The dis and dis.place attributes record the amount and direction of displacement, respectively. The lform and lwidth attributes capture the appearance of the continuation line associated with the octave displacement. The starting point of the octave displacement may be indicated by either a startid, tstamp, tstamp.ges, or tstamp.real attribute, while the ending point may be recorded by either a dur, dur.ges, endid, or tstamp2 attribute. It is a semantic error not to specify one starting and one ending type of attribute. Also, note that the dur attribute is not required because the octave displacement can be visually instantaneous.
<elementSpec ident="octave" module="MEI.cmn">
<desc xml:lang="en">An indication that a passage should be performed one or more octaves above or below
its
written pitch.</desc>
<classes>
<memberOf key="att.common"/>
<memberOf key="att.facsimile"/>
<memberOf key="att.octave.log"/>
<memberOf key="att.octave.vis"/>
<memberOf key="att.octave.ges"/>
<memberOf key="att.octave.anl"/>
<memberOf key="model.controlEventLike.cmn"/>
</classes>
<content>
<rng:zeroOrMore>
</rng:zeroOrMore>
</content>
<constraintSpec ident="octave_start-_and_end-type_attributes_required" scheme="schematron">
<constraint>
<sch:rule context="mei:octave">
<sch:assert test="@startid or @tstamp or @tstamp.ges or @tstamp.real">Must have one of the
attributes: startid, tstamp, tstamp.ges or tstamp.real.</sch:assert>
<sch:assert test="@dur or @dur.ges or @endid or @tstamp2">Must have one of the attributes:
dur, dur.ges, endid, or tstamp2.</sch:assert>
</sch:rule>
</constraint>
</constraintSpec>
<remarks xml:lang="en">
<p>The <att>dis</att> and <att>dis.place</att> attributes record the amount and direction of
displacement, respectively. The <att>lform</att> and <att>lwidth</att> attributes capture
the appearance of the continuation line associated with the octave displacement. The
starting point of the octave displacement may be indicated by either a <att>startid</att>,
<att>tstamp</att>, <att>tstamp.ges</att>, or <att>tstamp.real</att> attribute, while the
ending point may be recorded by either a <att>dur</att>, <att>dur.ges</att>,
<att>endid</att>, or <att>tstamp2</att> attribute. It is a semantic error not to specify one
starting and one ending type of attribute. Also, note that the <att>dur</att> attribute is
not required because the octave displacement can be visually instantaneous.</p>
</remarks>
</elementSpec>