> how can i make an arrow with two top? i have to insert it ON a character...
> it is the tensor symbol... thanks...
If you need an arrow over a _single_ character, use
\stackrel <space> \Rightarrow <down> X
where X is the character.
You can define a math macro for faster typing.
If you need the arrow over several chars, then use the attached
fill.sty package (put \usepackage{fill} in the preamble),
and use \overbrack{xy} in the formula
(you only need to write \overbrack{xy as lyx automatically adds the
closing } )
PS: Don't mix the two methods!
\ifx\@fill@loaded\undefined % pb avec dia.sty
% ======================================================================
% ======================== FLECHES =====================================
% ======================================================================
\newbox\@strutbox@
\setbox\@strutbox@\hbox{\vrule height8pt depth3pt width0pt}
\def\strut@{\copy\@strutbox@}
\def\overrightarrow{\mathpalette\overrightarrow@}
\def\overrightarrow@#1#2{\vbox{\ialign{$##$\cr
#1{-}\mkern-6mu\cleaders\hbox{$#1\mkern-2mu{-}\mkern-2mu$}\hfill
\mkern-6mu{\to}\cr\noalign{\kern-.2326ex\nointerlineskip}\hfil#1#2\hfil\cr}}}
\let\overarrow\overrightarrow
\def\overleftarrow{\mathpalette\overleftarrow@}
\def\overleftarrow@#1#2{\vbox{\ialign{$##$\cr
#1{\leftarrow}\mkern-6mu\cleaders\hbox{$#1\mkern-2mu{-}\mkern-2mu$}\hfill
\mkern-6mu{-}\cr\noalign{\kern-.2326ex\nointerlineskip}\hfil#1#2\hfil\cr}}}
\def\overleftrightarrow{\mathpalette\overleftrightarrow@}
\def\overleftrightarrow@#1#2{\vbox{\ialign{$##$\cr
#1{\leftarrow}\mkern-6mu\cleaders\hbox{$#1\mkern-2mu{-}\mkern-2mu$}\hfill
\mkern-6mu{\to}\cr\noalign{\kern-.2326ex\nointerlineskip}\hfil#1#2\hfil\cr}}}
\def\underrightarrow{\mathpalette\underrightarrow@}
\def\underrightarrow@#1#2{\vtop{\ialign{$##$\cr
\hfil#1#2\hfil\cr\noalign{\nointerlineskip}%
#1{-}\mkern-6mu\cleaders\hbox{$#1\mkern-2mu{-}\mkern-2mu$}\hfill
\mkern-6mu{\to}\cr}}}
\let\underarrow\underrightarrow
\def\underleftarrow{\mathpalette\underleftarrow@}
\def\underleftarrow@#1#2{\vtop{\ialign{$##$\cr
\hfil#1#2\hfil\cr\noalign{\nointerlineskip}#1{\leftarrow}\mkern-6mu
\cleaders\hbox{$#1\mkern-2mu{-}\mkern-2mu$}\hfill
\mkern-6mu{-}\cr}}}
\def\underleftrightarrow{\mathpalette\underleftrightarrow@}
\def\underleftrightarrow@#1#2{\vtop{\ialign{$##$\cr
\hfil#1#2\hfil\cr\noalign{\nointerlineskip}#1{\leftarrow}\mkern-6mu
\cleaders\hbox{$#1\mkern-2mu{-}\mkern-2mu$}\hfill
\mkern-6mu{\to}\cr}}}
\def\Overrightarrow{\mathpalette\Overrightarrow@}
\def\Overrightarrow@#1#2{\vbox{\ialign{$##$\cr
#1{=}\mkern-6mu\cleaders\hbox{$#1\mkern-2mu{=}\mkern-2mu$}\hfill
