Floats, Figures & Tables¶

Topic: LaTeX Lesson: 6 of 16 Prerequisites: Document Structure, Packages Objective: Master the placement and management of figures, images, and tables using LaTeX's float system, including captions, labels, cross-references, and advanced positioning techniques.

Introduction¶

One of the most common sources of frustration for LaTeX beginners is that figures and tables don't appear exactly where you put them in the source code. This is because LaTeX treats these as floats—objects that "float" to optimal positions to avoid awkward page breaks and maintain good typography. This lesson explains how the float system works and how to control it effectively.

What Are Floats?¶

Floats are containers for content that shouldn't be split across pages, such as: - Figures (images, diagrams) - Tables - Algorithms (with specialized packages)

Why LaTeX Uses Floats¶

Consider this scenario: you're writing text and insert a large image. If placed exactly where you wrote it, the image might: - Leave a large white space at the bottom of the page - Split across two pages (unreadable) - Push a single line of text to the next page

LaTeX's float system automatically finds the best position, considering: - Page balance - Proximity to references - Avoiding awkward breaks

The Trade-off¶

Benefit: Professional-looking documents with optimal spacing
Cost: You lose exact positional control
Solution: Use labels and references (Figure~\ref{fig:name}) instead of "the figure below"

The figure Environment¶

The basic syntax:

\begin{figure}[placement]
  % content (usually \includegraphics)
  \caption{Description of the figure}
  \label{fig:identifier}
\end{figure}

Position Specifiers¶

The optional [placement] parameter suggests where the float should go:

h - here (approximately at the source location)
t - top of page
b - bottom of page
p - on a special page containing only floats
! - override LaTeX's internal restrictions
H - exactly Here (requires float package, prevents floating)

Combine specifiers to give LaTeX options:

\begin{figure}[htbp]
  % LaTeX tries: here, then top, then bottom, then float page
\end{figure}

Best practice: Use [htbp] as default. LaTeX chooses the best from these options.

Position Specifier Details¶

% Try to place here
\begin{figure}[h]
  ...
\end{figure}

% Top of page preferred
\begin{figure}[t]
  ...
\end{figure}

% Bottom only
\begin{figure}[b]
  ...
\end{figure}

% Float page only (useful for large figures)
\begin{figure}[p]
  ...
\end{figure}

% Override restrictions (use sparingly)
\begin{figure}[!ht]
  ...
\end{figure}

Including Graphics¶

The graphicx Package¶

First, load the package:

\usepackage{graphicx}

Basic Image Inclusion¶

\begin{figure}[htbp]
  \centering
  \includegraphics{filename}
  \caption{My image}
  \label{fig:myimage}
\end{figure}

Note: You can omit the file extension. LaTeX will find filename.pdf, filename.png, etc.

Sizing Options¶

Control image size with optional parameters:

% Set width
\includegraphics[width=0.8\textwidth]{image}

% Set height
\includegraphics[height=5cm]{image}

% Scale proportionally
\includegraphics[scale=0.5]{image}

% Set both (may distort if aspect ratio doesn't match)
\includegraphics[width=8cm,height=6cm]{image}

% Maintain aspect ratio while fitting in a box
\includegraphics[width=8cm,height=6cm,keepaspectratio]{image}

Common Width Specifications¶

% Relative to text width
\includegraphics[width=0.5\textwidth]{image}  % 50% of text width
\includegraphics[width=\textwidth]{image}     % full text width

% Relative to line width (same as \textwidth in single-column)
\includegraphics[width=0.8\linewidth]{image}

% Absolute measurements
\includegraphics[width=10cm]{image}
\includegraphics[width=4in]{image}

Rotation¶

\includegraphics[angle=90]{image}
\includegraphics[angle=45,width=5cm]{image}

Complete Example¶

\documentclass{article}
\usepackage{graphicx}

\begin{document}

\section{Results}

Figure~\ref{fig:plot} shows the experimental data.

\begin{figure}[htbp]
  \centering
  \includegraphics[width=0.7\textwidth]{experiment_plot}
  \caption{Experimental results showing linear relationship between variables.}
  \label{fig:plot}
\end{figure}

As we can see in Figure~\ref{fig:plot}, the correlation is clear.

