# Replace the $$…$$ macro with the $…$ macros? - Prefer the way LaTeX lays it out, but $ are faster to write Is there a way to replace the $$...$$ macro with the $...$ macros? (and replace inline mathmode as well) I realised the only way I can write the \sum_{i=1}^{10} t_i is between the $...$ LaTeX maths-mode. It also seems to layout the maths nicer (bigger, with gaps). However, $$...$$ is faster to write... so is there a way to replace the $$...$$ macro, to act in the LaTeX fashion? - Nah, read that that mode isn't supported properly by LaTeX (ref: WikiBooks) – A T Oct 6 '11 at 0:49 Caramdir: Well whichever is the one for inline want to replace$, and for newline replace $$– A T Oct 6 '11 at 0:50 I don't think this is possible, since $...$ themselves are defined in terms of $$. Or am I wrong? – Werner Oct 6 '11 at 1:46
You could use LuaTeX to write an "input transformation" to turn $$ into $ and $. – topskip Oct 6 '11 at 5:56 Textmate's LaTeX mode turns $$[tab] into $ <cursor> $. – topskip Oct 6 '11 at 5:56

This is not a direct answer to your question but maybe a better solution: use snippet management to ease writing $...$ constructions. This of course requires an editor with support for snippets management.
You could create a snippet that activates when writing Tab (or some key command) and when it's activates it inputs   and places the cursor between them. In many snippets managers this snippet is simply: $1$  For an explanation of how YASnippet, a snippet manager for Emacs, works, see Working with templates. - That is what Textmate does (with -tab). I'd accept that answer if I had asked that question :) – topskip Oct 6 '11 at 6:17 Since you are at it, replace it not with $...$ but with \begin{align*}...\end{align*}. It should be functionally equivalent, easier to read and transform into something else (want numbering? Remove the *. Want to display two equations side-by-side? Just do it!) – Federico Poloni Oct 6 '11 at 7:11 I use TeXWorks. Is there a feature like this for it? – A T Oct 6 '11 at 15:19 @AT Dunno. Maybe that is for another question. – N.N. Oct 6 '11 at 15:22 N.N: Could you please illustrate a MWE if possible? Maybe rendering $...$ from typing  and automatically placing the cursor ready for typing inside the $cursor$ mode. – night owl Oct 9 '11 at 10:08 Personally, I think that you should just get into the habit of typing $ and $ as quickly as possible and I think that you'll find that you soon develop the right "muscle memory" that it becomes as fast as typing $$. But if you want to do a one shot conversion, then I have a script that might help you. I wrote it a while ago, probably when I was in a similar circumstance (the details are hazy in my memory) and wanted to convert my old files. I still use it when I get sent something by a collaborator or student that uses $$. You can find it from my website, at http://www.math.ntnu.no/~stacey/HowDidIDoThat/LaTeX/debuck.html (The name is from the American word "buck" for "dollar".) - No it is not possible to redefine them the way you want. However, if you write your maths correctly you can use either of them without any problem. Consider this code: \documentclass{article} \begin{document} \fbox{ \begin{minipage}{5cm} This is a test $$\sum_{i=1}^{10} t_i$$ and $$\sum_{i=1}^{10} t_i$$ and another \end{minipage}} \fbox{ \begin{minipage}{5cm} This is a test $\sum_{i=1}^{10} t_i$ and $\sum_{i=1}^{10} t_i$ and another \end{minipage}} %% This will make a slightly different layout \fbox{ \begin{minipage}[t]{5cm} This is a test $$\sum_{i=1}^{10} t_i$$ and $$\sum_{i=1}^{10} t_i$$ and another \end{minipage}} \fbox{ \begin{minipage}[t]{5cm} This is a test $\sum_{i=1}^{10} t_i$ and $\sum_{i=1}^{10} t_i$ and another \end{minipage}} \fbox{ \begin{minipage}{5cm} This is a test \math x=y+5 \endmath\ and \ldots This is a test x=y+5$and \ldots This is a test $$x=y+5$$ and \ldots \end{minipage}} \end{document}  The first two boxes are identical, as they have been written correctly as a single paragraph. The second one the LaTeX way, as you observed in your question is a bit "loose". If you are aware of these differences you can use $$ without any issues. For inline math I always use  and so far it hasn't caused the universe to collapse into a black hole! Caveat: If you use any maths packages or amsmath you will be well advised to rather stay with $..$, although for the example above just using usepackage{amsmath} will provide consistent results for both cases, but will fail if you use the option fleqn. See also Is  ...  okay to use, while $$ ... $$ is not recommended? and Why is $...$ preferable to$$?. - Every guide I've seen has said to avoid $$...$$ due to a variety of issues, yet$...$doesn't seem to be mentioned as much. ctan.org/pkg/l2tabu-english for example. Are you going to break packages like the AMS ones by using the plain-tex math mode? – Canageek Oct 6 '11 at 2:13 @Canageek You cannot break a package by using it, but you run the risk of inconsistent spacing. In my first example everything is one paragraph and hence there are no issues. – Yiannis Lazarides Oct 6 '11 at 2:21 @Canageek: You will certainly break parts of of amsmath like fleqn. You will also probably break some packages that modify math-mode layout (like breqn). \qedhere in equations will also stop working correctly. So I guess you should only use $\$ if you really know what you are doing. – Caramdir Oct 6 '11 at 2:22