method to calculate how much to give the "partial" indicator where a measure is a pickup
        :return: str which is the lilypond bar length

def getPartialLength(self):
        """ method to calculate how much to give the "partial" indicator where a measure is a pickup
        :return: str which is the lilypond bar length
        """
        indexes = self.GetChildrenIndexes()
        length = 0
        divider = 0
        total = 0
        result = ""
        for v in indexes:
            voice = self.GetChild(v)
            if voice.note_total > length:
                length = voice.note_total
                note_types = voice.GetAllNoteTypes()
                if len(note_types) == 1:
                    total = length
                    result = str(total)
                else:
                    note_types.sort()
                    total = note_types[0]
                    result = str(total)
                    previous = total
                    count = 0
                    for value in note_types[1:]:
                        if previous * 2 == value:
                            result += "."
                        if previous == value:
                            if total >= previous:
                                total -= previous
                            else:
                                total -= previous / 2
                            total += previous / 2
                            value = previous / 2
                        previous = value

                    first_digit = str(int(total))
                    result = first_digit + result[1:]

        return result