Source code for cltk.prosody.grc

This program returns the prosimetric scansion of Greek texts.

A user is first prompted to supply the file path of the text they wish to scan.
Note that this text must be a relatively 'clean' text, as the opening function
(i.e., tokenize) will only remove numbers and all punctuation that is not a
period. The tokenizer will also force lower case on the text. The text will
then be tokenized and syllabified. Before the text undergoes the actual
scansion functions, the text will be re-tokenized into a simple list of words
and syllables. Finally, the simplified tokenized text will be scanned according
to typical Greek scansion rules. The details of these rules are delineated in
the docstrings of the specific scansion functions. The final output is the
resulting scansion.

.. warning::
    Known bug: Reduplicated syllables in a single sentence are not scanned separately.

from typing import List

from cltk.core.cltk_logger import logger

__author__ = ["Tyler Kirby <>"]
__license__ = "MIT License"

# noinspection PyProtectedMember
[docs]class Scansion: """Scans Greek texts that already contain macronized (i.e., long and shorts) texts. """ def __init__(self) -> None: """Setup class variables.""" self.vowels = ["ε", "ι", "ο", "α", "η", "ω", "υ", "ῖ", "ᾶ"] # type: List[str] self.sing_cons = [ "ς", "ρ", "τ", "θ", "π", "σ", "δ", "φ", "γ", "ξ", "κ", "λ", "χ", "β", "ν", "μ", ] # type: List[str] self.doub_cons = ["ξ", "ζ", "ψ"] # type: List[str] self.long_vowels = ["η", "ω", "ῖ", "ᾶ", "ῦ"] # type: List[str] self.diphthongs = [ "αι", "αῖ", "ευ", "εῦ", "αυ", "αῦ", "οι", "οῖ", "ου", "οῦ", "ει", "εῖ", "υι", "υῖ", "ηῦ", ] # type: List[str] self.stops = ["π", "τ", "κ", "β", "δ", "γ"] # type: List[str] self.liquids = ["ρ", "λ"] # type: List[str] self.punc = [ "!", "@", "#", "$", "%", "^", "&", "*", "(", ")", "-", "_", "=", "+", "}", "{", "[", "]", "1", "2", "3", "4", "5", "6", "7", "8", "9", "0", ",", "'", "᾽", "(", ")", ] # type: List[str] self.punc_stops = ["·", ":", ";"] # type: List[str]
[docs] def scan_text(self, input_string: str) -> List[str]: """The primary method for the class. Args: input_string: A string of macronized text. Returns: List representation of each word's long (``¯``) and short (``˘``) values. >>> from cltk.prosody.grc import Scansion >>> text_string = "νέος μὲν καὶ ἄπειρος, δικῶν ἔγωγε ἔτι. μὲν καὶ ἄπειρος." >>> Scansion().scan_text(text_string) ['˘¯¯¯˘¯¯˘¯˘¯˘˘x', '¯¯˘¯x'] """ syllables = self._make_syllables(input_string) sentence_syllables = self._syllable_condenser(syllables) meter = self._scansion(sentence_syllables) return meter
[docs] def _clean_text(self, text: str) -> str: """Remove input text of extraneous (non-stop) punction (e.g., ``","``). By default, ``":"``, ``";"``, and ``"."`` are defined as stops. Args: text: Text string containing non-stop punctuation. Returns: Text with unnecessary punctuation removed >>> from cltk.prosody.grc import Scansion >>> not_clean = "νέος μὲν καὶ ἄπειρος, δικῶν ἔγωγε ἔτι. μὲν καὶ ἄπειρος." >>> Scansion()._clean_text(not_clean) 'νέος μὲν καὶ ἄπειρος δικῶν ἔγωγε ἔτι. μὲν καὶ ἄπειρος.' """ clean = list() # type: List[str] for char in text: if char in self.punc_stops: clean += "." elif char not in self.punc: clean += char else: pass return ("".join(clean)).lower()
[docs] def _clean_accents(self, text: str) -> str: """Remove most accent marks. This the circumflexes over alphas and iotas in the text since they mark vocalic quantity. Args: text: Text string with accents. Returns: Text string with only accents required for processing. >>> from cltk.prosody.grc import Scansion >>> unclean_accents = "νέος μὲν καὶ ἄπειρος, δικῶν ἔγωγε ἔτι. μὲν καὶ ἄπειρος." >>> Scansion()._clean_accents(unclean_accents) 'νεος μεν και απειρος δικων εγωγε ετι. μεν και απειρος.' """ accents = { "ὲέἐἑἒἓἕἔ": "ε", "ὺύὑὐὒὓὔὕ": "υ", "ὸόὀὁὂὃὄὅ": "ο", "ὶίἰἱἲἳἵἴ": "ι", "ὰάἁἀἂἃἅἄᾳᾂᾃ": "α", "ὴήἠἡἢἣἥἤἧἦῆῄῂῇῃᾓᾒᾗᾖᾑᾐ": "η", "ὼώὠὡὢὣὤὥὦὧῶῲῴῷῳᾧᾦᾢᾣᾡᾠ": "ω", "ἶἷ": "ῖ", "ἆἇᾷᾆᾇ": "ᾶ", "ὖὗ": "ῦ", } text = self._clean_text(text) for char in text: for key in accents: if char in key: accent = accents.get(key) if accent: text = text.replace(char, accent) else: pass return text
