[Tex/LaTex] Symbol for “not absolutely continuous” in Latex

symbols

I have trouble finding the symbol which indicates that two measure are not absolutely continuous i.e. the negation of $\mu \ll \nu$. Anyone has an idea how to write this?

Edit 1:

Best Answer

The \centernot package is made for that:

\documentclass{article}
\usepackage{amsmath,centernot}

\newcommand{\nll}{\centernot{\ll}}

\begin{document}

$a\ll b$

$a\nll b$

\end{document}

Related Solutions

[Tex/LaTex] How to write Rudin’s symbol for absolute continuity of measures

If one doesn't want to load the whole lot of mathabx, that changes the shape of many symbols, it's possible to load only the one needed, see Importing a single symbol font from a different font.

The definition would be

\DeclareMathSymbol{\Lt}{3}{matha}{"CE}

using the unicode-math name or, if the alternative way by pisymbol is preferred,

\newcommand{\Lt}{\Pimathsymbol[\mathrel]{matha}{"CE}}

The complete series of declarations in the preamble should be

\DeclareFontFamily{U}{matha}{\hyphenchar\font45}
\DeclareFontShape{U}{matha}{m}{n}{
  <-6> matha5 <6-7> matha6 <7-8> matha7
  <8-9> matha8 <9-10> matha9
  <10-12> matha10 <12-> matha12
  }{}
% \DeclareFontShape{U}{matha}{m}{n}{
%   <5> <6> <7> <8> <9> <10> gen * matha
%   <10.95> matha10 <12> <14.4> <17.28>
%   <20.74> <24.88> matha12
%   }{}

\DeclareSymbolFont{matha}{U}{matha}{m}{n}
\DeclareMathSymbol{\Lt}{3}{matha}{"CE}

If your TeX distribution is fairly recent you can leave out the commented lines (starting with %); otherwise, uncomment them and delete the similar ones above. It has to do with the presence of the Type1 (scalable) versions of the mathabx fonts.

With the alternative method that doesn't reserve a math alphabet, the code to write in the preamble is

\usepackage{pifont}
\DeclareFontFamily{U}{matha}{\hyphenchar\font45}
\DeclareFontShape{U}{matha}{m}{n}{
  <-6> matha5 <6-7> matha6 <7-8> matha7
  <8-9> matha8 <9-10> matha9
  <10-12> matha10 <12-> matha12
  }{}
\makeatletter
\newcommand\Pimathsymbol[3][\mathord]{%
  #1{\@Pimathsymbol{#2}{#3}}}
\def\@Pimathsymbol#1#2{\mathchoice
  {\@Pim@thsymbol{#1}{#2}\tf@size}
  {\@Pim@thsymbol{#1}{#2}\tf@size}
  {\@Pim@thsymbol{#1}{#2}\sf@size}
  {\@Pim@thsymbol{#1}{#2}\ssf@size}}
\def\@Pim@thsymbol#1#2#3{%
  \mbox{\fontsize{#3}{#3}\Pisymbol{#1}{#2}}}
\makeatother
\newcommand{\Lt}{\Pimathsymbol[\mathrel]{matha}{"CE}}

For the \DeclareFontShape command it's the same as before.

[Tex/LaTex] Symbol for “rotate around axis”

Here is a tikz version which automatically gets you all the flexibility inherent in tikz such as rotating the symbol to be appropriate for the axis, adjusting the line style, colors, arrow style, etc...

enter image description here

Further Enhancement:

Automatically rotate the symbol to be along the path.
Provide a style setting that can be used to customize the symbol

Code:

\documentclass[border=2pt]{standalone}
\usepackage{tikz}

\newcommand{\AxisRotator}[1][rotate=0]{%
    \tikz [x=0.25cm,y=0.60cm,line width=.2ex,-stealth,#1] \draw (0,0) arc (-150:150:1 and 1);%
}

\begin{document}
\begin{tikzpicture}
\draw (0,0)  -- (3,0)  node [midway] {\AxisRotator};
\draw (0,0)  -- (0,-3) node [midway] {\AxisRotator[rotate=-90]};
\draw (0,-3) -- (3,0)  node [midway] {\AxisRotator[rotate=60]};
\end{tikzpicture}
%
\begin{tikzpicture}
\draw (0,0)  -- (3,0)  node [midway] {\AxisRotator[x=0.2cm,y=0.4cm,->,densely dotted]};
\draw (0,0)  -- (0,-3) node [midway] {\AxisRotator[x=0.2cm,y=0.4cm,->,rotate=-90,blue, dashed]};
\draw (0,-3) -- (3,0)  node [midway] {\AxisRotator[x=0.2cm,y=0.4cm,->,rotate=60, red ]};
\end{tikzpicture}
\end{document}