Drawing dashed `\subseteq` symbol

Question

I am trying to draw a dashed \subseteq symbol:

(in contrast to \not\subseteq or \varsubsetneq and \nsubseteq from the amsfonts package) but having no success. Is there any known way to do this? Also detexify was not able to find that symbol.

Answer 1

This one just paints white lines over the existing \subseteq and calls it \notsubseteq. As currently defined, it will not scale to other sizes. If that is a primary issue, perhaps the OP will let me know.

\documentclass{article}
\usepackage{stackengine,xcolor}
\stackMath
\def\notsubseteq{\mathrel{
  \stackinset{l}{0pt}{c}{}{\wrule[2pt]{5pt}{.5pt}}{
  \stackinset{l}{1.6pt}{c}{}{\wrule[-4pt]{.5pt}{10pt}}{
  \stackinset{l}{3.35pt}{c}{}{\wrule[-4pt]{.5pt}{10pt}}{
  \stackinset{l}{5.1pt}{c}{}{\wrule[-4pt]{.5pt}{10pt}}{
 \subseteq}}}}
}}
\newcommand\wrule[3][0pt]{\textcolor{white}{\rule[#1]{#2}{#3}}}
\begin{document}
\[ A \subseteq B \]
\[ A \notsubseteq B \]
\end{document}

Here is a version that tries to cut the symbol at perpendicular intervals. I redefine the white to red in the last version to show the overlays.

\documentclass{article}
\usepackage{stackengine,xcolor,graphicx}
\stackMath
\def\notsubseteq{\mathrel{
  \stackinset{l}{0pt}{c}{}{\wrule[2pt]{5pt}{.5pt}}{
  \stackinset{l}{1.6pt}{c}{}{\wrule[-10pt]{.5pt}{3pt}}{
  \stackinset{l}{0.5pt}{c}{1.5pt}{\rotatebox[origin=center]{45}{\wrule[2pt]{.5pt}{3pt}}}{
  \stackinset{l}{0.5pt}{c}{}{\rotatebox[origin=center]{-45}{\wrule[-5pt]{.5pt}{3pt}}}{
  \stackinset{l}{3.35pt}{c}{}{\wrule[-4pt]{.5pt}{10pt}}{
  \stackinset{l}{5.1pt}{c}{}{\wrule[-4pt]{.5pt}{10pt}}{
 \subseteq}}}}}}
}}
\newcommand\wrule[3][0pt]{\textcolor{white}{\rule[#1]{#2}{#3}}}
\begin{document}
\[ A \subseteq B \]
\[ A \notsubseteq B \]
\renewcommand\wrule[3][0pt]{\textcolor{red}{\rule[#1]{#2}{#3}}}%
\[ A \notsubseteq B \]
\end{document}