parameter 

<h:div class="summary">A parameter describing the computation.</h:div>
<h:div class="description">
  <h:p>A parameter is a broad concept and can describe numeric quantities, objects, keywords, etc. The distinction between keywords and parameters is often fuzzy. ("MINIM" might mean "minimize", while "MINIM=3" might require three iterations to be run. It may help to think of control keywords as boolean parameters.</h:p>
  <h:p>Numeric parameters can describe values in molecules, forcefields or other objects. Often the parameters will be refined or otherwise varied during the calculation. Some parameters may be fixed at particular values or relaxed at different stages in the calculation. Parameters can have errors, gradients and other indications of uncertainty.</h:p>
  <h:p>String/character parameters are often abbreviated in program xml, and this is supported through the
    <h:tt>regex</h:tt>and
    <h:tt>ignoreCase</h:tt>attributes. ?????</h:p>
  <h:p>Parameters will usually be defined separately from the objects and use the
    <h:tt>ref</h:tt>attribute to reference them.</h:p>
  <h:p>Parameters can be used to describe additional constraints. This will probably require the development of a microlanguage and until then may use program-specific mechanisms. A common approach will be to use an array of values (or objects) to represent different xml values for (parts of) the calculation. Thus a conformational change could be specified by an array of several torsion angles.</h:p>
  <h:p>A parameter will frequently have a
    <h:tt>dictRef</h:tt>pointing to a dictionary which may have more information about how the parameter is to be used or the values it can take.</h:p>
  <h:p>The allowable content of
    <h:tt>parameter</h:tt>s may be shown by a "template" in the
    <h:tt>appinfo</h:tt>; this is stil experimental.</h:p>
</h:div>
<h:div class="example" href="parameter1.xml"/>

Element Information

Model

anyCml | ANY element from ANY namespace OTHER than 'http://www.xml-cml.org/schema' | ANY element from LOCAL namespace 'No Namespace'
Children: anyCml

Attributes

QName Type Fixed Default Use Inheritable Annotation
constraint xsd:string optional 
<h:div class="summary">Constraint on a parameter.</h:div>
<h:div class="description">Semantics not yet finalised. We anticipate "fixed", "none" and symbolic relationships to other parameters.</h:div>
convention namespaceRefType optional 
<h:div class="summary">A reference to a convention.</h:div>
<h:div class="description">There is no controlled vocabulary for conventions, but the author must ensure that the semantics are openly available and that there are mechanisms for implementation. The convention is inherited by all the subelements, so that a convention for
  <h:tt>molecule</h:tt>would by default extend to its
  <h:tt>bond</h:tt>and
  <h:tt>atom</h:tt>children. This can be overwritten if necessary by an explicit
  <h:tt>convention</h:tt>.
  <h:p>It may be useful to create conventions with namespaces (e.g.
    <h:tt>iupac:name</h:tt>). Use of
    <h:tt>convention</h:tt>will normally require non-STMML semantics, and should be used with caution. We would expect that conventions prefixed with "ISO" would be useful, such as ISO8601 for dateTimes.</h:p>
  <h:p>There is no default, but the conventions of STMML or the related language (e.g. CML) will be assumed.</h:p>
</h:div>
<h:div class="example" id="ex" href="convGroup1.xml"/>
dictRef namespaceRefType optional 
<h:div class="summary">A reference to a dictionary entry.</h:div>
<h:div class="description">Elements in data instances such as _scalar_ may have a
  <h:tt>dictRef</h:tt>attribute to point to an entry in a dictionary. To avoid excessive use of (mutable) filenames and URIs we recommend a namespace prefix, mapped to a namespace URI in the normal manner. In this case, of course, the namespace URI must point to a real XML doc containing _entry_ elements and validated against STMML Schema.
  <h:p>Where there is concern about the dictionary becoming separated from the doc the dictionary entries can be physically included as part of the data instance and the normal XPointer addressing mechanism can be used.</h:p>
  <h:p>This attribute can also be used on _dictionary_ elements to define the namespace prefix</h:p>
</h:div>
<h:div class="example" href="dictRefGroup1.xml"/>
id idType optional 
<h:div class="summary">A unique ID for an element.</h:div>
<h:div class="description">Id is used for machine identification of elements and in general should not have application semantics. It is similar to the XML ID type as containing only alphanumerics, '_', ',' and '-' and and must start with an alphabetic character. Ids are case sensitive. Ids should be unique within local scope, thus all atoms within a molecule should have unique ids, but separated molecules within a doc (such as a published article) might have identical ids. Software should be able to search local scope (e.g. all atoms within a molecule). However this is under constant review.</h:div>
name xsd:string optional 
<h:div class="summary">Name of the object.</h:div>
<h:div class="description">A string by which the object is known. Often a required attribute. The may or may not be a semi-controlled vocabulary.</h:div>
ref refType optional 
<h:div class="summary">A reference to an element of given type.</h:div>
<h:div class="description">
  <h:tt>ref</h:tt>modifies an element into a reference to an existing element of that type within the doc. This is similar to a pointer and it can be thought of a strongly typed hyperlink. It may also be used for "subclassing" or "overriding" elements.
  <br xmlns=""/>When referring to an element most of the "data" such as attribute values and element content will be on the full instantiated element. Therefore ref (and possibly id) will normally be the only attributes on the pointing element. However there may be some attributes (title, count, etc.) which have useful semantics, but these are element-specific</h:div>
<h:div class="example" href="refGroup1.xml"/>
role xsd:string optional 
<h:div class="summary">Role of the object.</h:div>
<h:div class="description">How the object functions or its position in the architecture. No controlled vocabulary.</h:div>
title xsd:string optional 
<h:div class="summary">A title on an element.</h:div>
<h:div class="description">No controlled value.</h:div>
<h:div class="example" href="title1.xml"/>
value xsd:string optional 
<h:div class="summary">Value of a scalar object.</h:div>
<h:div class="description">The value must be consistent with the dataType of the object.</h:div>
Wildcard: ANY attribute from ANY namespace OTHER than 'http://www.xml-cml.org/schema'

