# Arrow with text above

I am drawing an arrow using the following command:
$\xleftarrow{\mbox{\tiny{BCast}}}$‎. I have tested the command in two different environments:

1. TeXShop (MacOS, uses TeX Live) outputs an arrow with the problem stated in the second item.
2. TeXmaker (Windows, uses MiKTeX) in a bidirectional environment (for writing Farsi) outputs the correct arrow with "Bcast" above it but the arrow seems to have splitted areas that are connected using dots.

Am I doing it wrong?
Edit: this is the "preview" rendering of the file under zoom of 1000x.

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I guess that the arrow only seems "to have splitted areas that are connected using dots". This comes from the definition of the extendible arrows. It's a previewer problem; in print you shouldn't see it. To check if it is a previewer problem, zoom in really deep, say with a magnification of 3000%, and see if it looks OK then.

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it can also be a problem of the used font. –  Herbert Dec 19 '10 at 9:20
I have not defined any specific font. Should I change the font for this specific command? –  Yasser Sobhdel Dec 19 '10 at 9:39
@Yasser: Could you please check if is it a previewer problem? I've updated my answer. –  Hendrik Vogt Dec 19 '10 at 10:37
Yes you are right. I am using the "preview" on mac and "Sumatra" on windows box. But when I used the "Adobe Acrobat 10" on Mac the arrow was smooth (I zoomed up to 6400). But the preview allows me to zoom up to 1000 and the picture in the edit section shows the problem. Thank you. –  Yasser Sobhdel Dec 19 '10 at 11:32

use package amsmath and then

$\xleftarrow{\text{BCast}}$‎


it recognises the current font setting. The arrow is a combination of arrow and a line and depending to the used font it may be nessesary to redefine the original arrow definition.

Herbert

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I am using the package. This didn't solve the problem. I still suffer from both problems in both environments. –  Yasser Sobhdel Dec 19 '10 at 8:10
then provide a complete example –  Herbert Dec 19 '10 at 8:37
I think there is no need to provide the full example because I am testing it on an empty document (just this single command along with document commands and usepackage command). In the edited version,I just omitted the Question mark problem because the TexShop after closing and reopening the document showed an extra question mark which is strange to me. So I thought this is the editor problem and removed that part. –  Yasser Sobhdel Dec 19 '10 at 9:09

I use a macro such as

\newcommand{\overlim}[1]{{\buildrel{#1}\over\longrightarrow\;}}


to type "whatever over a \longrightarrow". You might adapt something of this sort to your needs.

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Can you provide me with an example of text over this arrow? I did the same as \xleftarrow but the text is placed next to the arrow. –  Yasser Sobhdel Dec 19 '10 at 9:11
I use it in this way: \overlim{a.s} or \overlim{p} and the text comes out on top of the arrow. –  F. Tusell Dec 19 '10 at 9:23
The arrow does not stretch it self. Use a longer text, see if you get an arrow with as long as the width of the text? –  Yasser Sobhdel Dec 19 '10 at 9:38
No, it doesn't. I only use it with short text that has enough room over the regular \rightarrow (or \longrightarrow). I did not understand from your question that you wanted an stretchable arrow. For that you mighr try tou first build an arrow of the right size, then placing text atop it –  F. Tusell Dec 19 '10 at 18:02