When Floats Don’T Float: Fixing Unexpected Latex Figure And Table Positions

Understanding LaTeX’s Floating Behavior

LaTeX handles figures and tables as floats - elements that are not fixed to a specific location on the page but can move around to achieve the best pagination and layout. This floating behavior allows LaTeX to automatically place floats in optimal positions that avoid awkward blank spaces or other formatting issues.

However, LaTeX's algorithm for positioning floats is imperfect. At times, users find floats placed in unsatisfactory locations - stacked up at the end of the document instead of alongside the relevant text, overflowing into the margins, or bumped to a distant page away from the reference citation. Fixing these unexpected float positions requires understanding what causes LaTeX's automated layout decisions to fail.

Common Causes of Misplaced Floats

Floats Placed at the End of the Document

LaTeX prioritizes keeping paragraphs of text together over placing floats early in the document. If LaTeX lacks sufficient room to place multiple successive floats without breaking up a paragraph, it will bump all the floats to the end of the job instead. This behavior stems from LaTeX's optimization to avoid widows/orphans (single lines of paragraphs stranded on a new page) at the expense of float positions. Long unbreakable paragraphs of text are particularly prone to triggering this issue when multiple floats stack up waiting for a turn. In these cases, LaTeX judges that holding floats is a better outcome than risking disconnected single lines of text spread over page breaks.

Floats Forced to Specific Pages

LaTeX encounters conflicts placing floats when users strictly require floats to land on designated pages. For example, the [p] placement specifier forces a float onto the current page - but LaTeX inserts the float at the next available position where it fits, disregarding text flow or the reference location. This can bump the float far away from its first citation in the text. Similarly, a [b] request to place a float at the bottom of the current page succeeds only if sufficient vertical space exists. Otherwise, LaTeX defers the float rather than overriding other parameters that control page composition and geometry.

Floats Overflowing Into Margins

By default, LaTeX prevents floats from intruding into page margins - keeping figures and tables strictly framed by the set text body geometry. However, in some designs with narrow text width and large floats, LaTeX lacks available width to place floats horizontally without overlap. The floats get shifted vertical down the page until LaTeX determines the current page has insufficient space remaining below a given threshold. Then LaTeX defers the float rather than allowing any overflow into margins, even if the next page has room to accommodate width constraints.

Tools for Controlling Float Placement

Several LaTeX packages give users greater authority over float placement behavior:

The float Package

The float package extends LaTeX's native float positioning capabilities through additional location specifiers. For example, passing the [H] modifier to \begin{figure} asks LaTeX to place the float right where it occurs in the source document order, without floated movement:

\begin{figure}[H]
  \centering
    \includegraphics[width=\linewidth]{example-image}
  \caption{An image placed right here without floating} 
\end{figure}

The placeins Package

The placeins package provides commands like \FloatBarrier to constrain where on the page LaTeX can place floats. Invoking \FloatBarrier splits the text flow by restricting floats from crossing its boundary location to maintain proximity with float references:

See the highlighted region in Figure \ref{fig:foo}. 
\FloatBarrier
\begin{figure}[htbp]
  \centering
    \includegraphics[width=\linewidth]{example-image}
  \caption{Example figure}
  \label{fig:foo}
\end{figure}

Strategies for Fixing Float Positioning

Several techniques can help persuade LaTeX to cooperate with desired float placement:

Allow LaTeX Flexibility in Placing Floats

Avoid narrowly defined absolute or relative directives like [h] or [htbp] on every float. These leave LaTeX little latitude to tweak positions. Instead, use liberally permissive [tbp] specifiers to grant LaTeX discretion to locate the optimal page and vertical position:

\begin{figure}[tbp]
  \centering
    \includegraphics[width=\linewidth]{example-image}
  \caption{A float for LaTeX to place with flexibility} 
\end{figure}

Move Floats Within the Source Code

Edit the source .tex document to rearrange floats closer to their first text citation location when feasible. Keeping floats and references in proximity assists LaTeX in avoiding deferred placements downstream:

We analyzed the network topology across all layers, shown later 
in Figure \ref{fig:layers}. Specifically, the routing fabric...

\begin{figure}[tbp]
  \centering
    \includegraphics[width=\linewidth]{network-layers}
  \caption{Network layers considered in our analysis}
  \label{fig:layers} 
\end{figure} 

Adjust Page Geometry Parameters

Increasing margins, columns, or overall text height can expand LaTeX's available area to place wide floats without overflow. For example, pass \setlength to globally modify \textheight and related dimensions:

\setlength{\textheight}{9in} % expand from default 6.5in
\setlength{\topmargin}{0.5in}% reduce from default 1in 

When All Else Fails: Manual Float Placement

If all else fails, force LaTeX to yield to absolute positioning commands:

\begin{figure}[h!]
  \centering
    \includegraphics[width=\linewidth]{example-image}
  \caption{A float placed right here without debate} 
\end{figure}

The [h!] modifier disregard's LaTeX page breaking sensitivities and inserts the float at that precise source location. However, manually overriding LaTeX's automated layout determinations risks introducing new problems with widows/orphans, text body cohesion, or other formatting repercussions.

Conclusion: Balancing Automation With Manual Control

LaTeX gives users tremendous power to automate document formatting - but occasionally its float placement algorithms fail. Solving unexpected float positions involves judiciously asserting additional human guidance over LaTeX's automated decisions. Allow LaTeX enough latitude to exercise its formatting engine, but restrict absolute positioning only to difficult cases. With practice, an optimal balance emerges between automation and manual control over float placements.

Leave a Reply

Your email address will not be published. Required fields are marked *