Math & Science ⇒ [solved] Why \overrightarrow is not working for me?

[dedec0]

I am using LaTeX in a Debian computer, with a good number of things installed beyound the basic. To compile my tex files, i use the command 'pdflatex'.

This code compiles without error:

Code: Select all

\documentclass[12pt]{article}
\usepackage{amssymb}

\usepackage{amsmath}
\usepackage[T1]{fontenc}
\usepackage[utf8]{inputenc}
\usepackage[portuguese]{babel}
 
\usepackage{hyphenat}
\hyphenation{mate-mática recu-perar}

\begin{document}
    \pagestyle{empty}
	\paragraph
	{
	    \textbf{10.13.} aaaaaa, aaaaaa aaaaaaaaaaa, 
aaa aa $\textit{aa} \equiv \textit{aa}$ a $\textit{EF} \equiv
 \textit{GH}$ sãa aaaa aaaaa aa aaaaaaaaa aaaaa
aaaaaaa, a $\textit{M}$, $\textit{N}$, $\textit{P}$ e 
$\textit{Q}$ sãa aa aaaaaa aéaaaa aaa aaaaaaaaa
 $\textit{AE}$, $\textit{BF}$, $\textit{CG}$ e 
$\textit{DH}$, raaaaaaaaaaaaaa, aaaãa $\textit{aa}
 \equiv \textit{aa}$.
	}

	\paragraph
	{
	    \textbf{09.15.} Aa aaaaaa aaa aaaa aaaaa aaaaa
aaaaa aa aaaaaa aaa, aaaaaaaaa: 
	}
	    \subparagraph
	    {
	       %\overrightarrow{AB}%(a) $\overrightarrow{AE}$
 %- \overrightarrow{\textit{ED}} + \overrightarrow{\textit{EB}} $;
	       a
	    }

\end{document}

with pdflatex giving this output:

Code: Select all

This is pdfTeX, Version 3.14159265-2.6-1.40.17 (TeX Live 2016/Debian) (preloaded format=pdflatex)
 restricted \write18 enabled.
entering extended mode
(./x.tex
LaTeX2e <2017/01/01> patch level 3
Babel <3.9r> and hyphenation patterns for 4 language(s) loaded.
(/usr/share/texlive/texmf-dist/tex/latex/base/article.cls
Document Class: article 2014/09/29 v1.4h Standard LaTeX document class
(/usr/share/texlive/texmf-dist/tex/latex/base/size12.clo))
(/usr/share/texlive/texmf-dist/tex/latex/amsfonts/amssymb.sty
(/usr/share/texlive/texmf-dist/tex/latex/amsfonts/amsfonts.sty))
(/usr/share/texlive/texmf-dist/tex/latex/amsmath/amsmath.sty
For additional information on amsmath, use the `?' option.
(/usr/share/texlive/texmf-dist/tex/latex/amsmath/amstext.sty
(/usr/share/texlive/texmf-dist/tex/latex/amsmath/amsgen.sty))
(/usr/share/texlive/texmf-dist/tex/latex/amsmath/amsbsy.sty)
(/usr/share/texlive/texmf-dist/tex/latex/amsmath/amsopn.sty))
(/usr/share/texlive/texmf-dist/tex/latex/base/fontenc.sty
(/usr/share/texlive/texmf-dist/tex/latex/base/t1enc.def))
(/usr/share/texlive/texmf-dist/tex/latex/base/inputenc.sty
(/usr/share/texlive/texmf-dist/tex/latex/base/utf8.def
(/usr/share/texlive/texmf-dist/tex/latex/base/t1enc.dfu)
(/usr/share/texlive/texmf-dist/tex/latex/base/ot1enc.dfu)
(/usr/share/texlive/texmf-dist/tex/latex/base/omsenc.dfu)))
(/usr/share/texlive/texmf-dist/tex/generic/babel/babel.sty
(/usr/share/texlive/texmf-dist/tex/generic/babel-portuges/portuges.ldf
(/usr/share/texlive/texmf-dist/tex/generic/babel/babel.def)))
(/usr/share/texlive/texmf-dist/tex/latex/hyphenat/hyphenat.sty) (./x.aux)
(/usr/share/texlive/texmf-dist/tex/latex/amsfonts/umsa.fd)
(/usr/share/texlive/texmf-dist/tex/latex/amsfonts/umsb.fd) [1{/var/lib/texmf/fo
nts/map/pdftex/updmap/pdftex.map}] (./x.aux) ) </home/user/.texlive2016/texmf-v
ar/fonts/pk/ljfour/jknappen/ec/ecbi1200.600pk> </home/user/.texlive2016/texmf-v
ar/fonts/pk/ljfour/jknappen/ec/ecbx1200.600pk></usr/share/texlive/texmf-dist/fo
nts/type1/public/amsfonts/cm/cmsy10.pfb>
Output written on x.pdf (1 page, 18699 bytes).
Transcript written on x.log.

