7 LaTeX is a typesetting program that produces excellently typeset

     7 LaTeX is a typesetting program that produces excellently typeset documents.

     8 documents. Typesetting is placing text onto a page with all the style

     8 Typesetting is placing text onto a page with all the style formatting

     9 formatting defined, so that content looks as intended. It is

     9 defined, so that content looks as intended. It is extensively used for

    10 extensively used for producing high quality scientific and

    10 producing high quality scientific and mathematical documents. It may also be

    11 mathematical documents. It is also used for producing other kinds of

    11 used for producing other kinds of documents, ranging from simple one page

    12 documents, ranging from simple one page articles or letters to

    12 articles to complete books. LaTeX is based on the TeX typesetting language.

    13 books. LaTeX is based on the TeX typesetting language.

    13 

    14 

    14 LaTeX is pronounced either as "Lah-tech" or "Lay-tech". 

    15 LaTeX is pronounced either as "Lah-tech" or "Lay-tech"

    15 

    16 

    16 

    17 In this course, we shall use the sample document, ``sample.pdf``, as a

    17 Why LaTeX?

    18 tool to learn various commands of LaTeX. By the end of the sessions on

    18 ~~~~~~~~~~

    19 LaTeX, we will have produced a copy of that document, starting from

    19 

    20 scratch.

    20 A few reasons for using LaTeX - 

    21 

    22   * It produces documents with excellent visual quality.

    23   * It does the typesetting for you, leaving you - the author - to focus on

    24     writing the content. You will appreciate this, as you learn more.

    25   * It makes writing math just as easy as writing simple text.

    26   * It's renowned for it's stability and a virtually bug free code base.

    27   * It is light on your resources as compared to most of the word processors

    28     available today.

    29   * It uses plain text files as input and can give output in a variety of

    30     formats including PDFs and html making it platform independent.

    31   * It is free software (free as in freedom) and gratis too.

    32   * It is widely used and has a large user community.

    33 

    34 

    35 Course Outline

    36 ~~~~~~~~~~~~~~

    37 

    38 In this course, we will learn enough LaTeX to be a able to produce a simple

    39 document with text, tables, figures, math, references and bibliography. We

    40 will also briefly see how to create presentations using LaTeX, such as the

    41 one use for the slides of this course.

    42 

    43 The sample document, ``sample.pdf``, available in the course material, will

    44 serve as a teaching/learning tool to learn LaTeX. During the course, we shall

    45 reproduce this sample document, starting from scratch, in LaTeX

    23 -----------------------------

    48 +++++++++++++++++++++++++++++

    24 

    49 

    25 Let's first look at the basic structure of the sample document.

    50 A look at the sample document gives us an idea about the various elements

    26 

    51 present in the document, that we will be learning during this course.

    27 Slides with screen shots of

    52 

    53 We shall be learning how to add the following elements to our LaTeX

    54 documents.

    31   * Sections

    58   * Sections & Subsections

    32   * Subsections

    59   * Appendices

    33   * Appendix

    39 Writing the source & compiling it

    65 

    40 ---------------------------------

    66 LaTeX is not a Word Processor

    41 

    67 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

    42 Let's begin with a simple hello world, to see how to write a LaTeX

    68 

    43 document and compile it.  Write the following code into the file

    69 What do we mean by LaTeX not being a Word Processor? Suppose we wanted to

    44 ``draft.tex``.  ::

    70 create a simple document as shown in the image below. If one used a normal

    71 word processor, the author would have to worry about setting the font sizes

    72 of the fonts, centering the title, date and author information, etc.

    73 

    74 .. image:: images/latex_not_wp.png

    75    :alt: LaTeX is not a Word Processor

    76 

    77 To generate this document in LaTeX, we just tell it what we want as the

    78 title, author's name, date etc. and what we want as the content. LaTeX takes

    79 care of proper font size ratios and other presentation details.

    80 

    81 ::

    82 

    83   \documentclass{article}

    84   \title{My First Document}

    85   \author{FOSSEE}

    86   \date{January 2011}

    87   \begin{document}

    88      \maketitle

    89      Hello world!

    90   \end{document}

    91 

    92 LaTeX can be considered to be a document based markup language. What we mean

    93 by a markup language is that you mark up pieces of your text to be particular

    94 elements of your document and then a typesetter or processor typesets your

    95 document based on a set of rules. What do we mean by being document-based? It

    96 means, that in LaTeX, you can change the structure of the whole document

    97 consistently, with a few changes in the preamble of the document, with-out

    98 having to change each element separately.

