Making Math Look Pretty – or How to Use LaTeX

Making Math Look Pretty – or How to Use LaTeX Kristi Meyer Iowa State University kristi@iastate.edu

Basics of LaTeX • A computer program for typesetting text and mathematical formulas • Uses commands to create mathematical symbols • Not a WYSIWYG program • Need to compile the file in order to see the finished product

Basics of LaTeX – Commands • Always begin with a backslash \ • Case sensitive • Consist of letters only • Some have parameters • Square brackets [ ] after the command name are for optional parameters • Curly braces { } after the command name are for required parameters

Getting Started • Can use lots of different programs to create a LaTeX file • All computers here use WinEdt • Need to begin by creating a new file

Input File Structure • Begins with a preamble • \documentclass[options]{class} • class specifies the type of document to be created • Usually use article or amsart • Can also use slides or siamltex • options customizes the document class you are using • Can be used to set font size (10, 11, or 12 pt), set paper size, use one or two columns, etc. • See Getting Started with LaTeX, pgs. 12 – 13, for more information

Input File Structure • Begins with a preamble • \usepackage{package} • Packages add new features and commands to LaTeX • Common packages: amsmath, amssymb, graphics • Can also define new commands in the preamble, specify page numbering, etc.

Input File Structure • Now we’re ready to begin the body of the text • \begin{document} • \begin{…} commands always need to be followed (eventually) by \end{…} commands • Enter the actual content here • \end{document}

Typesetting Your Document • Click the “LaTeX” or “PDF LaTeX” button on the top right • To view your file, click “DVI” or the Adobe Acrobat symbol • DVI stands for “device independent” – it’s basically a generic viewer • Can change between DVI, PDF, or PS files • Document is automatically saved when you typeset it

Types of LaTeX Files • .tex – input file, needs to be compiled • .dvi – DVI file, shows what your file looks like • .tex.bak – backup LaTeX file, is changed when document is typeset • .log – log file, tells what happened the last time you compiled your document • Helpful to look at if there are errors and you don’t know why

Sections of a Paper • \title[label]{actual title} • If you label your title, you’ll be able to reference it later • Can also label theorems, equations, figures, tables, etc. • \author{authors} • Need to put \maketitle after title and authors • \today • Gives the current date • Usually want this centered

Sections of a Paper • \thanks{…} • Creates a footnote with whatever is in the braces • Usually used after authors’ names for academic information • Abstract • Use \begin{abstract} and \end{abstract} • Keywords • Use \begin{keywords} and \end{keywords} • OR use \keywords{…}

Sections of a Paper • Papers should be divided into sections, subsections, etc. • Important commands: • \section{Title of section} • \subsection{…} • \subsubsection{…} • \paragraph{…} • \subparagraph{…}

Sections of a Paper • Bibliography • \begin{thebibliography}{number} and \end{thebibliography} • number is 9, 99, 999, etc. • Tells LaTeX how if you will be using only single-digit numbers, double-digit numbers, etc. • Use \bibitem{label} to create a new reference • label lets you reference that item elsewhere in the paper

Referencing Using Labels • May want to reference a section, theorem, figure, example, etc. somewhere else in the document • To label a section: • \section{Title}\label{Label for section} • To reference a section: • \ref{Label for section} • Only gives the section number – you’ll need to type Section separately

Theorems and Definitions • Can decide what style you want your theorems, definitions, corollaries, etc. • Two possibilities for numbering: • Theorem 1, Example 1, Theorem 2, Lemma 1, etc. • \theoremstyle{…} • \newtheorem{short name}{long name} • Short name is what you type • Long name is what is displayed on the page

Theorems and Definitions • Two possibilities for numbering: • Theorem 1, Example 2, Lemma 3, Example 4, etc. • \newtheorem{shortname}[style]{longname} • For unnumbered theorems, use either command with \newtheorem* • * can be used in many environments for unnumbered items • May need to include the package amsthm in order to properly display theorems

Environments • Many environments available in TeX • Used to help format parts of your document • Always need \begin{environment name} and \end{environment name}

Environments • Itemize environment • \begin{itemize} and \end{itemize} • Creates an outline using bullet points • Items within the section are created by \item • Can nest itemize environments within one another