\mkern-6mu{\Rightarrow}\cr\noalign{\kern-.2326ex\nointerlineskip}\hfil\strut@#1#2\hfil\cr}}}
\let\Overarrow\Overrightarrow
\def\Overleftarrow{\mathpalette\Overleftarrow@}
\def\Overleftarrow@#1#2{\vbox{\ialign{$##$\cr
#1{\Leftarrow}\mkern-6mu\cleaders\hbox{$#1\mkern-2mu{=}\mkern-2mu$}\hfill
\mkern-6mu{=}\cr\noalign{\kern-.2326ex\nointerlineskip}\hfil\strut@#1#2\hfil\cr}}}
\def\Overleftrightarrow{\mathpalette\Overleftrightarrow@}
\def\Overleftrightarrow@#1#2{\vbox{\ialign{$##$\cr
#1{\Leftarrow}\mkern-6mu\cleaders\hbox{$#1\mkern-2mu{=}\mkern-2mu$}\hfill
\mkern-6mu{\Rightarrow}\cr\noalign{\kern-.2326ex\nointerlineskip}\hfil\strut@#1#2\hfil\cr}}}
\def\Underrightarrow{\mathpalette\Underrightarrow@}
\def\Underrightarrow@#1#2{\vtop{\ialign{$##$\cr
\hfil\strut@#1#2\hfil\cr\noalign{\nointerlineskip}%
#1{=}\mkern-6mu\cleaders\hbox{$#1\mkern-2mu{=}\mkern-2mu$}\hfill
\mkern-6mu{\Rightarrow}\cr}}}
\let\Underarrow\Underrightarrow
\def\Underleftarrow{\mathpalette\Underleftarrow@}
\def\Underleftarrow@#1#2{\vtop{\ialign{$##$\cr
\hfil\strut@#1#2\hfil\cr\noalign{\nointerlineskip}#1{\Leftarrow}\mkern-6mu
\cleaders\hbox{$#1\mkern-2mu{=}\mkern-2mu$}\hfill
\mkern-6mu{=}\cr}}}
\def\Underleftrightarrow{\mathpalette\Underleftrightarrow@}
\def\Underleftrightarrow@#1#2{\vtop{\ialign{$##$\cr
\hfil\strut@#1#2\hfil\cr\noalign{\nointerlineskip}#1{\Leftarrow}\mkern-6mu
\cleaders\hbox{$#1\mkern-2mu{=}\mkern-2mu$}\hfill
\mkern-6mu{\Rightarrow}\cr}}}
\let\@@overline\overline
\def\Overline#1{\relax\ifmmode
\@@overline{\@@overline{#1}}\else $\@@overline{\@@overline{\hbox{#1}}}$\relax\fi}
\def\Underline#1{\relax\ifmmode
\@@underline{\@@underline{#1}}\else $\@@underline{\@@underline{\hbox{#1}}}$\relax\fi}
\def\Rightarrowfill{$\m@th\mathord=\mkern-6mu%
\cleaders\hbox{$\mkern-2mu\mathord=\mkern-2mu$}\hfill
\mkern-6mu\mathord\Rightarrow$}
\def\Leftarrowfill{$\m@th\mathord\Leftarrow\mkern-6mu%
\cleaders\hbox{$\mkern-2mu\mathord=\mkern-2mu$}\hfill
\mkern-6mu\mathord=$}
\def\leftrightarrowfill{$\m@th\mathord\leftarrow\mkern-6mu%
\cleaders\hbox{$\mkern-2mu\mathord-\mkern-2mu$}\hfill
\mkern-6mu\mathord\rightarrow$}
\def\Leftrightarrowfill{$\m@th\mathord\Leftarrow\mkern-6mu%
\cleaders\hbox{$\mkern-2mu\mathord=\mkern-2mu$}\hfill
\mkern-6mu\mathord\Rightarrow$}
\def\eqfill{$\m@th\mathord=\mkern-6mu%
\cleaders\hbox{$\mkern-2mu\mathord=\mkern-2mu$}\hfill
\mkern-6mu\mathord=$}
\let\doublefill\eqfill
\def\hrfill{$\m@th\mathord-\mkern-6mu%
\cleaders\hbox{$\mkern-2mu\mathord-\mkern-2mu$}\hfill
\mkern-6mu\mathord-$}
\def\triplefill{$\m@th\mathord\equiv\mkern-6mu%
