Floating Objects

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< Visuals | Graphics | Using Graphics >

Floats are elements like tables or figures that are placed (and numbered) automatically by TeX. They are so called as they can float around the output pages to a place where TeX thinks they are appropriate (You can influence what TeX thinks as appropriate).

Floats are ConTeXt's "base class" for everything that uses a \place... command (table, figure, own floats).

If you search options of e.g. \placeexternalfigure you must look after \placefloat in the manual! (same for \setup... etc.)

The float types "graphic", "figure", "table" and "intermezzo" are readily defined. If you need more (i.e. if you need another numbering or table of something), you can easily define your own floats with \definefloat.

\placefloat[place][reference]{caption}{some float}

place is one or several (comma separated) of:

preferenceresult
leftleft of text
rightright of text
herepreferably here
topat top of page
bottomat bottom of page
inleftin left margin
inrightin right margin
inmarginin the margin (left or right)
marginin the margin (margin float)
pageon a new (empty) page
oppositeon the left page
90orientation (rotation angle), both caption and contents
alwaysprecedence over stored floats
forceper se here
split(For TABLES only) split tables

(table copied from the manual)

\placefigure and \placetable also accept the same set of options, and allow to create floating figures and captions respectively.

reference

If you don't need to refer to your float, you can leave this parameter out.

Examples

I will explain the examples in terms of \placefigure but the same set of options are also valid for other floats.

  • If you do not want a caption
\placefigure[none] {} {\externalfigure[figurename]}


  • If you do not want the figure to be numbered (but still want the caption)
\placefigure [nonumber] {caption} {\externalfigure[figurename]}
  • Suppose you want the figure to be placed on the right side of the page, a few lines into the paragraph, and want the rest of the paragraph to wrap around the figure
\placefigure [right,2*line] {caption} {\externalfigure[figurename]}

or

\placefigure [right,2*hang] {caption} {\externalfigure[figurename]}

This does not work correctly at a page boundary. The line option leaves the space above the figures empty, while the hang option also wraps texts above the figure.

Floats and columns

This special case is discussed here.

Protruding Floats in Double-Sided Documents

If you have a double-sided document with wide outer margins then you might want your figures to protrude into the margin. In a double-sided document you need to tell ConTeXt to decide whether to make the figure protrude to the left or the right. This can be done as follows:

\definefloat[textmarginfigure][textmarginfigures]
\setupfloat[textmarginfigure][location=inner]
\placetextmarginfigure{\externalfigure[figurename]}

The following code gives a full example that can be pasted into live ConTeXt:

\setuppagenumbering [alternative=doublesided]
\setuplayout[location=middle,backspace=2pc, width=20pc]
\definefloat[textmarginfigure][textmarginfigures]
\setupfloat[textmarginfigure][location=inner]
\starttext
\input knuth
\placetextmarginfigure[here]{}{\externalfigure[figurename][width=30pc]}
\input knuth
\placetextmarginfigure[here]{}{\externalfigure[figurename][width=30pc]}
\input knuth
\stoptext

Landscape Floats in a Portrait Document

Wide tables, for example, can be turned and most likely will need to be put on a separate page.

\startplacetable [location={page,90},title=Table caption]
    \bTABLE [textwidth=\textheight]
        put a wide table here...
    \eTABLE
\stopplacetable

Both the table caption and the contents will be rotated, but not the page header and footer which remain "upright". Notice that one must set the TABLE textwidth to \textheight in order for the table macros to fit properly.

Floats and section headings

By default, section headings don't wrap "around" floating objects. Instead, they will be moved down as far as needed to appear below the float. This behaviour can be controlled using the aligntitle option of the \setupheads or \setuphead commands.

Captions

To change the style of figure(table) captions, use \setupcaptions.

To use a different (e.g. abbreviated) caption in the list of floats, you can do:

\defineselector[caption][max=2,n=2]
\starttext
\setupselector[caption][n=1]
\completelistoffigures
\setupselector[caption][n=2]
\placefigure[][]
{\select{caption}
 {Short caption for list}
 {A rather longer caption which will appear below the figure itself}}
 {This is the content of the actual figure}
\stoptext

Or in more recent (circa November 2011 and later) versions of ConTeXt:

\startplacefigure[title={A rather long caption},list={A short caption}]
This is the content of the actual figure
\stopplacefigure

Flushing floats

The command \placefloats outputs all pending floats.