The key-octave element specifies in which octave an element of a key signature appears. The content specifies the octave value using the same values as the display-octave element. The number attribute is a positive integer that refers to the key signature element in left-to-right order. If the cancel attribute is set to yes, then this number refers to an element specified by the cancel element. It is no by default.
<xs:complexType name="key-octave"><xs:annotation><xs:documentation>The key-octave element specifies in which octave an element of a key signature appears. The content specifies the octave value using the same values as the display-octave element. The number attribute is a positive integer that refers to the key signature element in left-to-right order. If the cancel attribute is set to yes, then this number refers to an element specified by the cancel element. It is no by default.</xs:documentation></xs:annotation><xs:simpleContent><xs:extension base="octave"><xs:attribute name="number" type="xs:positiveInteger" use="required"/><xs:attribute name="cancel" type="yes-no"/></xs:extension></xs:simpleContent></xs:complexType>