\cleaders\hbox{$\mkern-2mu\mathord\equiv\mkern-2mu$}\hfill
\mkern-6mu\mathord\equiv$}
\def\downgroupfill{$\m@th\braceld\leaders\vrule\hfill\bracerd$}
\def\upgroupfill{$\m@th\bracelu\leaders\vrule\hfill\braceru$}
\def\overgroup#1{\mathop{\vbox{\ialign{##\crcr\noalign{\kern3\p@}
\downgroupfill\crcr\noalign{\kern3\p@\nointerlineskip}
$\hfil\displaystyle{#1}\hfil$\crcr}}}\limits}
\def\undergroup#1{\mathop{\vtop{\ialign{##\crcr
$\hfil\displaystyle{#1}\hfil$\crcr\noalign{\kern3\p@\nointerlineskip}
\upgroupfill\crcr\noalign{\kern3\p@}}}}\limits}
\def\downparenfill{$\m@th\braceld\leaders\vrule\hfill\bracerd$}
\def\upparenfill{$\m@th\bracelu\leaders\vrule\hfill\braceru$}
\def\overparen#1{\mathop{\vbox{\ialign{##\crcr\noalign{\kern3\p@}
\downparenfill\crcr\noalign{\kern3\p@\nointerlineskip}
$\hfil\displaystyle{#1}\hfil$\crcr}}}\limits}
\def\underparen#1{\mathop{\vtop{\ialign{##\crcr
$\hfil\displaystyle{#1}\hfil$\crcr\noalign{\kern3\p@\nointerlineskip}
\upparenfill\crcr\noalign{\kern3\p@}}}}\limits}
\newbox\@brackd \newbox\@bracku
\setbox\@brackd=\hbox {\vrule height 0pt depth
3pt width 1pt}\ht\@brackd=0pt\dp\@brackd=1pt
\setbox\@bracku=\hbox {\vrule height 3pt depth
0pt width 1pt}\ht\@bracku=1pt\dp\@bracku=0pt
\def\downbrackfill{$\m@th\copy\@brackd\leaders\vrule\hfill\copy\@brackd$}
\def\upbrackfill{$\m@th\copy\@bracku\leaders\vrule\hfill\copy\@bracku$}
\def\overbrack#1{\mathop{\vbox{\ialign{##\crcr\noalign{\kern3\p@}
\downbrackfill\crcr\noalign{\kern3\p@\nointerlineskip}
$\hfil\displaystyle{\kern1pt#1\kern1pt}\hfil$\crcr}}}\limits}
\def\underbrack#1{\mathop{\vtop{\ialign{##\crcr
$\hfil\displaystyle{\kern1pt#1\kern1pt}\hfil$\crcr\noalign
{\kern3\p@\nointerlineskip}
\upbrackfill\crcr\noalign{\kern3\p@}}}}\limits}
\def\updownbrackfill{$\m@th\copy\@bracku\kern-.8pt\leaders\vrule height 0.8pt
\hfill\kern-1pt\copy\@brackd$}
\def\downupbrackfill{$\m@th\copy\@brackd\kern-1pt\leaders\vrule height 0.8pt
\hfill\kern-1pt\copy\@bracku$}
\def\overbrackfillud#1{\mathop{\vbox{\ialign{##\crcr\noalign{\kern3\p@}
\updownbrackfill\crcr\noalign{\kern3\p@\nointerlineskip}
$\hfil\displaystyle{\kern1pt#1\kern1pt}\hfil$\crcr}}}\limits}
\def\underbrackfillud#1{\mathop{\vtop{\ialign{##\crcr
$\hfil\displaystyle{\kern1pt#1\kern1pt}\hfil$\crcr\noalign
{\kern3\p@\nointerlineskip}
\updownbrackfill\crcr\noalign{\kern3\p@}}}}\limits}
\def\overbrackfilldu#1{\mathop{\vbox{\ialign{##\crcr\noalign{\kern3\p@}
\downupbrackfill\crcr\noalign{\kern3\p@\nointerlineskip}
$\hfil\displaystyle{\kern1pt#1\kern1pt}\hfil$\crcr}}}\limits}
\def\underbrackfilldu#1{\mathop{\vtop{\ialign{##\crcr