    99 

   100 First steps -- Typesetting a minimal document

   101 ---------------------------------------------

   102 

   103 Let us start with a minimal example to learn how to write a LaTeX document

   104 and compile it to see the **typeset** output.

   105 

   106 To begin, type out the following code into your text editor and save it as

   107 ``draft.tex``. ::

    51 To compile the document, do the following in your terminal::

   114 To compile your document, type the following command in your terminal::

    52 

   115 

    53   $ pdfLaTeX draft.tex

   116   $ pdflatex draft.tex

    57 Note: The ``LaTeX`` command is often used, instead of ``pdfLaTeX`` to

   120 Note: The ``latex`` command is often used, instead of ``pdflatex`` to get the

    58 get the ``dvi`` output. But, throughout this course, we shall use

   121 ``dvi`` output. But, throughout this course, we shall use ``pdflatex`` to

    59 pdfLaTeX to compile our documents.

   122 compile our documents.

   123 

   124 What does it mean?

   125 ~~~~~~~~~~~~~~~~~~

   126 

   127 As we have already seen, LaTeX is a document based markup. The first line,

   128 ``\documentclass{article}``, tells that our document is an article type

   129 document. LaTeX then, typesets the document accordingly. The documentclass

   130 command, defines the structure and formatting of our document.

   131 

   132 The ``begin`` and ``end`` document commands, mark the beginning and the end

   133 of the content of the LaTeX document. The text in between the begin and end

   134 commands is typeset in the output document. 

   135 

   136 A little digression

   137 ~~~~~~~~~~~~~~~~~~~

   138 

   139 Just like in ``bash`` and ``Python``, the commands in LaTeX are

   140 case-sensitive. ``\Documentclass`` is therefore not a valid command. 

   141 

   142 All the commands in LaTeX begin with a ``\``. An environment begins with a

   143 ``begin`` command and ends with an ``end`` command. In our minimal example,

   144 ``document`` is an environment. Only the text enclosed by the begin and end

   145 commands is effected by the environment. 

   146 

   147 So, as expected LaTeX ignores anything that is written after the

   148 ``\end{document}`` command. (The part of the file before the

   149 ``\begin{document}`` command is called the preamble, and is used to

   150 *"configure"* the LaTeX typesetter and change various parameters for

   151 typesetting. Details later.)

   152 

   153 Essentially, anything written after the ``\end{document}`` command turns out

   154 to be a comment. But, how do we write comments with in the document. ``%`` is

   155 the character to indicate comments. Anything written after a ``%`` symbol in

   156 a line, is ignored. For example, we can add a comment to the minimal document

   157 saying, this is our first document in LaTeX, by saying ``% My First LaTeX

   158 document``. 

   159 

   160 But what if we wanted to insert the ``%`` symbol in the document? We can do

   161 so by escaping it with a ``\`` (backslash). ``%`` is one of the many special

   162 characters in LaTeX. The others are, ``~ # $ ^ & _ { } \``. All of them,

   163 except the ``\`` itself, can be inserted by escaping it with a ``\``. To

   164 insert a ``\`` in our document, we use the command ``\textbackslash``. 

   165 

   166 What would happen if we escape a ``\`` with a ``\``? Yes, you guessed it. A

   167 double backslash is actually another command. It inserts a new line in the

   168 typeset document. The ``\\`` command or ``\newline`` command is used to

   169 insert a newline in the output document. Line breaks in the input document,

   170 do not translate into line breaks in the output document. A single line break

   171 in the input document, doesn't cause any change in the output. A single empty

   172 line causes a change in paragraphs in the output. (Multiple empty lines are

   173 equivalent to a single empty line.) Similarly, multiple spaces are treated as

   174 a single space. 

   175 

   176 Adding Structure

   177 ----------------

   178 

   179 Let us now, look at giving the document some basic structure, like title,

   180 sections, etc. 

    62 ------------------

   183 ~~~~~~~~~~~~~~~~~~

    63 

   184 

    64 The documentclass command, defines the structure and formatting of our

   185 As we have already seen, the ``documentclass`` command tells LaTeX, the type

    65 document. LaTeX typsets the document, based on the documentclass.

   186 of the document that we intend to create. Some of the available LaTeX classes

    66 

   187 are, ``article``, ``proc``, ``report``, ``book``, ``slides``, ``letter``.

    67 LaTeX is a document based markup language. 

   188 Each class has a few differences in how the content of the document is

    68 

   189 typeset.

