Introduction

This section will give a general introduction to the concept of lengths in LaTeX, including what lengths are and how they are used to control the layout and formatting of a document.

Length in Latex

In LaTeX, a length is a value that can be used to specify the size or position of various elements in a document, such as the margins, font size, and inter-line spacing. Lengths are typically specified in terms of points, inches, centimeters, or millimeters.

There are several commands in LaTeX that can be used to change the length of various elements in a document. Some of the most commonly used commands include:

Here's an example of how changing the length parameters of one command can affect the output in LaTeX:

\documentclass{article}
\usepackage{lipsum}

\begin{document}

\section{Example}
\subsection{Original}
\lipsum[1][4-8]

\subsection{Increased Line Spacing}
\setlength{\baselineskip}{1.5cm}
\lipsum[1][4-8]

\end{document}

In this example, we have a text in two different sections, in the first section it's the original text, and in the second section, we increased the line spacing, as shown in the following generated output:

Tips:

• The command \baselineskip is used to set the distance between the baselines of consecutive lines in a paragraph. The default value of this command is usually set by the document class, but you can use the \setlength command to change it.
• In the above example \lipsum command is used to generate dummy text.

Here's another example of how changing the length parameters of one command can affect the output in LaTeX:

\documentclass{article}
\usepackage{graphicx}
\begin{document}

\section{Example}
\subsection{Original Image}
\includegraphics[width=4cm]{image.jpg}

\subsection{Increased Image Width}
\setlength{\linewidth}{8cm}
\includegraphics[width=\linewidth]{image.jpg}

\end{document}

In this example, an image is included in two different sections, in the first section it's the original image, and in the second section, the width of the image is increased, as shown in the following generated output:

In above example, the \includegraphics command is used to include an image in a LaTeX document, the command accepts options that can be used to control the size of the image. In the first section, an image is included with a width of 4cm. In the second section, the width of the image increased by setting the value of \linewidth to 8cm.

Define a new length command

You can also define your own length commands with the \newlength command and set their value with the \setlength command. For example, you can define a new length command called \mylength and set its value to 5cm like this:

\newlength{\mylength}
\setlength{\mylength}{5cm}

and then use it in your document. For example, you can use it to specify the size of an image like this:

\includegraphics[width=\mylength]{example.jpg}

LaTeX measurement units

There are several measurement units in LaTeX that can be used to specify lengths, including: