Re: how to split into two parts

[Gilles Thibault]

> I would like to ask You two questions concerning the code, You've 
> sended:

> 1. How does the function noteToRest "know", that the f sharp has to be
> converted to a rest?

It is not an EventChord, only a NoteEvent

> 2. Is it possible to to convert
>    fis'8 r8
> to
>    r4

You can then use "arranger.ly"

%%%%%%%%%%%%%%%
\version "2.22.0"

\include "arranger.ly"

global = { \time 7/8 s8*7*2 }
#(init '(dummy))

flutes =  {
  <f' g'>8 r fis' 8 r  <d' gis'>8 r8 r
  <f' g'>8  r fis'  <d' gis'>8 r r4 }

noteToRest = #(define-music-function (music) (ly:music?)
  (map-some-music
     (lambda(evt)
       (case (name-of evt) ;; defined in "chordsAndVoices.ly"
         ((EventChord) evt)
         ((NoteEvent) (make-music 'RestEvent
                                  'duration (ly:music-property evt 
'duration)))
         (else #f)))
     music))

flA = \extractNote #2 \flutes
flB = \extractNote #1 \noteToRest \flutes

#(rm 'flB '(1 4) #{ r4 #})

\score { <<
  \new Staff << \global \flutes >>
  \new Staff << \global \flA >>
  \new Staff << \global \flB >>
  >>
}

%%%%%%%%%%%%%%%%

If you want to insert #{ r4 #} in the second beat of several bars, you 
can use x-rm
and apply :

#(apply x-rm 'flB #{ r4 #} (map (lambda(n)(list n 4))
                                '(1 3 7 12 19))) % => '((1 4) (3 4) (7 
4)....)

If the 2 first bars are a rhythmic pattern used a lot of time in the 
piece, you would probably prefer to use the function cp (changePitch).

--
Gilles