Here is a proposal for a layout allowing to create algorithms more
friendly through lyx. Your comments and feelings on it are welcome. As I
really don't know latex, don't hesitate to make remarks and evolutions.
As attached file are:
1) article-algo.layout: the layout to install
2) algo.lyx: an example lyx file using the layout, and explaining how to
use it. Thus, before reading it, install the article-algo.layout and
reconfigure lyx.
BG.
#% Do not delete the line below; configure depends on this
# \DeclareLaTeXClass[article]{Article (algo)}
# Report textclass definition file. Taken from initial LyX source code
# Author : Matthias Ettrich <[EMAIL PROTECTED]>
# Transposed by Pascal André <[EMAIL PROTECTED]>
# Heavily modifed and enhanced by serveral developers.
# Input general definitions
Input stdclass.inc
# There are no chapters in an article.
NoStyle Chapter
NoStyle Chapter*
MaxCounter Counter_Section
SecNumDepth 3
TocDepth 3
# Change a bit Part and Part*
Style Part
Align Left
AlignPossible Left
TopSep 2
BottomSep 1.5
Font
Size Larger
EndFont
End
Style Part*
Align Left
AlignPossible Left
TopSep 2
BottomSep 1.5
Font
Size Larger
EndFont
End
# New style to write some algorithms
Style Algorithm
# Margin First_Dynamic
LatexType Item_Environment
LatexName algor
NextNoIndent 1
LeftMargin MM
LabelSep xxx
ItemSep 0
TopSep 0.5
BottomSep 0.5
ParSep 0
Align Block
AlignPossible Block, Left
LabelType Manual
LabelString MM
FreeSpacing 0
# standard font definition
Font
Family Typewriter
EndFont
# label font definition
LabelFont
Series Bold
EndFont
Preamble
%% Needed packages
\usepackage{algorithm}
\usepackage{algorithmic}
%% Default screen keywords definition
\newcommand{\keyif}{if}
\newcommand{\keyelseif}{elseif}
\newcommand{\keyelse}{else}
\newcommand{\keyendif}{endif}
\newcommand{\keyfor}{for}
\newcommand{\keywhile}{while}
\newcommand{\keyrepeat}{repeat}
\newcommand{\keyuntil}{until}
\newcommand{\keyendfor}{endfor}
\newcommand{\keyendwhile}{endwhile}
%% Two arguments needed
%%
\def\mytalg[#1](#2){%
\let\item=\stditem
\ifthenelse{\equal{#1}{\keyif}}{\IF{#2}}{%
\ifthenelse{\equal{#1}{\keyelseif}}{\ELSIF{#2}}{%
\ifthenelse{\equal{#1}{\keyfor}}{\FOR{#2}}{%
\ifthenelse{\equal{#1}{\keywhile}}{\WHILE{#2}}{%
\ifthenelse{\equal{#1}{\keyuntil}}{\UNTIL{#2}}{%
\STATE #1(#2)}}}}}
\let\item=\myalg
}
%% Only one real argument used
%%
\def\myoalg[#1]#2{%
\let\item=\stditem
\ifthenelse{\equal{#1}{\keyelse}}{\ELSE}{%
\ifthenelse{\equal{#1}{\keyendif}}{\ENDIF}{%
\ifthenelse{\equal{#1}{\keyendfor}}{\ENDFOR}{%
\ifthenelse{\equal{#1}{\keyendwhile}}{\ENDWHILE}{%
\ifthenelse{\equal{#1}{\keyrepeat}}{\REPEAT}{%
\STATE }}}}}
\let\item=\myalg
}
%% Main command
%%
\def\myalg[#1]{%
\@ifnextchar({\mytalg[#1]}{%
\@ifnextchar~{\myoalg[#1]}{\myoalg[#1]{ }}}
}
\newenvironment{algor}
{
\@ifundefined{stditem}{%
\begin{algorithmic}
\let\stditem=\item
\let\item=\myalg
\newcounter{algcount}
\setcounter{algcount}{1}
}{%
\addtocounter{algcount}\@ne
}
}{
\addtocounter{algcount}\m@ne
\ifnum \value{algcount}=0
\let\item=\stditem
\end{algorithmic}
\fi
}
EndPreamble
End
#LyX 1.1 created this file. For more info see http://www.lyx.org/
\lyxformat 2.15
\textclass article-algo
\language default
\inputencoding latin1
\fontscheme default
\graphics default
\paperfontsize default
\spacing single
\papersize Default
\paperpackage a4
\use_geometry 0
\use_amsmath 0
\paperorientation portrait
\secnumdepth 3
\tocdepth 3
\paragraph_separation indent
\defskip medskip
\quotes_language english
\quotes_times 2
\papercolumns 1
\papersides 1
\paperpagestyle default
\layout Title
Proposal for a LyX Algorithm Style
\layout Date
17 september 2000
\layout Standard
\begin_inset LatexCommand \tableofcontents{}
\end_inset
\layout Section
Introduction
\layout Standard
This file is an example file using a customised layout that allows to write
algorithms without using any LaTeX command in a lyx document.
