alignmacrosmath-mode
I would like to define
$$$ \zeta(s) = \dfrac1{1^s} + \dfrac1{2^s} + \cdots $$$
as a short hand for
\begin{align}
\zeta(s) = \dfrac1{1^s} + \dfrac1{2^s} + \cdots
\end{align}`
How should I go about doing this?
PS: I am aware of using newcommand to define something like
\newcommand{\ba}[1]{\begin{align}#1 \end{align}}
You may want to take a look at easybmat:
\documentclass{article}
\usepackage{easybmat}
%\usepackage{etex} % if you also want tikz, then you also need etex,
%\usepackage{tikz} % and they have to be loaded AFTER easybmat
\newenvironment{bvec}[1]{\begin{BMAT}(r)[0pt]{c}{#1}}{\end{BMAT}}
\newenvironment{pbvec}[1]{\left(\begin{bvec}{#1}}{\end{bvec}\right)}
\begin{document}
$span \{
\begin{pbvec}{ccccc} 1 \\ \vdots \\ \vdots \\ 1 \\ 1 \end{pbvec},
\begin{pbvec}{ccccc} 0 \\ 1 \\ \vdots \\ \vdots \\ 1 \end{pbvec},
\begin{pbvec}{ccccc} 0 \\ 0 \\ 1 \\ \vdots \\ 1 \end{pbvec}
\begin{bvec}{ccccc} \cdots \\ {} \\ \ddots \\ \ddots \\ \cdots \end{bvec}
\begin{pbvec}{ccccc} 0 \\ \vdots \\ \vdots \\ 0 \\ 1 \end{pbvec}
\}$
\end{document}
which results in
There are a few annoying things with BMAT:
{} in the fourth line).The first problem you have is that you cannot create a macro starting with \end... when using \newcommand. This check is defined inside the LaTeX kernel as part of an \@ifdefinable condition. To circumvent this you need to use TeX directives. That is,
\def\endexer#1{<stuff>}
rather than
\newcommand{\endexer}[1]{<stuff>}
Secondly, the \newcommand syntax has the following structure (see source2e.pdf):
\newcommand*{\foo}[<i>][<j>]{<text>}
* is optional\foo is the command to be created<i> is the number of arguments to gobble (up to 9); this references mandatory or a possible optional argument<j> is the default value of the first optional argument (if it exists does not exist); can only have one<text> is the macro definition when using \fooFor \newcommand{\foo}[1]{stuff #1} you would use it as \foo{<stuff>}, not \foo[<stuff>]. This latter usage would have required a definition of \foo of the form
\newcommand{\foo}[1][]{<stuff>}
Note the second set of [], denoting that \foo takes an optional argument (that is empty by default/if not specified).
Specific to your case, use \endexer{123}, not \endexer[123].
Here is a minimal example:
\documentclass{article}
\usepackage{hyperref}
\newcommand{\qqq}{\section{Question}\begin{enumerate}}
\newcommand{\exer}{\end{enumerate}\section{Exercises}\begin{enumerate}}
\def\endexer#1{\end{enumerate}\href{my.url.com/path/{#1}}{Take the quiz}}
\begin{document}
\qqq
\item What is $2+3$?
\exer
\item Write a program to compute $2+3$.
\endexer{123}
\end{document}
Best Answer
You can. But I strongly discourage you to use the following code that implements your idea. The resulting document code is obscure and error prone. If you forget a
$somewhere, you'll probably get weird error messages when TeX is very far from the point where the missing$should be.Disclaimer. Using this code can cause kittens die; it can also cause the computer to rebel against you and create a computer domination over the world. You've been advised.
For example, forgetting the
$afterabc, you get an error at line 34, which readsTry it. Then forget about this idea. Using
\newcommand{\ba}[1]{\begin{align}#1\end{align}}is even worse.