\end{document}

Supported Image Formats¶

The supported formats depend on your LaTeX engine:

pdfLaTeX¶

PDF - vector graphics (best quality)
PNG - raster graphics, lossless
JPG/JPEG - raster graphics, lossy (photos)
EPS - requires conversion (use epstopdf package)

XeLaTeX / LuaLaTeX¶

All formats supported by pdfLaTeX
EPS - direct support

Best Practices¶

Vector graphics (PDF, EPS): For diagrams, plots, mathematical figures
Scales perfectly
Small file size
Created by: TikZ, Matplotlib (.pdf), R, Inkscape
Raster graphics (PNG, JPG): For photographs, screenshots
Use high resolution (300 DPI for print)
PNG for screenshots, diagrams with transparency
JPG for photographs
Avoid: BMP, TIFF (large file sizes)

Graphics Path¶

Set a default directory for images:

\graphicspath{{images/}{figures/}{./plots/}}

Now you can use:

\includegraphics{myplot}  % searches in images/, figures/, plots/

Captions¶

Basic Captions¶

\caption{Description of the figure}

The caption is automatically numbered and labeled as "Figure 1:", "Figure 2:", etc.

Short Captions for List of Figures¶

\caption[Short title]{Long detailed description that appears under the figure}

The short version appears in the list of figures (see below).

Caption Positioning¶

% Caption below (standard for figures)
\begin{figure}[htbp]
  \centering
  \includegraphics[width=0.6\textwidth]{image}
  \caption{Below the image}
\end{figure}

% Caption above (common for tables)
\begin{figure}[htbp]
  \centering
  \caption{Above the image}
  \includegraphics[width=0.6\textwidth]{image}
\end{figure}

Convention: Captions below figures, above tables.

Caption Customization¶

Use the caption package for extensive customization:

\usepackage{caption}

% Global caption settings
\captionsetup{
  font=small,
  labelfont=bf,
  format=hang,
  justification=justified
}

Per-float customization:

\captionsetup[figure]{labelfont={bf,it}}
\captionsetup[table]{labelfont=sc}

Labels and Cross-References¶

Creating Labels¶

\begin{figure}[htbp]
  \centering
  \includegraphics[width=0.5\textwidth]{diagram}
  \caption{System architecture}
  \label{fig:architecture}  % Label AFTER caption
\end{figure}

Important: Place \label{} after \caption{}, otherwise the reference number may be wrong.

Referencing Figures¶

% Basic reference (produces number only: "1")
See Figure~\ref{fig:architecture}.

% With \autoref (requires hyperref package)
See \autoref{fig:architecture}.  % produces "Figure 1"

% Page reference
See Figure~\ref{fig:architecture} on page~\pageref{fig:architecture}.

Best Practices for Labels¶

Prefix convention:
fig: for figures
tab: for tables
eq: for equations
sec: for sections
ch: for chapters
Descriptive names: fig:network_topology better than fig:1
Consistent naming: Use underscores or hyphens consistently

The hyperref Package¶

\usepackage{hyperref}

Benefits: - Clickable cross-references (in PDF) - Automatic "Figure", "Table", "Section" with \autoref{} - Colored or boxed links (customizable)

\usepackage[colorlinks=true, linkcolor=blue, citecolor=green]{hyperref}

Subfigures¶

The subcaption Package¶

\usepackage{subcaption}

Basic Subfigures¶

\begin{figure}[htbp]
  \centering
  \begin{subfigure}{0.45\textwidth}
    \centering
    \includegraphics[width=\textwidth]{image1}
    \caption{First subfigure}
    \label{fig:sub1}
  \end{subfigure}
  \hfill
  \begin{subfigure}{0.45\textwidth}
    \centering
    \includegraphics[width=\textwidth]{image2}
    \caption{Second subfigure}
    \label{fig:sub2}
  \end{subfigure}
  \caption{Two subfigures side by side}
  \label{fig:both}
\end{figure}

Reference them:

Figure~\ref{fig:both} shows two cases. Figure~\ref{fig:sub1} shows...