Environments • Enumerate environment • \begin{enumerate} and \end{enumerate} • Creates an outline using numbers and letters • Items within the section are created by \item • Can nest enumerate environments within one another • Centered environment • \begin{center} and \end{center} • To end a line, use \\

Typesetting Math • Mathematical text is placed between $ • Math mode is normally displayed inline • Can make some expressions look funny • To display math mode in a larger font, use \displaystyle • Makes all symbols within $ larger • For text within math mode, use \text{…} • Math mode uses italics and no spaces between words

Useful Mathematical Commands • Greek letters • $\pi$ for lowercase, $\Pi$ for uppercase • No command for $\Alpha$ - just use A • Fractions • $\frac{numerator}{denominator}$ • For a larger fraction, use \displaystyle

Useful Mathematical Commands • Superscripts and Subscripts • $x^2$ • $x_2$ • Use curly braces to group items together • $x_{i_2}$ or $x_{min}$ • Can have a superscript and a subscript on the same character • $x_i^3$

Useful Mathematical Commands • Limits and Integrals • Probably want to use \displaystyle, otherwise they’ll look funny • $\displaystyle \lim_{x \to \infty} 3x$ • $\displaystyle \int_0^2 x\ dx$ • The \ gives a space between x and dx • Lots more commands on pgs. 58 – 65 of Getting Started with LaTeX

Other Important Characters • Quote marks • For left-hand quote marks, use `` • For right-hand quote marks, use ” or ’’ • Comments • Can comment out sections of file • Allows you to not display text without deleting it • Use % at the beginning of any lines you want to comment out

Defining New Commands • Typing some long commands over and over is not fun • Can define a new command that’s easier to type • Goes in preamble • \newcommand{newname}{oldname} • newname cannot be the name of an existing command

Mathematical Environments • Equation environment • \begin{equation} and \end{equation} • Automatically numbers equations • For no numbers, use equation* • Can label equations by \label{name} • Centers equation on page • Do not need $ within equation environment

Mathematical Environments • Align environment • \begin{align} and \end{align} • For no numbers, use align* • Put & in front of the symbol in each line that you want aligned • End each line (except the last one) with \\ • Do not need $ within align environment • Proof environment • \begin{proof} and \end{proof}

Arrays • Especially used for matrices • Begin with left symbol for matrix • $\left[ • Next, begin array environment • \begin{array}{lrc} • Tells how many columns you have and their alignment

Arrays • Specify the entries of the matrix • Separate the entries by & • End each row (except the last one) by \\ • End the array • \end{array} • Create the right side symbol for the matrix • \right]$

Arrays • Can also have lines within arrays • Horizontal lines • Use \hline after each row that you want a line under • x^2 & 4x & 3 \\ \hline • Vertical lines • Put | between the columns that you want lines between • \begin{array}{lr|c}

Tables • Basically the same as arrays • \begin{tabular}{lrc} and \end{tabular} • Can add lines in the same way that you do for arrays

Figures • Often used to import some other type of file (usually a .ps file) into your document • Can generate graphics in LaTeX, but this is harder to do • Any imported file needs to be in the same directory as your main file • Also need to include the package graphicx in your preamble

Figures • Begin the figure environment by \begin{figure}[placement] • placement is an optional argument that tells LaTeX where on the page you want the figure • Can be h (here), t (top), b (bottom), or p (on a separate page) • Put an ! before the placement if you really want the figure at that page location

Figures • Include the file that you want • \includegraphics[display]{filename} • display is an optional parameter which allows you to change the appearance of your graphic • Can use the following parameters: • width, height, angle (rotates the graphic counterclockwise), scale (number between 0 and 1) • Changing width or height will preserve the aspect ratio

Figures • Can create a caption for your figure • \caption[shortname]{longname} • shortname is displayed in the Table of Contents (if you create one) • longname is displayed below the figure • Captioning also automatically labels your figures • Can label your figure • \label{reference} • Allows you to refer to your figure later by using \ref{reference}

Figures • End the figure environment • \end{figure} • May sometimes need to create a PostScript file instead of a PDF file in order to get graphics to display properly

Making Math Look Pretty – or How to Use LaTeX