    69 First of all, a markup language is a system of annotating text or

   190 

    70 adding in extra information to the text that specifies it's structure

   191 The ``documentclass`` command also accepts a few optional parameters. For

    71 or presentation.

   192 example::

    72 

   193 

    73 LaTeX is a document based markup and not an element based one. You

   194   \documentclass[12pt,a4paper,oneside,draft]{report}

    74 generally don't have to worry about typesetting each of the elements

   195 

    75 of your document. Choosing an appropriate documentclass, gives you a

   196 ``12pt`` specifies the size of the main font in the document. The relative

    76 suitable typesetting. You as an author can worry about the content of

   197 sizes of the various fonts is maintained, when the font size is changed. If

    77 the document, rather than the appearance or presentation of the

   198 no size is specified, ``10pt`` is assumed by default.

    78 document.

   199 

    79 

   200 ``a4paper`` specifies the size of the paper to be used for the document.

    80 Why should you use it?

   201 

    81 ~~~~~~~~~~~~~~~~~~~~~~

   202 ``draft`` marks the hyphenation and justification problems in the document

    82 

   203 with a small square in the right hand margin of the document, so that they

    83 A few reasons for using LaTeX - 

   204 can be easily spotted.

    84 

    85   * It produces documents with excellent visual quality.

    86   * It does the typesetting for you, leaving you - the author - to

    87     focus on writing the content.

    88   * It makes writing math just as easy as writing simple text.

    89   * It's renowned for it's stability and a virtually bug free code

    90     base.

    91   * It is light on your resources as compared to most of the word

    92     processors available today.

    93   * It uses plain text files as input and can give output in a variety

    94     of formats including PDFs and html making it platform independent.

    95   * It is free software (free as in freedom) and gratis too.

    96   * It is widely used and has a large user community. 

    97 

    98 

    99 ``\begin`` and ``\end`` commands define environments. In our document,

   100 we have the document environment, which defines the beginning and end

   101 of the content of the document. We place all the content of the

   102 document within this environment.

   103 

   104 Also, as you may have noticed, all the commands in LaTeX begin with a

   105 ``\``. Note that they are case sensitive. Command names in LaTeX

   106 usually have only alpha characters. Any characters other than alpha

   107 characters, terminate the command name. Parameters to commands are

   108 passed in ``{ }``.

   109 

   129 ``\begin{document}`` directive. We compile the document to see if the

   224 ``\begin{document}`` directive. We compile the document to see if the details

   130 details appear in the document, but they donot. These details do not

   225 appear in the document, but they donot. These details do not appear in the

   131 appear in the document until we use the ``\maketitle`` command with

   226 document until we use the ``\maketitle`` command with the document

   132 the document environment to instruct LaTeX to place the top matter

   227 environment to instruct LaTeX to place the top matter information into the

   133 information into the document. Now the document has these details, on

   228 document. Now the document has these details, on compiling again.

   134 compiling again.

   141 Next we shall add an abstract to our document. LaTeX provides an

   235 Next we shall add an abstract to our document. LaTeX provides an environment,

   142 environment, for adding an abstract to the document.  ::

   236 for adding an abstract to the document. 

   237 

   238 ::

   161 The abstract environment is placed at the location where we wish it to

   257 The abstract environment is placed at the location where we wish it to appear

   162 appear in the document.

   258 in the document.

   167 Now let's look at how to add (chapters,) sections and sub-sections to

   263 Now let's look at how to add (chapters,) sections and sub-sections to our

   168 our document. Let's add the section headings and sub headings present

   264 document. Let's add the section headings and sub headings present in our

   169 in our sample document to the working copy of our document.

   265 sample document to the working copy of our document.

   180 If the document was a longer document, we could have used a report or

   276 If the document was a longer document, we could have used a report or a book

   181 a book class. (Note: Books donot have the abstract environment.) Let's

   277 class. (Note: Books donot have the abstract environment.) Let's look at what

   182 look at what happens to the document, when we change it to the report

   278 happens to the document, when we change it to the report class.

   183 class.