Multiple Rows¶

\begin{figure}[htbp]
  \centering
  % First row
  \begin{subfigure}{0.3\textwidth}
    \centering
    \includegraphics[width=\textwidth]{img1}
    \caption{Image 1}
  \end{subfigure}
  \hfill
  \begin{subfigure}{0.3\textwidth}
    \centering
    \includegraphics[width=\textwidth]{img2}
    \caption{Image 2}
  \end{subfigure}
  \hfill
  \begin{subfigure}{0.3\textwidth}
    \centering
    \includegraphics[width=\textwidth]{img3}
    \caption{Image 3}
  \end{subfigure}

  % Second row
  \begin{subfigure}{0.3\textwidth}
    \centering
    \includegraphics[width=\textwidth]{img4}
    \caption{Image 4}
  \end{subfigure}
  \hfill
  \begin{subfigure}{0.3\textwidth}
    \centering
    \includegraphics[width=\textwidth]{img5}
    \caption{Image 5}
  \end{subfigure}
  \hfill
  \begin{subfigure}{0.3\textwidth}
    \centering
    \includegraphics[width=\textwidth]{img6}
    \caption{Image 6}
  \end{subfigure}

  \caption{Six subfigures in a 2×3 grid}
  \label{fig:grid}
\end{figure}

Subfigure Variations¶

% Vertical arrangement
\begin{figure}[htbp]
  \centering
  \begin{subfigure}{\textwidth}
    \centering
    \includegraphics[width=0.6\textwidth]{wide_image}
    \caption{Top image}
  \end{subfigure}

  \begin{subfigure}{\textwidth}
    \centering
    \includegraphics[width=0.6\textwidth]{another_wide}
    \caption{Bottom image}
  \end{subfigure}
  \caption{Vertically stacked subfigures}
\end{figure}

The table Environment¶

The table environment is a wrapper for tabular (the actual table content):

\begin{table}[htbp]
  \centering
  \caption{Experimental results}
  \label{tab:results}
  \begin{tabular}{lcc}
    \hline
    Method & Accuracy & Time (s) \\
    \hline
    A & 95.3\% & 12.4 \\
    B & 97.1\% & 18.7 \\
    C & 94.8\% & 9.3 \\
    \hline
  \end{tabular}
\end{table}

Note: We'll cover advanced table formatting in Lesson 07.

Float Placement Strategies¶

The [H] Specifier¶

The float package provides the H option (note: capital H):

\usepackage{float}

\begin{figure}[H]
  \centering
  \includegraphics[width=0.5\textwidth]{image}
  \caption{Placed exactly here}
\end{figure}

Warning: [H] prevents floating entirely. Use sparingly, as it can create bad page breaks.

Forcing Float Output¶

If floats accumulate without being placed:

\clearpage  % Forces all pending floats to be placed

Or use \FloatBarrier from the placeins package:

\usepackage{placeins}

\section{Introduction}
% content with figures

\FloatBarrier  % Ensure all floats appear before next section

\section{Methods}

Float Parameters¶

Control LaTeX's float placement algorithm:

% Maximum fraction of page that can be floats
\renewcommand{\topfraction}{0.85}      % at top
\renewcommand{\bottomfraction}{0.7}    % at bottom
\renewcommand{\textfraction}{0.15}     % minimum text on page with floats
\renewcommand{\floatpagefraction}{0.66} % minimum fraction for float page

Default values are conservative. Adjusting them can help if figures are being pushed too far.

