Change footnote “numbering” temporarily

Question

I would like to change my footnote "numbering" style temporally to letters (a,b,c ...) the default numbering beeing numbers (1,2,3 ...).

This is needed only for specific paragraph, so I can't use the

\renewcommand{\thefootnote}{\alph{footnote}}

at the beginning of the document.

Answer 1

\newenvironment{alphafootnotes}
  {\par\edef\savedfootnotenumber{\number\value{footnote}}
   \renewcommand{\thefootnote}{\alph{footnote}}
   \setcounter{footnote}{0}}
  {\par\setcounter{footnote}{\savedfootnotenumber}}

\begin{document}
a\footnote{a} b\footnote{b}

\begin{alphafootnotes}
c\footnote{c} d\footnote{d}
\end{alphafootnotes}

e\footnote{e}
\end{document}

You'll get footnotes numbered 1, 2, a, b, 3.

You might also consider the packages manyfoot and bigfoot that provide multiple footnote schemes.

Answer 2

As @UlrichSchwarz mentioned, you need a counter to store the footnote counter. However, by renewing \thefootnote, you don't need to restore that if you place the entire paragraph within a group. This way TeX will automatically restore any changes that were made local to the group.

Here's an example:

\documentclass{article}
\newcounter{savefootnote}% Save footnote counter
\begin{document}
Here is a paragraph\footnote{My footnote}. Here is another sentence.

Here is a paragraph\footnote{My footnote}. Here is another sentence.

\begingroup
\setcounter{savefootnote}{\value{footnote}}% Store footnote counter
\setcounter{footnote}{0}% Reset footnote counter
\renewcommand{\thefootnote}{\alph{footnote}}% Modify footnote printing
Here is a paragraph\footnote{My footnote}. Here is another sentence.
\setcounter{footnote}{\value{savefootnote}}% Restore footnote counter
\endgroup

Here is a paragraph\footnote{My footnote}. Here is another sentence.

Here is a paragraph\footnote{My footnote}. Here is another sentence.

Here is a paragraph\footnote{My footnote}. Here is another sentence.

\end{document}
​

Of course, if you don't mind that the \alph footnote starts anywhere, then you don't even need to save the footnote counter in the first place.

Answer 3

I'm assuming you want to start the "temporary" footnote counter at zero (to get alphabetic "numbers" starting with "a", "b", ...) and, when the paragraph is completed, resume ordinary, i.e., arabic footnote numbering with the number you left off with before you switched temporarily to alphabetic footnote "numbering". If this understanding is correct, here's a solution:

... % text preceding the crucial paragraph(s)

\newcounter{tempfootnote}
\setcounter{tempfootnote}{\value{footnote}}
\setcounter{footnote}{0}
\renewcommand{\thefootnote}{\alph{footnote}}
... % text of the the crucial paragraph(s), including footnotes

\setcounter{footnote}{\value{tempfootnote}}
\renewcommand{\thefootnote}{\arabic{footnote}}
... % remainder of document, including footnotes

Note the blank lines, which serve to create paragraph breaks.