equation

equation — A displayed mathematical equation.

Synopsis

Attributes

Common attributes and common linking attributes.

Additional attributes:

  • floatstyle
  • label
  • pgwide (enumeration)
    • “0”
    • “1”

Additional Constraints

  • example must not occur in the descendants of equation
  • figure must not occur in the descendants of equation
  • table must not occur in the descendants of equation
  • equation must not occur in the descendants of equation
  • caution must not occur in the descendants of equation
  • important must not occur in the descendants of equation
  • note must not occur in the descendants of equation
  • tip must not occur in the descendants of equation
  • warning must not occur in the descendants of equation

Description

An equation is a formal mathematical equation (with an optional rather than a required title).

If the MathML Module is used, equation can also contain the mml:math element.

Processing expectations

Formatted as a displayed block. For an inline equation, use inlineequation.

Processing systems that number equations or build a table of equations at the beginning of a document may have difficulty correctly formatting documents that contain both equations with titles and equations without titles. You are advised to use informalequation for equations without titles.

Attributes

Common attributes and common linking attributes.

floatstyle

Specifies style information to be used when rendering the float

label

Specifies an identifying string for presentation purposes

pgwide

Indicates if the element is rendered across the column or the page

Enumerated values:
“0”

The element should be rendered in the current text flow (with the flow column width).

“1”

The element should be rendered across the full text page.

Parents [+]

This element occurs in 72 elements.

Children

The following elements occur in equation: alt, caption (db.caption), info (db.titleforbidden.info), info (db.titleonly.info), mathphrase, mediaobject, mml:*, title, titleabbrev.

Examples

  1 <article xmlns='http://docbook.org/ns/docbook'>
  2 <title>Example equation</title>
    
  4 <equation xml:id="eq.fermat">
    <title>Fermat's Last Theorem</title>
  6   <alt>x^n + y^n ≠ z^n ∀ n ≠ 2</alt>
      <mediaobject>
  8     <imageobject condition="print">
          <imagedata fileref="figs/print/db5d_refeqn01.pdf"/>
 10     </imageobject>
        <imageobject condition="web">
 12       <imagedata fileref="figs/web/db5d_refeqn01.png"/>
        </imageobject>
 14   </mediaobject>
    </equation>
 16 
    </article>
Equation 1. Fermat's Last Theorem

Alternatively, for relatively simple equations such as Fermat's Last Theorem, mathphrase is often sufficient:

  1 <article xmlns='http://docbook.org/ns/docbook'>
  2 <title>Example equation</title>
    
  4 <equation xml:id="eq.fermat.mathphrase">
    <title>Fermat's Last Theorem</title>
  6   <alt>x^n + y^n ≠ z^n ∀ n ≠ 2</alt>
      <mathphrase>x<superscript>n</superscript>
  8 + y<superscript>n</superscript>
    ≠ z<superscript>n</superscript>
 10 ∀ n ≠ 2</mathphrase>
    </equation>
 12 
    </article>
xn + yn ≠ zn ∀ n ≠ 2
Equation 2. Fermat's Last Theorem
Last revised by Norman Walsh on 6 Jun 2011 (git hash: 6ffcc7640bbc5f852a318e452c9f210f03292cb9)