Editing Non-traditional key signatures

The commonly used <code>\key</code> command sets the <code>keyAlterations</code> property, in the <code>Staff</code> context.

To create non-standard key signatures, set this property directly. The format of this command is a list:

<pre>\set Staff.keyAlterations =
  #`(((octave . step) . alter) ((octave . step) . alter) ...)</pre>
where, for each element in the list, <code>octave</code> specifies the octave (0 being the octave from middle C to the B above), <code>step</code> specifies the note within the octave (0 means C and 6 means B), and <code>alter</code> is <code>,SHARP ,FLAT ,DOUBLE-SHARP</code> etc.

Alternatively, using the more concise format for each item in the list <code>(step . alter)</code> specifies the same alteration holds in all octaves.

For microtonal scales where a “sharp” is not 100 cents, <code>alter</code> refers to the alteration as a proportion of a 200-cent whole tone.

<lilypond version="2.24.0">
\include "arabic.ly"
\relative do' {
  \set Staff.keyAlterations = #`((0 . ,SEMI-FLAT)
                                 (1 . ,SEMI-FLAT)
                                 (2 . ,FLAT)
                                 (5 . ,FLAT)
                                 (6 . ,SEMI-FLAT))
%\set Staff.extraNatural = ##f
  re reb \dwn reb resd
  dod dob dosd \dwn dob |
  dobsb dodsd do do |
}
</lilypond>

[[Category:Contemporary notation]]
[[Category:Pitches]]
[[Category:Contemporary notation]]
[[Category:Staff notation]]
[[Category:Version-specific]]
[[Category:Really cool]]
[[Category:Included in the official documentation]]