Added support for the pitch number notation

[kichatos]

Added support for the pitch number notation as an alternative to the binary pitch notation to simplify the pitch accent input.

[IllDepence]

Hi,

thanks a lot for the PR!

I think the function is useful but have a few suggestions regarding the code.

• Naming
  • If pitch_svg now acccepts low-high patterns or numbers, the parameter patt should be renamed. I guess a generic pitch_annot would do.
  • Accodingly, the docstring of pitch_svg should then mention that pitch_annot can bei either a low-high pattern or a downstep position.
  • I feel pitch and patt as they stand right now are a bit confusing or at least not very clear. I'm not sure if there are official names for the differnt types of annotating pitch accent (only found this), but since the number notation marks the downstep, I'd suggest renaming pitch_to_pattern to downstep_to_pattern and its parameters to something like downstep_pos and num_mora.
• Instead of trying to convert patt to an int, I'd suggest using isdigit() to test if the input is numeric or not, then testing for the length (existing check + checking if the number is too high case of number notation (e.g. input はな and 5))
• The pitch_to_pattern (or downstep_to_pattern) function should have a minimal docstring explaining what it does.
• Currently pitch_svg not only accepts l, h, L, and H for marking low and high but also 0 and 1 (and, looking at the code, 2—must've also been used in some annotations). This leads to a problem as an input of '10' could either be a downstep at mora position 10 or a high then low pattern. Accordingly 0, 1and 2 should be removed from the lines if accent in ['H', 'h', '1', '2'] and elif accent in ['L', 'l', '0'].
• In your pitch_to_pattern function, I suggest using if, elif, else instead of two subsequent ifs and followed by the "neither of the above" case just below.