Source 

<xsd:element name="parameter" id="el.parameter" substitutionGroup="anyCml">
  <xsd:annotation>
    <xsd:documentation>
      <h:div class="summary">A parameter describing the computation.</h:div>
      <h:div class="description">
        <h:p>A parameter is a broad concept and can describe numeric quantities, objects, keywords, etc. The distinction between keywords and parameters is often fuzzy. ("MINIM" might mean "minimize", while "MINIM=3" might require three iterations to be run. It may help to think of control keywords as boolean parameters.</h:p>
        <h:p>Numeric parameters can describe values in molecules, forcefields or other objects. Often the parameters will be refined or otherwise varied during the calculation. Some parameters may be fixed at particular values or relaxed at different stages in the calculation. Parameters can have errors, gradients and other indications of uncertainty.</h:p>
        <h:p>String/character parameters are often abbreviated in program xml, and this is supported through the
          <h:tt>regex</h:tt>and
          <h:tt>ignoreCase</h:tt>attributes. ?????</h:p>
        <h:p>Parameters will usually be defined separately from the objects and use the
          <h:tt>ref</h:tt>attribute to reference them.</h:p>
        <h:p>Parameters can be used to describe additional constraints. This will probably require the development of a microlanguage and until then may use program-specific mechanisms. A common approach will be to use an array of values (or objects) to represent different xml values for (parts of) the calculation. Thus a conformational change could be specified by an array of several torsion angles.</h:p>
        <h:p>A parameter will frequently have a
          <h:tt>dictRef</h:tt>pointing to a dictionary which may have more information about how the parameter is to be used or the values it can take.</h:p>
        <h:p>The allowable content of
          <h:tt>parameter</h:tt>s may be shown by a "template" in the
          <h:tt>appinfo</h:tt>; this is stil experimental.</h:p>
      </h:div>
      <h:div class="example" href="parameter1.xml"/>
    </xsd:documentation>
  </xsd:annotation>
  <xsd:complexType>
    <xsd:choice minOccurs="0" maxOccurs="unbounded">
      <xsd:element ref="anyCml"/>
      <xsd:any namespace="##other" processContents="lax"/>
      <xsd:any namespace="##local" processContents="lax"/>
    </xsd:choice>
    <xsd:attributeGroup ref="ref"/>
    <xsd:attributeGroup ref="title"/>
    <xsd:attributeGroup ref="id"/>
    <xsd:attributeGroup ref="convention"/>
    <xsd:attributeGroup ref="dictRef"/>
    <xsd:attributeGroup ref="value">
      <xsd:annotation>
        <xsd:documentation>
          <h:div class="specific">This is a shorthand for a single scalar value of the parameter. It should only be used with the
            <h:tt>ref</h:tt>attribute as it inherits all the dataTyping of the referenced element. It must not be used for defining new parameters as it has no mechanism for units and dataTyping. [This may change?].</h:div>
        </xsd:documentation>
      </xsd:annotation>
    </xsd:attributeGroup>
    <xsd:attributeGroup ref="constraint"/>
    <xsd:attributeGroup ref="name"/>
    <xsd:attributeGroup ref="role">
      <xsd:annotation>
        <xsd:documentation>
          <h:div class="specific">
            <h:p>Used to define concepts such as independent and dependent variables</h:p>
          </h:div>
        </xsd:documentation>
      </xsd:annotation>
    </xsd:attributeGroup>
    <xsd:anyAttribute namespace="##other" processContents="lax"/>
  </xsd:complexType>
</xsd:element>

Sample