   279 

   184 

   280 The numbering strangely begins from zero, now. This is because, chapters have

   185 The numbering strangely begins from zero, now. This is because,

   281 an additional sectioning command called ``\chapter``. The chapter is one

   186 chapters have an additional sectioning command called

   282 level above a section and since, our document does not have a ``\chapter``

   187 ``\chapter``. The chapter is one level above a section and since, our

   283 command, the sections are numbered from 0. To change this, we add a chapter

   188 document does not have a ``\chapter`` command, the sections are

   284 command before the first section. We say

   189 numbered from 0. To change this, we add a chapter command before the

   285 

   190 first section. We say::

   286 ::

   194 Now, observe that we now have a chapter title appearing and the

   290 Now, observe that we now have a chapter title appearing and the numbering

   195 numbering starting from 1.

   291 starting from 1.

   198 controlled by a variable called the secnumdepth. By default it is set

   294 controlled by a variable called the secnumdepth. By default it is set to 2.

   199 to 2. We can now, change it to 3 and get numbering for subsubsections

   295 We can now, change it to 3 and get numbering for subsubsections also. 

   200 also.  ::

   296 

   297 ::

   204 What do you expect to happen if we changed the secnumdepth to 1? What

   301 What do you expect to happen if we changed the secnumdepth to 1? What if it

   205 if it is 0? -1? {Lab excercise}

   302 is 0 or -1?

   222 Our sample document is not long enough to warrant a table of contents,

   319 Our sample document is not long enough to warrant a table of contents, but

   223 but let us learn to add a table of contents to a LaTeX document. If

   320 let us learn to add a table of contents to a LaTeX document. If you ever

   224 you ever tried adding a table of contents, to a document in a

   321 tried adding a table of contents, to a document in a wordprocessor, you would

   225 wordprocessor, you would know how much of a trouble it is. In LaTeX,

   322 know how much of a trouble it is. In LaTeX, it is a matter of just one

   226 it is a matter of just one command and placing the command at the

   323 command and placing the command at the location where you would want to have

   227 location where you would want to have the table of contents. Let's now

   324 the table of contents. Let's now add a table of contents to our draft. Now,

   228 add a table of contents to our draft. Now, compile the document and

   325 compile the document and look at the output document. It does not have the

   229 look at the output document. It does not have the table of contents!

   326 table of contents!

   230 

   327 

   231 On the first compilation only the "Contents" heading appears in the

   328 On the first compilation only the "Contents" heading appears in the document,

   232 document, but the actual table does not appear. You will need to

   329 but the actual table does not appear. You will need to compile your document

   233 compile your document once more, for the actual table to appear in

   330 once more, for the actual table to appear in your document. On the first run,

   234 your document. On the first run, LaTeX has gone through your document

   331 LaTeX has gone through your document and generated a temporary file

   235 and generated a temporary file (``.toc``), with the entries that

   332 (``.toc``), with the entries that should go into the table of contents. These

   236 should go into the table of contents. These entries are made, when you

   333 entries are made, when you compile your document for the second time.

   237 compile your document for the second time.

   334 

   238 

   335 Note that any section/block that has been numbered automatically appears in

   239 Note that any section/block that has been numbered automatically

   336 the table of contents. It is possible to get un-numbered sections, for

   240 appears in the table of contents. It is possible to get un-numbered

   337 instance a Preface or a Foreword section to appear in the Table of Contents.

   241 sections, for instance a Preface or a Foreword section to appear in

   338 

   242 the Table of Contents.

   339 Let's change our Introduction section to be an un-numbered one and try to

   243 

   340 make it appear in the table-of-contents. ::

   244 Let's change our Introduction section to be an un-numbered one and try

   245 to make it appear in the table-of-contents.  ::

   250 We shall talk about adding and managing bibliographies, later in the

   345 We shall talk about adding and managing bibliographies, later in the course.

   251 course.

   346 

   252 

   347 Now, that we have the basic structure of the document, let's get into the

   253 Now, that we have the basic structure of the document, let's get into

   348 content and the details of it.

   254 the content and the details of it.

   259 Let's begin with adding the second paragraph to the introduction

   353 Let's begin with adding the second paragraph to the introduction section.

   260 section. Let's place the text of the second para, after the first

   354 Let's place the text of the second para, after the first line, that we

   261 line, that we already have. Now, compile the document. 

   355 already have. Now, compile the document.

   262 

   356 

   263 Notice, that the second para appears in continuation with the previous

   357 As already discussed, we need to an insert an empty line, to insert a new

   264 line. To start a new paragraph in LaTeX, we need to insert an empty

   358 paragraph in LaTeX. Also, notice that the new paragraph is indented.

   265 line. Multiple empty lines are considered as a single empty line. To

   266 start a new line, use the ``\newline`` or ``\\`` command. Notice the

   267 difference (in the output), in starting a new paragraph and starting a

   268 newline. A new paragraph is indented.

