LaTeX notes

LaTeX WIKI Books

LaTeX/Macros

There are situations where LaTeX does not provide a command or environment that matches your needs, or the output of produced by some existing command may not meet your requirements. When this happens, we can teach LaTeX new tricks:

New Commands

To add your own command, use

name is the new command name, note that name can not contain digits. num specifies the number of arguments the new command takes (up to 9). If missing it defaults to 0, i.e. no argument allowed. definition is the text to be replaced. A simple tex replacement:

Commands take arguments:

Note that there is no overriding function in LaTeX, so you have to give them different names even when two commands only differ in the number of arguments.

Use \renewcommand to explicityl overwrite an existing command. Use \providecommand to let LaTeX silently ignore the new command if the command is already defined.

If you want a default parameter for \newcommand, use the form

This will make first argument optional, and if not specified, use the value default. For example:

Some commands are fragile, that is they fail in some environments. If a macro works in body text but not (for example) in a figure caption, then replace the \newcommand{\MyCommand} with \DeclareRobustCommand{\MyCommand} in the preamble. This is especially true for macros which, when expanded, produce text that is written to a .aux file.

Package General Info

How to find documentation for a specific package

texdoc <package-name>

Specific Package Notes

algorithms Bundle [2009-08-24 Mon] `algorithm` and `algorithmic`

Note that algorithms is a bundle which provide algorithm and algorithmic package, you should use \usepackage{algorithm} or \usepackage{algorithmic} instead of \usepackage{algorithms}.

This package provides two environments, algorithmic and algorithm, which are designed to be used together but may be used saparately depending on the necessities of the user. The algorithmic environment provides an environment for describing algorithms and the algorithm environment provids a "float" wrapper for algorithms (implemented using algorithmic or some other methdo at the user's option).

The `algorithmic` package

This package provides a number of commands for typesettings popular algorithmic constructus.

Simple Statement
if-then-else

In the third forms there is no limit placed on the number of \ELSIF that may be used.
for loop

You can use \TO connective for distinct to text.
while loop
repeat-until loop
Infinit loop
Logic connectives

We have \AND, \OR, \XOR, \NOT.
Precondition
Postcondition
Returning Values

True and false values: \TRUE and \FALSE.
Printing messages
Comments

For comments on the same line with \IF etc. constructs, use the optional argument.