Saving in $\LaTeX$

Question

When I save the following notebook code as $\LaTeX$,

In[1]:= DSolve[y'[x] + x y'[x]^2 == 1, y, x]

Out[1]= {{y -> 
   Function[{x}, 
    C[1] + 1/2 (-2 Sqrt[1 + 4 x] - 2 Log[1 - Sqrt[1 + 4 x]])]}, {y -> 
   Function[{x}, 
    C[1] + 1/2 (2 Sqrt[1 + 4 x] - 2 Log[1 + Sqrt[1 + 4 x]])]}}

I get this $\LaTeX$ code:

%% AMS-LaTeX Created by Wolfram Mathematica 8.0 : www.wolfram.com

\documentclass{article}
\usepackage{amsmath, amssymb, graphics, setspace}
\newcommand{\mathsym}[1]{{}}
\newcommand{\unicode}[1]{{}}
\newcounter{mathematicapage}
\begin{document}
    \begin{doublespace}
    \noindent\(\pmb{\text{DSolve}[y'[x]+x y'[x]{}^{\wedge}2==1,y,x]}\)
    \end{doublespace}
    \begin{doublespace}
    \noindent\(\left\{\left\{y\to \text{Function}\left[\{x\},C[1]+\frac{1}{2} \left(-2              
    \sqrt{1+4 x}-2 \text{Log}\left[1-\sqrt{1+4 x}\right]\right)\right]\right\},\left\{y\to
    \text{Function}\left[\{x\},C[1]+\frac{1}{2} \left(2 \sqrt{1+4 x}-2
    \text{Log}\left[1+\sqrt{1+4 x}\right]\right)\right]\right\}\right\}\)
    \end{doublespace}
    \end{document}

I would like to have $$ instead of

\begin{doublespace}
\noindent

i.e., as an ordinary $\TeX$ file.

Answer 1

The way you do this - by saving the whole notebook with un-formatted In/Out cells - will get you a file with non-traditional working Mathematica notation. For example you will get square brackets for functions instead of round ones and capitalized functions names. If your goal is just to get a nicely formatted formula in $\TeX$ form, you could use this (for your 1st equation):

In[1]:= f = First[y /. DSolve[y'[x] + x y'[x]^2 == 1, y, x]];
        TeXForm[f[x]]

Out[1]//TeXForm=
c_1+\frac{1}{2} \left(-2 \sqrt{4 x+1}-2 \log \left(1-\sqrt{4 x+1}\right)\right)

If you paste the output in the body of your $\TeX$ file between $$ you'll get a nice formula:

If you would like to save the whole document you need to apply some formatting to it, depending on what you exactly need. For example turning an output cell into text cell will result in wrapping the formulas in \( ... \) , which is an equivalent of $...$ in $\LaTeX$.

Answer 2

What I find convenient: in Mathematica

probi = Exp[Sum[-τ((Subscript[x,i,k] - Subscript[x,j,k])^2)/2,
        {i,j}∈Subscript[Edge,k]]] HoldForm[Sqrt[τ/(2Pi)]]^Subscript[N,i]

Export["formula1.tex", (HoldForm[logP[X,τ]] == Log[probi]//PowerExpand)//TeXForm, "text"]

and in $\LaTeX$:

$$ \input{formula1.tex} $$

This results with the formula: $$\text{logP}(X,\tau )=\sum _{\{i,j\}\in \text{Edge}_k} \frac{1}{2} (-\tau ) \left(x_{i,k}-x_{j,k}\right){}^2+N_i \log \left(\sqrt{\frac{\tau }{2 \pi }}\right)$$

If the formula is large use breqn.

\begin{dmath}
\scriptstyle
\input{formula1.tex}
\end{dmath}`