   273 Look at the quotation marks around the text, Sigh Pie. They are not

   363 Look at the quotation marks around the text, Sigh Pie. They are not formatted

   274 formatted properly. To place quotation marks in LaTeX, you should use

   364 properly. To place quotation marks in LaTeX, you should use ````` character

   275 ````` character for the left quote & ``'`` character for the right

   365 for the left quote & ``'`` character for the right quote. For double quotes,

   276 quote. For double quotes, they should be used twice.

   366 they should be used twice.

   281 The names of the software tools, Scilab, Matlab, etc. appear in

   371 The names of the software tools, Scilab, Matlab, etc. appear in italics or

   282 italics or emphasized as it is called in LaTeX. To emphasize text, the

   372 emphasized as it is called in LaTeX. To emphasize text, the ``\emph`` command

   283 ``\emph`` command is used.

   373 is used.

   284 

   374 

   285 Let's also add the contents of the subsection "Sub-packages of

   375 Let's also add the contents of the subsection "Sub-packages of Scipy". We

   286 Scipy". We shall add the table as plain text, until we learn how to

   376 shall add the table as plain text, until we learn how to edit tables.

   287 edit tables.

   377 

   288 

   378 Let's try and form a tabular structure by separating the left and right

   289 Let's try and form a tabular structure by separating the left and

   379 columns using spaces. On compiling we find that LaTeX doesn't add multiple

   290 right columns using spaces. On compiling we find that LaTeX doesn't

   380 spaces between words. Just like multiple empty lines, multiple spaces are

   291 add multiple spaces between words. Just like multiple empty lines,

   381 considered as a single space.

   292 multiple spaces are considered as a single space.

   382 

   293 

   383 Also, we notice that ``LaTeX`` starts a new paragraph at the beginning of the

   294 The names of the sub-packages appear in a fixed width font in the

   384 table. To avoid this, we use the ``flushleft`` environment.

   295 sample document provided to us. The headings of the columns appear in

   385 

   296 bold-face. Let's make changes to this effect.

   386 The names of the sub-packages appear in a fixed width font in the sample

   297 

   387 document provided to us. The headings of the columns appear in bold-face.

   298 ``\textbf`` is used to change text to bold face and ``\texttt`` is

   388 Let's make changes to this effect.

   299 used to change text to fixed width font.

   389 

   300 

   390 ``\textbf`` is used to change text to bold face and ``\texttt`` is used to

   301 We could also change the separating - (hyphen) to an em-dash (or

   391 change text to fixed width font.

   302 en-dash) -- is em-dash and --- is an em-dash, to improve the

   392 

   303 appearance of the document.

   393 We could also change the separating - (hyphen) to an em-dash (or en-dash) --

   394 is em-dash and --- is an em-dash, to improve the appearance of the document.

   308 The section on Use of Scipy in this course, contains lists. Let's now

   399 The section on Use of Scipy in this course, contains lists. Let's now add

   309 add lists to our document. The ``enumerate`` environment adds numbered

   400 lists to our document. The ``enumerate`` environment adds numbered lists to

   310 lists to our document and the ``itemize`` environment adds un-numbered

   401 our document and the ``itemize`` environment adds un-numbered lists.

   311 lists. ``\item`` command adds a new entry to a list. Note, that LaTeX

   402 ``\item`` command adds a new entry to a list. Note, that LaTeX can easily

   312 can easily handle nested lists. In fact most environments can be

   403 handle nested lists. In fact most environments can be embedded within other

   313 embedded within other environments, without any problems.

   404 environments, without any problems.

   314 

   405 

   315 LaTeX also has a description list, which shall be looked at, during

   406 LaTeX also has a description list, which shall be an exercise, for you.

   316 the lab sessions.

   407 

   321 Let's now add the footnote to pylab. LaTeX provides a footnote command

   412 Let's now add the footnote to pylab. LaTeX provides a footnote command to add

   322 to add a footnote.

   413 a footnote.

   323 

   414 

   324 We added the footnote with Appendix A, as plain text. But, in case we

   415 We added the footnote with Appendix A, as plain text. But, in case we added

   325 added another Appendix before the section on using ``pylab``, the

   416 another Appendix before the section on using ``pylab``, the footnote will

   326 footnote will have to be edited. To avoid this, LaTeX provides a handy

   417 have to be edited. To avoid this, LaTeX provides a handy system of labels and

   327 system of labels and referencing.

   418 referencing.