Math

As a first recourse, inline mathematics should be captured using text formatting elements (<sub>, <sup>, <italic>, and so on) and/or Unicode characters.

For display formulas—those which require a numerical reference—and inline formulas where it is not possible to capture the symbols properly using text, the maths should be rendered as both a .gif image (maximum 660 pixels wide) and in MathML. Both formats should be included in an <alternatives> element within the <disp-formula> or <inline-formula> element as appropriate.

Where LaTeX code is available, it should be encoded within a CDATA section within a <tex-math> element.

Mathematical symbols and expressions that appear in titles, such as the title of an article, should be coded using Unicode characters text formatting elements. The use of images or MathML in the title of an article should be avoided.

Display formula

Within a <disp-formula> element, <label> should be used to capture the numerical reference of the formula (within brackets or parentheses as the journal style requires—usually parentheses).

One <disp-formula> can contain multiple formulas if they are to be referred to as a group (i.e., a single reference number would rightly point to all of them).

In-text callouts to formulas should be done using <xref> elements, with an rid attribute matching the <disp-formula>’s id attribute.

Inline formula

<inline-formula> elements should be treated exactly as <disp-formula> elements, except that they have no <label> element and can contain only a single formula. They should still contain an <alternatives> element with both a graphical representation of the formula and a MathML version.

Statement

The <statement> element should be used to tag formal statements such as Theorem, Lemma, Proof, Example, Remark, etc. The content-type attribute of <statement> must be set to one of the following choices to indicate the type of statement:

  • algorithm
  • corollary
  • definition
  • example
  • hypothesis
  • lemma
  • postulate
  • proof
  • proposition
  • remark
  • theorem

This heading should be pulled from the author’s manuscript. In the event that something resembles a statement but does not have a heading, an author query should be raised asking for the heading (or confirmation that the section of text is not a statement).

NOTE: definition in this context refers to a definition given in the form of a statement with a label such as “Definition 1:”. Definitions such as those that may appear in a glossary should be tagged using the <def-list> element.

MathML

MathML should be tagged using mml as the namespace prefix. The MathML namespace (http://www.w3.org/1998/Math/MathML) must be defined on the <article> root element.

An <mml:math> element can appear within any of the following elements: <alternatives>, <bio>, <boxed-text>, <comment>, <def-head>, <disp-formula>, <disp-quote>, <glossary>, <inline-formula>, <notes>, <p>, <source>, <td>, <term>, <term-head>, <th>.

This is a more restrictive set than JATS 1.2 allows, because display issues make it impractical to use MathML in every place in which it is valid.

MathML should specifically not appear in <article-title> elements.

Example:

<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mi>Y</mml:mi> <mml:mo>=</mml:mo> <mml:msup> <mml:mi>&xi;</mml:mi> <mml:mi mathvariant="normal">&top;</mml:mi> </mml:msup> <mml:mi>&alpha;</mml:mi> <mml:mo>+</mml:mo> <mml:msup> <mml:mrow> <mml:mi mathvariant="bold">Z</mml:mi> </mml:mrow> <mml:mi mathvariant="normal">&top;</mml:mi> </mml:msup> <mml:mi>&beta;</mml:mi> <mml:mo>+</mml:mo> <mml:msup> <mml:mrow> <mml:mi mathvariant="bold">U</mml:mi> </mml:mrow> <mml:mrow> <mml:mi mathvariant="normal">&top;</mml:mi> </mml:mrow> </mml:msup> <mml:mi>g</mml:mi> <mml:mo>(</mml:mo> <mml:mi>T</mml:mi> <mml:mo>)</mml:mo> <mml:mo>+</mml:mo> <mml:mi>&epsi;</mml:mi> </mml:math>

MathML tagging can often be extremely long and involved. The output from that is the following:

image mathmlexample

TeX and LaTeX

LaTeX code should be included where available, but is not required. It sits within CDATA, within <tex-math>, within <alternatives>.

<disp-formula id="M0007"> 
<label>(7)</label> 
<alternatives> 
<graphic xlink:href="TMPH_A_770175_M0007.gif"/> 
<tex-math><![CDATA[ \begin{equation} \Delta \nu ^{i0} \approx C_{i0} |\Delta \nu _{i0} |^\xi, \end{equation} ]]></tex-math>  
<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML">...</mml:math>  
</alternatives>  
</disp-formula>

Examples

Display math

<disp-formula id="M0007"> <label>(7)</label> <alternatives> <graphic xlink:href="TMPH_A_770175_M0007.gif"/> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mi mathvariant="normal">&#x394;</mml:mi> <mml:msup> <mml:mi>&#x3bd;</mml:mi> <mml:mrow> <mml:mi>i</mml:mi> <mml:mn>0</mml:mn> </mml:mrow> </mml:msup> <mml:mo>&#x2248;</mml:mo> <mml:msub> <mml:mi>C</mml:mi> <mml:mrow> <mml:mi>i</mml:mi> <mml:mn>0</mml:mn> </mml:mrow> </mml:msub> <mml:mrow> <mml:mo stretchy="false">|</mml:mo> </mml:mrow> <mml:mi mathvariant="normal">&#x394;</mml:mi> <mml:msub> <mml:mi>&#x3bd;</mml:mi> <mml:mrow> <mml:mi>i</mml:mi> <mml:mn>0</mml:mn> </mml:mrow> </mml:msub> <mml:msup> <mml:mrow> <mml:mo stretchy="false">|</mml:mo> </mml:mrow> <mml:mi>&#x3be;</mml:mi> </mml:msup> <mml:mo>,</mml:mo> </mml:math> </alternatives> </disp-formula>

Inline math

<p>After 30 min, unreacted <inline-formula id="ilm0001"><alternatives><inline-graphic xlink:href="CFAI_A_629314_ILM0001.gif"/><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mtext>N</mml:mtext> <mml:msubsup><mml:mtext>O</mml:mtext><mml:mtext>2</mml:mtext><mml:mo>-</mml:mo></mml:msubsup></mml:mrow></mml:math></alternatives></inline-formula> was eliminated by the addition of 7 mg of ammonium sulfamate in 140 &#x00B5;L of water until there were no more bubbles.</p>

Statement

<statement content-type="theorem"><label>Theorem 1.2:</label><p>When <inline-formula><alternatives><inline-graphic xlink:href="TCON_A_787494_ILM0004.gif"/><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mfrac><mml:mi>K</mml:mi><mml:mi>&rho;</mml:mi></mml:mfrac><mml:mo>&ne;</mml:mo><mml:mfrac><mml:mrow><mml:mi>E</mml:mi><mml:mi>I</mml:mi></mml:mrow><mml:msub><mml:mi>I</mml:mi><mml:mi>&rho;</mml:mi></mml:msub></mml:mfrac></mml:mrow></mml:math></alternatives></inline-formula> and &verbar;&alpha;<sub><italic>j</italic> 
</sub>&verbar;&ne;&verbar;&beta;<sub><italic>j</italic></sub>&verbar;(<italic>j</italic> &equals; 1, 2), the energy functional of the system (<xref ref-type="disp-formula" rid="m0007">1.7</xref>) decays exponentially for any &tau; &gt; 0.</p></statement>