[Tex/LaTex] Latex enumerate environment I want to enumerate with A.1,A.2,…,A.n. How does one do this

#enumeratelists

I am using latex to type up a logical system that has some equations. The abbreviation for the logical system is DAS. I would like the equations to be numbered
DAS.1
DAS.2
…
DAS.n

I expected that

\begin{enumerate}[{DAS.1}]
    \item
    \item
    ...
   \item
\end{enumerate}

would work. However the output I get is:

D1S.1
D2S.2
…
DnS.n

So I suppose the question could be restated as: how does one control which letter the enumerate environment … enumerates? Any suggestions are greatly appreciated.

Best Answer

The enumerate package provides the optional argument functionality to listing environments like enumerate. However, to make this work as expected, you need to "shield" the unwanted enumeration from the choices. This is done by putting DAS inside braces, and therefore using

\begin{enumerate}[{DAS}.1]

since in

\begin{enumerate}[{DAS.1}]

the first available enumerations (albeit grouped) are specified by A and 1, causing the D1S.1, D2S.2, ... output. That is, enumerate identifies two locations to place the enumeration, and sets the enumeration style as the last one encountered (1/\arabic in this case). Consequently, using

\begin{enumerate}[{DAa1S.1}]

would yield the enumeration D111S.1, D222S.2, ..., as is visible from the following minimal example:

enter image description here

\documentclass{article}
\usepackage{enumerate}% http://ctan.org/pkg/enumerate
\begin{document}
\begin{enumerate}[{DAS}.1]
  \item stuff
  \item stuff
  \item stuff
\end{enumerate}
\begin{enumerate}[{DAa1S.1}]
  \item stuff
  \item stuff
  \item stuff
\end{enumerate}
\end{document}

Related Solutions

[Tex/LaTex] Best Practices for Using Enumerations Within Theorem Environments

I would define the items using the functionality of the enumitem package. This would require you to label the items that you want to reference (using \label) and reference them accordingly using \ref.

In the minimal example below the list of equivalent items are constructed using a label that is formatted as (<arabic#>) with an equivalent referencing output. This is done using the optional arguments to the enumerate environment ([label=..,ref=..]). The command \Implies{<ref1>}{<ref2>} constructs $\text{\ref{<ref1>}}\implies\text{\ref{<ref2>}}$ , for consistency and ease-of-use.

enter image description here

\documentclass{article}
\usepackage{enumitem}% http://ctan.org/pkg/enumitem
\usepackage{amsthm}% http://ctan.org/pkg/amsthm
\usepackage{amsmath}% http://ctan.org/pkg/amsmath
\newtheorem{theorem}{Theorem}
\newcommand{\Implies}[2]{$\text{\ref{#1}}\implies\text{\ref{#2}}$}% X => Y
\begin{document}
\begin{theorem}
The following are equivalent:
  \begin{enumerate}[label=(\arabic*),ref=(\arabic*)]
   \item Statement 1 \label{statement1}
   \item Statement 2 \label{statement2}
   \item Statement 3 \label{statement3}
  \end{enumerate}
\end{theorem}

\begin{proof}
\Implies{statement1}{statement2}: Proof if~\ref{statement1} then~\ref{statement2}.
\Implies{statement2}{statement3}: Proof if~\ref{statement2} then~\ref{statement3}.
\Implies{statement3}{statement1}: Proof if~\ref{statement3} then~\ref{statement1}.
\end{proof}
\end{document}

The main approach here is to allow referencing of listed items so you don't have to worry about whether you're changing the appearance and have to subsequently modify your (hard-)coded proof. Additionally, you only need to label those entries you would be referencing. In this case, all statements were labelled.

[Tex/LaTex] How to remove unnecessary space in flalign* environment

Here is some lazy way:

\documentclass{article}
\date{}
\usepackage{amsmath}
\usepackage{amssymb}
\usepackage{graphicx}
\usepackage{tikz}
\addtolength{\oddsidemargin}{-.875in}
\addtolength{\evensidemargin}{-.875in}
\addtolength{\textwidth}{1.75in}
\addtolength{\topmargin}{-.875in}
\addtolength{\textheight}{1.75in}


\begin{document}
\textbf{Question 3.6.}
\begin{enumerate}
\setlength\abovedisplayskip{0pt}           %% new
\item $\mathcal{P}(\emptyset)=\{\emptyset\}$
\item \begin{minipage}[t]{\linewidth}      %% new
\vspace{-\baselineskip}
 \begin{flalign*}
\mathcal{P}\Big(\mathcal{P}\big(\mathcal{P}(\emptyset)\big)\Big)&=\mathcal{P}\Big(\mathcal{P}\big(\{\emptyset\}\big)\Big)&\\
\mathcal{P}\big(\{\emptyset\}\big)&=\big\{\emptyset ,\{\emptyset\}\big\}\\
\mathcal{P}\Big(\mathcal{P}\big(\mathcal{P}(\emptyset)\big)\Big)&=\mathcal{P}\big(\big\{\emptyset ,\{\emptyset\}\big\}\big)\\
&=\Big\{\emptyset , \{\emptyset\},\big\{\{\emptyset\}\big\}, \big\{\emptyset ,\{\emptyset\}\big\}\Big\}
\end{flalign*}
\end{minipage}                            %% new
\end{enumerate}
\end{document}

enter image description here

Best Answer

Related Solutions

[Tex/LaTex] Best Practices for Using Enumerations Within Theorem Environments

[Tex/LaTex] How to remove unnecessary space in flalign* environment

Related Question