$\hfil\displaystyle{\kern1pt#1\kern1pt}\hfil$\crcr\noalign
{\kern3\p@\nointerlineskip}
\downupbrackfill\crcr\noalign{\kern3\p@}}}}\limits}
\def\hdashfill{\leaders\hbox to 4pt{\hss\vrule height4.0pt depth-3.6pt
width2pt\hss}\hfill}
\def\vdashfill{{\leaders\vbox to 2.5pt{\vss\hrule
height1.25pt width.4pt\vss}\vfill}}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\def\overrightarrowfill#1{\mathop{\vbox{\ialign{##\crcr\noalign{\kern1\p@}
\rightarrowfill\crcr\noalign{\kern1\p@\nointerlineskip}
$\hfil\displaystyle{#1}\hfil$\crcr}}}\limits}
\def\underrightarrowfill#1{\mathop{\vtop{\ialign{##\crcr
$\hfil\displaystyle{#1}\hfil$\crcr\noalign{\kern1\p@\nointerlineskip}
\rightarrowfill\crcr\noalign{\kern1\p@}}}}\limits}
\def\overleftarrowfill#1{\mathop{\vbox{\ialign{##\crcr\noalign{\kern1\p@}
\leftarrowfill\crcr\noalign{\kern1\p@\nointerlineskip}
$\hfil\displaystyle{#1}\hfil$\crcr}}}\limits}
\def\underleftarrowfill#1{\mathop{\vtop{\ialign{##\crcr
$\hfil\displaystyle{#1}\hfil$\crcr\noalign{\kern1\p@\nointerlineskip}
\leftarrowfill\crcr\noalign{\kern1\p@}}}}\limits}
\def\overleftrightarrowfill#1{\mathop{\vbox{\ialign{##\crcr\noalign{\kern1\p@}
\leftrightarrowfill\crcr\noalign{\kern1\p@\nointerlineskip}
$\hfil\displaystyle{#1}\hfil$\crcr}}}\limits}
\def\underleftrightarrowfill#1{\mathop{\vtop{\ialign{##\crcr
$\hfil\displaystyle{#1}\hfil$\crcr\noalign{\kern1\p@\nointerlineskip}
\leftrightarrowfill\crcr\noalign{\kern1\p@}}}}\limits}
\def\Overrightarrowfill#1{\mathop{\vbox{\ialign{##\crcr\noalign{\kern1\p@}
\Rightarrowfill\crcr\noalign{\kern1\p@\nointerlineskip}
$\hfil\displaystyle{#1}\hfil$\crcr}}}\limits}
\def\Underrightarrowfill#1{\mathop{\vtop{\ialign{##\crcr
$\hfil\displaystyle{#1}\hfil$\crcr\noalign{\kern1\p@\nointerlineskip}
\Rightarrowfill\crcr\noalign{\kern1\p@}}}}\limits}
\def\Overleftarrowfill#1{\mathop{\vbox{\ialign{##\crcr\noalign{\kern1\p@}
\Leftarrowfill\crcr\noalign{\kern1\p@\nointerlineskip}
$\hfil\displaystyle{#1}\hfil$\crcr}}}\limits}
\def\Underleftarrowfill#1{\mathop{\vtop{\ialign{##\crcr
$\hfil\displaystyle{#1}\hfil$\crcr\noalign{\kern1\p@\nointerlineskip}
\Leftarrowfill\crcr\noalign{\kern1\p@}}}}\limits}
\def\Overleftrightarrowfill#1{\mathop{\vbox{\ialign{##\crcr\noalign{\kern1\p@}
\Leftrightarrowfill\crcr\noalign{\kern1\p@\nointerlineskip}
$\hfil\displaystyle{#1}\hfil$\crcr}}}\limits}
\def\Underleftrightarrowfill#1{\mathop{\vtop{\ialign{##\crcr
$\hfil\displaystyle{#1}\hfil$\crcr\noalign{\kern1\p@\nointerlineskip}
\Leftrightarrowfill\crcr\noalign{\kern1\p@}}}}\limits}
\let\@fill@loaded\triplefill
\else
\typeout{fill.sty already loaded}
\fi
\endinput
