view abcrange.py @ 650:9982077ac9b2

Update tune format files. In the main one, just remove a couple of now deprecated settings that did nothing anyway. For the web format, which is actually the format used to generate the downloadable PDFs, bring it into line with the main format but leave the margins at the default settings. Also remove the deprecated settings.
author Jim Hague <jim.hague@acm.org>
date Thu, 10 Nov 2016 00:47:55 +0000
parents 1b79867b4f35
children 2f6e05d0aba0
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#!/usr/bin/env python3
#
# Find the range of a tune. Do minimal parsing of an ABC input file
# and print the lowest and highest notes therein. Accidentals are
# ignored.
#
# The output is given in purely numeric form, to avoid needing to
# re-parse it in an external script. A single line is printed with
# the highest note followed by a space and the lowest note. Middle C ('C') is
# 100. D an octave about ('d') is 108. D an octave above that ('d'') is
# 205. D below middle C ('d,') is 94. And so on.
#
# For example:
# $./abcrange.py choon.abc
# choon.abc: 112 97
#

import sys

def process(filename, inf):
    highest = 0
    lowest = 1000
    for line in inf:
        line = line.strip()
        # If it is empty or starts "%", ignore it.
        if len(line) == 0 or line[0] == "%":
            continue

        # Is it a header line? I.e. does it start LETTER COLON?
        # If so, ignore.
        start = line[:2]
        if len(start) > 1 and start[1] == ":" and (start[0].isalpha() or start[0] == '+'):
            continue

        # Tune line.
        inchord = False
        note = 0
        notevals = {
            "C": 100,
            "D": 101,
            "E": 102,
            "F": 103,
            "G": 104,
            "A": 105,
            "B": 106,
            "c": 107,
            "d": 108,
            "e": 109,
            "f": 110,
            "g": 111,
            "a": 112,
            "b": 113,
        }
        for c in line:
            if c == "," and note > 0:
                note = note - 7
                continue
            elif c == "'" and note > 0:
                note = note + 7
                continue

            if note > 0:
                if note > highest:
                    highest = note
                if note < lowest:
                    lowest = note
                note = 0

            if c == '"':
                inchord = not inchord
                continue
            if inchord:
                continue

            if c in notevals:
                note = notevals[c]

        if note > 0:
            if note > highest:
                highest = note
            if note < lowest:
                lowest = note
            note = 0

    print("{0}: {1} {2}".format(filename, highest, lowest))

if len(sys.argv) > 1:
    for arg in sys.argv[1:]:
        try:
            inf = open(arg, "r")
            process(arg, inf)
        finally:
            inf.close()
else:
    process("stdin", sys.stdin)