The layout is built in order to fulfill the WYSIWYM principles.
\layout Section
Document class
\layout Standard
When
\family typewriter
article-algo.layout
\family default
is installed (in the
\family typewriter
~/.lyx/layout
\family default
directory), and lyx is reconfigured, the
\family typewriter
Article
\protected_separator
(algo)
\family default
class should be available.
This is the current class of this document.
\layout Section
Using the
\family typewriter
Algorithm
\family default
style
\layout Standard
To use the lyx algorithm style, simply select the
\family typewriter
Algorithm
\family default
style, and respect the following rules:
\layout Itemize
The style is derived from the Enumerate style, and thus the first word of
each item has a special meaning.
The first word you write (bold typed) must be one of the predefined algorithmic
keywords (if, else, etc.).
\layout Itemize
If the first word is not recognised as a predefined keyword, then it is
assimilated to the algorithmic environment
\backslash
STATE keyword.
\layout Itemize
For the keywords that need extra parameters (such as: if, else
\protected_separator
if, until, while), these parameters must be between parentheses.
\layout Itemize
If the item levels are used (only for screen viewing purpose), they must
be consistent, i.e.
at the end of the algorithm, the deep level must come to zero.
\layout Standard
The screen viewing of the written algorithm can be customised as follow:
\layout Itemize
Use the item levels to indent the algorithm blocks.
Besides the screen aspect, the item levels are not used.
\layout Itemize
Customise the algorithm keywords with your own language keywords (see
\begin_inset LatexCommand \ref{sec:screen-keys}
\end_inset
).
\layout Standard
The algorithms
\begin_inset LatexCommand \ref{alg:small-example}
\end_inset
and
\begin_inset LatexCommand \ref{alg:big-example}
\end_inset
are two examples, in which the
\backslash
STATE items are defined with
\begin_inset Quotes eld
\end_inset
-
\begin_inset Quotes eld
\end_inset
as first word.
\layout Standard
\begin_float alg
\layout Algorithm
if (something is true)
\layout Algorithm
- do action 1
\layout Algorithm
- do action 2
\layout Algorithm
elseif (something else is true)
\layout Algorithm
- perform the specific action
\layout Algorithm
repeat
\layout Algorithm
- run action 3
\layout Algorithm
until (everything is done)
\layout Algorithm
endif
\layout Caption
\begin_inset LatexCommand \label{alg:small-example}
\end_inset
Example without (screen) indentation
\end_float
\layout Standard
\begin_float alg
\layout Algorithm
if (something is true)
\begin_deeper
\layout Algorithm
- do action 1
\layout Algorithm
- do action 2
\end_deeper
\layout Algorithm
elseif (something else is true)
\begin_deeper
\layout Algorithm
- perform the specific action
\layout Algorithm
repeat
\begin_deeper
\layout Algorithm
- run action 3
\end_deeper
\layout Algorithm
until (everything is done)
\end_deeper
\layout Algorithm
else
\begin_deeper
\layout Algorithm
- do action 4
\layout Algorithm
if (another thing is true)
\begin_deeper
\layout Algorithm
for (
\begin_inset Formula \( i=0;\, i<10;\, i++ \)
\end_inset
)
\begin_deeper
\layout Algorithm
- process the iteration
\end_deeper
\layout Algorithm
endfor
\layout Algorithm
while (it stills true)
\begin_deeper
\layout Algorithm
- run action 5
\end_deeper
\layout Algorithm
endwhile
\end_deeper
\layout Algorithm
endif
\end_deeper
\layout Algorithm
endif
\layout Caption
\begin_inset LatexCommand \label{alg:big-example}
\end_inset
Example with (screen) indentation
\end_float
\layout Section
Customisation
\layout Standard
The lyx algorithm style can be used in any language, by redefining the following
macro commands in the latex preamble:
\layout Subsection
\begin_inset LatexCommand \label{sec:screen-keys}
\end_inset
Screen keywords
\layout Standard
It deals with the words written in the lyx document, and that appears on
the screen.
