Re: pitch name transpose into numeric per key signature

[Gilles]

Le Sun, 28 Oct 2012 23:16:34 +0100, MING TSANG <address@hidden> a  
écrit:

> (let* ...
>  (scalestep (modulo
>  (- (ly:pitch-notename pitch) (...base of key signature...)) 7))
>  (name (format #f "~a~a"
>  (string-ref "1234567" (scalestep))...

If i well understand what you want, there is a snippet very near of what  
you are searching.
   http://lsr.dsi.unimi.it/LSR/Snippet?id=818
The code below is a "mix" of the code you gave and this snippet.

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
numbr = #(make-engraver (acknowledgers
 ((note-head-interface engraver grob source)
    (let* (
      (context (ly:translator-context engraver))
      (tonic-pitch (ly:context-property context 'tonic))
      (tonic-index (ly:pitch-notename tonic-pitch))
      (event (ly:grob-property grob 'cause))
      (grob-pitch (ly:event-property event 'pitch))
      (grob-index (ly:pitch-notename grob-pitch))
      (delta (modulo (- grob-index tonic-index) 7))
      (name (list-ref '("1" "2" "3" "4" "5" "6" "7") delta))
      (newgrob (ly:engraver-make-grob engraver 'TextScript event)))
   (set! (ly:grob-property newgrob 'text) name)))))

music = \relative c' {
 \key c\major c4 d e f g a b2 |\break
 \key g\major g4 a b c d e fs2 | \break
 \key ef\major ef,4 f g af bf c d2 | \break
 \key d \major d,4 e fs g a b cs2 | \break
 \key cf\major cf,4 df ef ff gf af bf2 | \break
}

\score{
   \new Staff \with {\consists #numbr }
     \music
   \layout {}
}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
--
Gilles