Wrapping Text Around Figures¶

The wrapfig Package¶

\usepackage{wrapfig}

\begin{wrapfigure}{r}{0.4\textwidth}
  \centering
  \includegraphics[width=0.38\textwidth]{image}
  \caption{Wrapped figure}
\end{wrapfigure}

Lorem ipsum dolor sit amet, consectetur adipiscing elit...

Parameters: - {r} or {l} - right or left side - {0.4\textwidth} - width of the wrap area

Caveats: - Can be tricky with page breaks - Works best in middle of paragraphs - Avoid near lists or section headings

Side-by-Side Figures with minipage¶

An alternative to subfigures:

\begin{figure}[htbp]
  \centering
  \begin{minipage}{0.45\textwidth}
    \centering
    \includegraphics[width=\textwidth]{image1}
    \caption{First image}
    \label{fig:first}
  \end{minipage}
  \hfill
  \begin{minipage}{0.45\textwidth}
    \centering
    \includegraphics[width=\textwidth]{image2}
    \caption{Second image}
    \label{fig:second}
  \end{minipage}
\end{figure}

Difference from subfigures: - Each gets its own figure number (Figure 1, Figure 2) - Subfigures share a number (Figure 1a, Figure 1b)

Centering: \centering vs center¶

Two ways to center content:

% Method 1: \centering command (preferred in floats)
\begin{figure}[htbp]
  \centering
  \includegraphics[width=0.5\textwidth]{image}
  \caption{Centered with command}
\end{figure}

% Method 2: center environment (adds vertical space)
\begin{figure}[htbp]
  \begin{center}
    \includegraphics[width=0.5\textwidth]{image}
  \end{center}
  \caption{Centered with environment}
\end{figure}

Best practice: Use \centering in floats. The center environment adds extra vertical space above and below, which is usually unwanted inside figures.

Lists of Figures and Tables¶

Creating Lists¶

\documentclass{article}
\usepackage{graphicx}

\begin{document}

\tableofcontents
\listoffigures  % List of Figures
\listoftables   % List of Tables

\section{Introduction}
% content with figures and tables

\end{document}

Short Captions in Lists¶

\begin{figure}[htbp]
  \centering
  \includegraphics[width=0.8\textwidth]{complex_diagram}
  \caption[Neural network architecture]{
    Complete neural network architecture showing input layer (784 neurons),
    two hidden layers (256 and 128 neurons), and output layer (10 neurons)
    with dropout and batch normalization.
  }
  \label{fig:nn}
\end{figure}

The list of figures shows: "Neural network architecture"

The caption under the figure shows the full description.

Complete Example: Research Paper¶

\documentclass{article}
\usepackage{graphicx}
\usepackage{subcaption}
\usepackage{hyperref}

\graphicspath{{figures/}}

\begin{document}

\title{Image Classification Study}
\author{Author Name}
\maketitle

\listoffigures

\section{Introduction}

This study examines three different architectures for image classification.

\section{Methods}

We evaluated the architectures shown in Figure~\ref{fig:architectures}.

\begin{figure}[htbp]
  \centering
  \begin{subfigure}{0.3\textwidth}
    \centering
    \includegraphics[width=\textwidth]{cnn_arch}
    \caption{CNN}
    \label{fig:cnn}
  \end{subfigure}
  \hfill
  \begin{subfigure}{0.3\textwidth}
    \centering
    \includegraphics[width=\textwidth]{resnet_arch}
    \caption{ResNet}
    \label{fig:resnet}
  \end{subfigure}
  \hfill
  \begin{subfigure}{0.3\textwidth}
    \centering
    \includegraphics[width=\textwidth]{vit_arch}
    \caption{ViT}
    \label{fig:vit}
  \end{subfigure}
  \caption[Architectures]{Three architectures: (a) traditional CNN,
  (b) ResNet with skip connections, (c) Vision Transformer}
  \label{fig:architectures}
\end{figure}

The CNN architecture (Figure~\ref{fig:cnn}) serves as our baseline.