But when i uncomment the last part of the above file, just adding a simple "\overrightarrow{AB}" to it (note the rest of the line is a comment), transforming it in:

Code: Select all

\documentclass[12pt]{article}
\usepackage{amssymb}

\usepackage{amsmath}
\usepackage[T1]{fontenc}
\usepackage[utf8]{inputenc}
\usepackage[portuguese]{babel}
 
\usepackage{hyphenat}
\hyphenation{mate-mática recu-perar}

\begin{document}
    \pagestyle{empty}
	\paragraph
	{
	    \textbf{10.13.} aaaaaa, aaaaaa aaaaaaaaaaa, aaa aa $\textit{aa} \equiv \textit{aa}$ a $\textit{EF} \equiv \textit{GH}$ sãa aaaa aaaaa aa aaaaaaaaa aaaaaaaaaaaa, a $\textit{M}$, $\textit{N}$, $\textit{P}$ e $\textit{Q}$ sãa aa aaaaaa aéaaaa aaa aaaaaaaaa $\textit{AE}$, $\textit{BF}$, $\textit{CG}$ e $\textit{DH}$, raaaaaaaaaaaaaa, aaaãa $\textit{aa} \equiv \textit{aa}$.
	}

	\paragraph
	{
	    \textbf{09.15.} Aa aaaaaa aaa aaaa aaaaa aaaaaaaaaa aa aaaaaa aaa, aaaaaaaaa: 
	}
	    \subparagraph
	    {
	       \overrightarrow{AB}%(a) $\overrightarrow{AE}$ %- \overrightarrow{\textit{ED}} + \overrightarrow{\textit{EB}} $;
	       a
	    }

\end{document}

pdflatex will give this output, with an error prompt:

Code: Select all

$ pdflatex x.tex 
This is pdfTeX, Version 3.14159265-2.6-1.40.17 (TeX Live 2016/Debian) (preloaded format=pdflatex)
 restricted \write18 enabled.
entering extended mode
(./x.tex
LaTeX2e <2017/01/01> patch level 3
Babel <3.9r> and hyphenation patterns for 4 language(s) loaded.
(/usr/share/texlive/texmf-dist/tex/latex/base/article.cls
Document Class: article 2014/09/29 v1.4h Standard LaTeX document class
(/usr/share/texlive/texmf-dist/tex/latex/base/size12.clo))
(/usr/share/texlive/texmf-dist/tex/latex/amsfonts/amssymb.sty
(/usr/share/texlive/texmf-dist/tex/latex/amsfonts/amsfonts.sty))
(/usr/share/texlive/texmf-dist/tex/latex/amsmath/amsmath.sty
For additional information on amsmath, use the `?' option.
(/usr/share/texlive/texmf-dist/tex/latex/amsmath/amstext.sty
(/usr/share/texlive/texmf-dist/tex/latex/amsmath/amsgen.sty))
(/usr/share/texlive/texmf-dist/tex/latex/amsmath/amsbsy.sty)
(/usr/share/texlive/texmf-dist/tex/latex/amsmath/amsopn.sty))
(/usr/share/texlive/texmf-dist/tex/latex/base/fontenc.sty
(/usr/share/texlive/texmf-dist/tex/latex/base/t1enc.def))
(/usr/share/texlive/texmf-dist/tex/latex/base/inputenc.sty
(/usr/share/texlive/texmf-dist/tex/latex/base/utf8.def
(/usr/share/texlive/texmf-dist/tex/latex/base/t1enc.dfu)
(/usr/share/texlive/texmf-dist/tex/latex/base/ot1enc.dfu)
(/usr/share/texlive/texmf-dist/tex/latex/base/omsenc.dfu)))
(/usr/share/texlive/texmf-dist/tex/generic/babel/babel.sty
(/usr/share/texlive/texmf-dist/tex/generic/babel-portuges/portuges.ldf
(/usr/share/texlive/texmf-dist/tex/generic/babel/babel.def)))
(/usr/share/texlive/texmf-dist/tex/latex/hyphenat/hyphenat.sty) (./x.aux)
(/usr/share/texlive/texmf-dist/tex/latex/amsfonts/umsa.fd)
(/usr/share/texlive/texmf-dist/tex/latex/amsfonts/umsb.fd)
! Missing $ inserted.
<inserted text> 
                $
l.29 \end{document}
                   
