
   \settowidth{\mylength}{$\bullet$}
   \the\mylength : $\bullet$
   \resizebox{\mylength}{!}{$\blacksquare$}
   \end{document}
  

Answer 2

Several packages have these options. For example, MnSymbol

\documentclass{article}

\usepackage{MnSymbol}

\begin{document}

$a\circ b\bullet c\filledsquare d$

\end{document}

Slightly different is fdsymbol:

\documentclass{article}

\usepackage{fdsymbol}

\begin{document}

$a\circ b\bullet c\smallblacksquare d$

\end{document}