\section{Results}

Table~\ref{tab:results} summarizes the performance.

\begin{table}[htbp]
  \centering
  \caption{Classification accuracy on test set}
  \label{tab:results}
  \begin{tabular}{lcc}
    \hline
    Model & Accuracy & Params (M) \\
    \hline
    CNN & 92.3\% & 1.2 \\
    ResNet & 95.7\% & 23.5 \\
    ViT & 96.4\% & 86.2 \\
    \hline
  \end{tabular}
\end{table}

The Vision Transformer achieves the best accuracy (see Table~\ref{tab:results}).

\section{Conclusion}

Our experiments demonstrate that...

\end{document}

Troubleshooting Float Issues¶

Problem: Too many floats, not enough text¶

Solution: Use \clearpage or \FloatBarrier to force placement.

Problem: Figure appears far from reference¶

Solution: 1. Use more permissive placement options: [!htbp] 2. Adjust float parameters 3. Accept that floats may move (use proper references)

Problem: Large figure leaves big white space¶

Solution: 1. Allow float page placement: [htbp] includes p 2. Use \clearpage before the figure 3. Resize the figure

Problem: "Too many unprocessed floats"¶

Solution: 1. Add \clearpage periodically 2. Reduce number of floats 3. Use [H] for some figures (with float package)

Best Practices Summary¶

Always use floats for figures and tables (don't manually position)
Use labels and references instead of "the figure below"
Place label after caption to get correct reference number
Use descriptive label names with prefixes (fig:, tab:)
Set width relative to \textwidth for consistent sizing
Use vector graphics (PDF) when possible
Use \centering not \begin{center}...\end{center} in floats
Provide short captions for list of figures when caption is long
Use [htbp] as default placement specifier
Don't fight the float system - trust LaTeX's placement algorithm

Exercises¶

Exercise 1: Basic Figure¶

Create a document with three figures using different width specifications (0.5\textwidth, 0.75\textwidth, full width). Add captions and labels, then reference all three in the text.

Exercise 2: Subfigures¶

Create a figure with four subfigures in a 2×2 grid. Add individual subcaptions and a main caption. Reference both the main figure and individual subfigures in the text.

Exercise 3: Mixed Floats¶

Create a document with: - 2 figures - 2 tables - Cross-references to all floats - A list of figures and list of tables

Exercise 4: Figure Sizing¶

Create the same figure at different sizes: - Width-based (0.8\textwidth) - Height-based (6cm) - Scale-based (scale=0.6) - Fixed size (width=10cm, height=8cm, keepaspectratio)

Exercise 5: Float Placement¶

Experiment with placement specifiers. Create several figures with: - [h] - [t] - [b] - [p] - [H] (requires float package)

Observe where LaTeX places them.

Exercise 6: Wrapped Figure¶

Use the wrapfig package to create a figure with text wrapping around it. Ensure the figure appears in the middle of a long paragraph.

Exercise 7: Side-by-Side Comparison¶

Create two side-by-side figures using: 1. The subfigure approach (shared figure number) 2. The minipage approach (separate figure numbers)

Compare the results.

Exercise 8: Research Document¶

Create a mini research paper with: - Title and author - List of figures and tables - 3 sections with text - 3 figures (including one with subfigures) - 2 tables - Proper cross-references throughout

Summary¶

This lesson covered: - Float system basics and why LaTeX uses floats - The figure environment and placement specifiers - Including graphics with \includegraphics - Supported image formats and best practices - Captions, labels, and cross-references - Subfigures with the subcaption package - The table environment - Float placement strategies and troubleshooting - Wrapping text and side-by-side figures - Lists of figures and tables

Understanding floats is essential for creating professional LaTeX documents. While the system may seem restrictive at first, it produces consistently well-formatted output.

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