?

What is the problem here?

[Stefan Kottwitz]

Welcome to the forum!

The problem is, that it is a math command and has to be used in math mode:

$\overrightarrow{AB}$

Stefan

[dedec0]

But it did not work.The 'pdflatex' output for the file obtained with

Code: Select all

\subparagraph
	    {
	       $ \overrightarrow{AB} $
	    }

in that final part of the file is:

Code: Select all

$  pdflatex z.tex 
This is pdfTeX, Version 3.14159265-2.6-1.40.17 (TeX Live 2016/Debian) (preloaded format=pdflatex)
 restricted \write18 enabled.
entering extended mode
(./z.tex
LaTeX2e <2017/01/01> patch level 3
Babel <3.9r> and hyphenation patterns for 4 language(s) loaded.
(/usr/share/texlive/texmf-dist/tex/latex/base/article.cls
Document Class: article 2014/09/29 v1.4h Standard LaTeX document class
(/usr/share/texlive/texmf-dist/tex/latex/base/size12.clo))
(/usr/share/texlive/texmf-dist/tex/latex/amsfonts/amssymb.sty
(/usr/share/texlive/texmf-dist/tex/latex/amsfonts/amsfonts.sty))
(/usr/share/texlive/texmf-dist/tex/latex/amsmath/amsmath.sty
For additional information on amsmath, use the `?' option.
(/usr/share/texlive/texmf-dist/tex/latex/amsmath/amstext.sty
(/usr/share/texlive/texmf-dist/tex/latex/amsmath/amsgen.sty))
(/usr/share/texlive/texmf-dist/tex/latex/amsmath/amsbsy.sty)
(/usr/share/texlive/texmf-dist/tex/latex/amsmath/amsopn.sty))
(/usr/share/texlive/texmf-dist/tex/latex/base/fontenc.sty
(/usr/share/texlive/texmf-dist/tex/latex/base/t1enc.def))
(/usr/share/texlive/texmf-dist/tex/latex/base/inputenc.sty
(/usr/share/texlive/texmf-dist/tex/latex/base/utf8.def
(/usr/share/texlive/texmf-dist/tex/latex/base/t1enc.dfu)
(/usr/share/texlive/texmf-dist/tex/latex/base/ot1enc.dfu)
(/usr/share/texlive/texmf-dist/tex/latex/base/omsenc.dfu)))
(/usr/share/texlive/texmf-dist/tex/generic/babel/babel.sty
(/usr/share/texlive/texmf-dist/tex/generic/babel-portuges/portuges.ldf
(/usr/share/texlive/texmf-dist/tex/generic/babel/babel.def)))
(/usr/share/texlive/texmf-dist/tex/latex/hyphenat/hyphenat.sty)
No file z.aux.
(/usr/share/texlive/texmf-dist/tex/latex/amsfonts/umsa.fd)
(/usr/share/texlive/texmf-dist/tex/latex/amsfonts/umsb.fd)
! Illegal parameter number in definition of \reserved@a.
<to be read again> 
                   \crcr 
l.28 \end{document}
                   
?

[Stefan Kottwitz]

That's a different issue.

The syntax is

Code: Select all

\subparagraph{title} Now the text comes.

Same for \paragraph, \section etc. In the code above, the whole text including paragraph breaks (empty lines) are in the title.

Stefan

[dedec0]

Thank you for your comments. I used to make some latex files, years ago. But i have forgotten most of it. So i am practically a newbie today.

Anyway, this thread is solved. The problem was using a math command in the wrong place.