What are the rules for numbering measures in pieces with 1st and 2nd endings and Codas?I'm wondering if I should number the first ending and go back to the start and number the first measure as continuing from the first ending?
Actually, normal practice is to omit the first ending measures from the count and number the second ending measures. If the bar number of the first bar of the first ending would normally be, say, m.31, the first bar of the second ending is m.31. If you need to refer to these two measures separately, you would refer to them as m.31 and m.31 bis (or m.31b) respectively.
I just received Exploring Latin Piano by Tim Richards today. It's worth note for this discussion that the book uses an alternative measure numbering scheme which skips numbering for introductions and numbers measures after repeat signs as if the repeated measures had been written. (with a repeat at m.4 the next measure will be numbered m.9 rather than m.5) The author says this was done to reflect how working musicians will think of measure numbers in regard to performance.
It seems you can deviate from the norm if you have a really good justification for doing so.
There's not One True Way to do it. There are a few different methods that make sense in different contexts.
In musical theater, every measure gets its own unique measure number so that places in the music can be unambiguously referred to by everyone. (In fact, this idea is so important that if music is added or removed, the measure numbers stay where they are. If we insert 4 bars between 82 and 83, the new measures become 82A-82D. And if we cut measures, then we leave a hole in the numbering.) 1st/2nd endings aren't very common in musicals, but they are always numbered separately, and linearly as if the repeat markings weren't there.
For singers, it's not uncommon (but also not completely standard) to number repeated measures for each repeat. So for example if a piece starts with a 16-bar repeat, those first 16 bars are numbered 1-16 and 17-32. That is, the measures are numbered as if the music were fully written out, and so if in my example the last measure had 1st/2nd endings, the 1st ending would be 16 and the 2nd would be 32.
In operas, symphonies, and other large classical works, usually the measures aren't numbered at all and instead rehearsal marks are placed regularly throughout the music.
Normal standard is to count the measures. The measure after the second ending goes further as there was no first and second ending. It makes sense, the conductor says measure x the second time around you wouldn't need more numbers. We save that the measures wouldn't have double numbers. I went to look it up here is a Beethoven 3rd symphony the forward repeat is at the end of measure#4, the first repeat ends at measure 155, in page 17 measure# 156 is the start of the second ending and the measure number is a continuation it doesn't start over from the fifth measure in the begin. Look it up the link wasn't good the site is http//www.musedata.org/beethoven/sym-3