Selecting special instrument scores

Another question is : ``can I write an orchestral score and extract the separate scores for individual instruments ?'' The answer is 95 % yes : in fact, you can define your own macros \ mynotes...\enotes, \myNotes...\enotes with as many arguments as there are in the orchestral score (hope this is less or equal to 9, but TEXperts know how to work around) and change its definition depending on the selected instrument (or insert a test on the value of some selection register). But the limitation is that the numbering of instruments may change, so that \signatureiii may have to become \signaturei if instrument iii is alone. But, in turn, this is not a serious problem for average TEX wizard apprentices.