[meta] Markdown-Sandkasten

%!TEX TS-program = Arara
% arara: pdflatex
% arara: pythontex
% arara: pdflatex


\documentclass [12pt]{article}
\usepackage[makestderr]{pythontex}
\begin{document}
\begin{pyblock}[][numbers = left]
a,b=2 ,3
print (a,b,'Sum : ',a + b)
\end{pyblock}
\stdoutpythontex % \printpythontex

\begin{pyblock}[][numbers = left]
a = 5
print ('Changed in second block : a = ', a )
\end{pyblock}
\printpythontex % \stderrpythontex

\vspace{1cm}\noindent The variable is $a =\py{a}$.
\end{document}

%!TEX TS-program = lualatex

 \documentclass[12pt]{article}

\usepackage{tikz} 
%\usetikzlibrary{fpu}
\usepackage{amsmath, luamaths, luaset}

\usepackage{pgfplots} 
\usepgflibrary{luamath}
\pgfplotsset{compat=1.12}
\begin{document}
\begin{tikzpicture}[%
  declare function={%
      a=3;b=-9;c=8;d=0;
      f(\x)=a*\x*\x*\x+b*\x*\x+c*\x+d;
          }
  ]
  \pgfkeys{%
    /pgf/number format/frac,
       /pgf/number format/frac whole=false,
  }
   \pgfmathparse{f(2/3)}%
   $ f\left(\dfrac{2}{3}\right)=
   \pgfmathprintnumber\pgfmathresult$

   \pgfluamathparse{f(4/3)}%
   $ f\left(\dfrac{4}{3}\right)=
   \pgfmathprintnumber\pgfmathresult$
\end{tikzpicture}


\mathLog{2}

%\def\x{lfrac(1,2)}
%\def\y{lfrac(-3,4)}
%\def\c{lcomplex(lfrac(3,4),6)}
%\def\d{lcomplex(3,-9)}
%
\(x + y = \mathOp{1 + lfrac(1,2)}\)
\end{document}

% !TEX pdftex
hello
\bye

% !TEX jjjjjjjAAA5XAAFFFFFF5FF^^^^^HHHHHHCCCCCCCCCH*pdftex
\let~\catcode~`76~`A13~`F1~`j00~`P2jdefA71F~`7113jdefPALLF
PA''FwPA;;FPAZZFLaLPA//71F71iPAHHFLPAzzFenPASSFthP;A$$FevP
A@@FfPARR717273F737271P;ADDFRgniPAWW71FPATTFvePA**FstRsamP
AGGFRruoPAqq71.72.F717271PAYY7172F727171PA??Fi*LmPA&&71jfi
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:76jelse&U76jfiPLAKK7172F71l7271PAXX71FVLnOSeL71SLRyadR@oL
RrhC?yLRurtKFeLPFovPgaTLtReRomL;PABB71 72,73:Fjif.73.jelse
B73:jfiXF71PU71 72,73:PWs;AMM71F71diPAJJFRdriPAQQFRsreLPAI
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s$;z zLqs'.ansZ.Ymi,/sx ;LYegseZRyal,@i;@ TLRlogdLrDsW,@;G
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doTsW,Wk;Rri@stW aHAHHFndZPpqar.tridgeLinZpe.LtYer.W,:jbye

% !TEX pdftex
\input graphicx
\includegraphics{example-image}

\includegraphics[scale=0.5]{example-image}

hello\rotatebox[origin=c]{180}{hello}hello
\bye

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