In the document, the tokens that define
\backslash
IF,
\backslash
ELSE, etc.
used in the algorithms are
\begin_inset Quotes eld
\end_inset
if
\begin_inset Quotes erd
\end_inset
,
\begin_inset Quotes eld
\end_inset
else
\begin_inset Quotes erd
\end_inset
, etc.
These are redefinable macros.
Their default definitions are:
\layout LyX-Code
\backslash
newcommand{
\backslash
keyif}{if}
\layout LyX-Code
\backslash
newcommand{
\backslash
keyelseif}{elseif}
\layout LyX-Code
\backslash
newcommand{
\backslash
keyelse}{else}
\layout LyX-Code
\backslash
newcommand{
\backslash
keyendif}{endif}
\layout LyX-Code
\backslash
newcommand{
\backslash
keyfor}{for}
\layout LyX-Code
\backslash
newcommand{
\backslash
keywhile}{while}
\layout LyX-Code
\backslash
newcommand{
\backslash
keyrepeat}{repeat}
\layout LyX-Code
\backslash
newcommand{
\backslash
keyuntil}{until}
\layout LyX-Code
\backslash
newcommand{
\backslash
keyendfor}{endfor}
\layout LyX-Code
\backslash
newcommand{
\backslash
keyendwhile}{endwhile}
\layout Subsection
Output keywords
\layout Standard
To customise the algorithm words in the output, redefine the algorithmic
environment macros.
The default definitions of these macros are:
\layout LyX-Code
\backslash
newcommand{
\backslash
algorithmicrequire}{
\backslash
textbf{Require:}}
\layout LyX-Code
\backslash
newcommand{
\backslash
algorithmicensure}{
\backslash
textbf{Ensure:}}
\layout LyX-Code
\backslash
newcommand{
\backslash
algorithmiccomment}[1]{
\backslash
{#1
\backslash
}}
\layout LyX-Code
\backslash
newcommand{
\backslash
algorithmicend}{
\backslash
textbf{end}}
\layout LyX-Code
\backslash
newcommand{
\backslash
algorithmicif}{
\backslash
textbf{if}}
\layout LyX-Code
\backslash
newcommand{
\backslash
algorithmicthen}{
\backslash
textbf{then}}
\layout LyX-Code
\backslash
newcommand{
\backslash
algorithmicelse}{
\backslash
textbf{else}}
\layout LyX-Code
\backslash
newcommand{
\backslash
algorithmicelsif}{
\backslash
algorithmicelse
\backslash
\backslash
algorithmicif}
\layout LyX-Code
\backslash
newcommand{
\backslash
algorithmicendif}{
\backslash
algorithmicend
\backslash
\backslash
algorithmicif}
\layout LyX-Code
\backslash
newcommand{
\backslash
algorithmicfor}{
\backslash
textbf{for}}
\layout LyX-Code
\backslash
newcommand{
\backslash
algorithmicforall}{
\backslash
textbf{for all}}
\layout LyX-Code
\backslash
newcommand{
\backslash
algorithmicdo}{
\backslash
textbf{do}}
\layout LyX-Code
\backslash
newcommand{
\backslash
algorithmicendfor}{
\backslash
algorithmicend
\backslash
\backslash
algorithmicfor}
\layout LyX-Code
\backslash
newcommand{
\backslash
algorithmicwhile}{
\backslash
textbf{while}}
\layout LyX-Code
\backslash
newcommand{
\backslash
algorithmicendwhile}{
\backslash
algorithmicend
\backslash
\backslash
algorithmicwhile}
\layout LyX-Code
\backslash
newcommand{
\backslash
algorithmicloop}{
\backslash
textbf{loop}}
\layout LyX-Code
\backslash
newcommand{
\backslash
algorithmicendloop}{
\backslash
algorithmicend
\backslash
\backslash
algorithmicloop}
\layout LyX-Code
\backslash
newcommand{
\backslash
algorithmicrepeat}{
\backslash
textbf{repeat}}
\layout LyX-Code
\backslash
newcommand{
\backslash
algorithmicuntil}{
\backslash
textbf{until}}
\layout Section
Limitations
\layout Standard
This lyx algorithm style has (at least) the following limitations:
\layout Itemize
Its behaviour is not robust, and errors can appears silently.
\layout Itemize
The use of double-parentheses for extra parameters (e.g: if ((something is
true)) ) does not work fine.
\layout Itemize
All the algorithmic package specific words are not supported (e.g: require,
ensure, etc.).
\the_end