[docs] def _tokenize(self, text: str) -> List[List[str]]: """Tokenize the text into a list of sentences with a list of words. Args: text: Text string Returns: List of words within a list of sentences >>> from cltk.prosody.grc import Scansion >>> not_tokenized = "νέος μὲν καὶ ἄπειρος, δικῶν ἔγωγε ἔτι. μὲν καὶ ἄπειρος." >>> Scansion()._tokenize(not_tokenized) [['νεος', 'μεν', 'και', 'απειρος', 'δικων', 'εγωγε', 'ετι.'], ['μεν', 'και', 'απειρος.']] """ sentences = list() tokens = list() for word in self._clean_accents(text).split(" "): tokens.append(word) if "." in word: sentences.append(tokens) tokens = list() return sentences
[docs] @staticmethod def _syllable_condenser(words_syllables: List[List[List[str]]]) -> List[List[str]]: """Reduce a list of ``[sentence[word[syllable]]]`` to ``[sentence[syllable]]``. Args: words_syllables: List of syllables Returns: List of words >>> from cltk.prosody.grc import Scansion >>> input_syllables = [[["νε", "ος"], ["μεν"], ["και"], ["α", "πει", "ρος"], ["δι", "κων"], ["ε", "γω", "γε"], ["ε", "τι"]], [["μεν"], ["και"], ["α", "πει", "ρος"]]] >>> Scansion()._syllable_condenser(input_syllables) [['νε', 'ος', 'μεν', 'και', 'α', 'πει', 'ρος', 'δι', 'κων', 'ε', 'γω', 'γε', 'ε', 'τι'], ['μεν', 'και', 'α', 'πει', 'ρος']] """ sentences_syllables = list() for sentence in words_syllables: syllables_sentence = list() # type: List[str] for word in sentence: syllables_sentence += word sentences_syllables.append(syllables_sentence) return sentences_syllables
[docs] def _long_by_nature(self, syllable: str) -> bool: """Check if syllable is long by nature. Long by nature includes: 1. Syllable contains a diphthong 2. Syllable contains a long vowel Args: syllable: A syllable Returns: Whether or not input is long by nature. >>> from cltk.prosody.grc import Scansion >>> syllables = ["νε", "ος", "μεν", "και", "α", "πει", "ρος", "δι", "κων", "ε", "γω", "γε", "ε", "τι", "μεν", "και", "α", "πει", "ρος"] >>> [Scansion()._long_by_nature(syllable) for syllable in syllables] [False, False, False, True, False, True, False, False, True, False, True, False, False, False, False, True, False, True, False] """ # Find diphthongs vowel_group = list() # type: List[str] for char in syllable: if char in self.long_vowels: return True if char not in self.sing_cons and char not in self.doub_cons: vowel_group += char return bool("".join(vowel_group) in self.diphthongs)
[docs] def _long_by_position(self, syllable: str, sentence: List[str]) -> bool: """Check if syllable is long by position. Returns ``True`` if syllable is long by position Long by position includes contexts when: 1. Next syllable begins with two consonants, unless those consonants are a stop + liquid combination 2. Next syllable begins with a double consonant 3. Syllable ends with a consonant and the next syllable begins with a consonant Args: syllable: Current syllable sentence: Sentence in which syllable appears Returns: Whether or not a syllable is long by position >>> from cltk.prosody.grc import Scansion >>> syllables_sentence = ["μεν", "και", "α", "πει", "ρος"] >>> [Scansion()._long_by_position(syllable=syllable, sentence=syllables_sentence) for syllable in syllables_sentence] [True, False, False, False, False] """ try: next_syll = sentence[sentence.index(syllable) + 1] # Long by position by case 1 if (next_syll[0] in self.sing_cons and next_syll[1] in self.sing_cons) and ( next_syll[0] not in self.stops and next_syll[1] not in self.liquids ): return True # Long by position by case 2 if syllable[-1] in self.vowels and next_syll[0] in self.doub_cons: return True # Long by position by case 3 if syllable[-1] in self.sing_cons and (next_syll[0] in self.sing_cons): return True except IndexError: "IndexError while checking if syllable '%s' is long. Continuing.", syllable, ) return False
[docs] def _scansion(self, sentence_syllables: List[List[str]]) -> List[str]: """Replace long and short values for each input syllable. Args: sentence_syllables: List of word tokens Returns: ``"˘"`` and ``"¯"`` to represent short and long syllables, respectively >>> from cltk.prosody.grc import Scansion >>> syllables_sentence = [["νε", "ος", "μεν", "και", "α", "πει", "ρος", "δι", "κων", "ε", "γω", "γε", "ε", "τι"], ["μεν", "και", "α", "πει", "ρος"]] >>> Scansion()._scansion(syllables_sentence) ['˘¯¯¯˘¯¯˘¯˘¯˘˘x', '¯¯˘¯x'] """ scanned_text = list() for sentence in sentence_syllables: scanned_sent = list() for syllable in sentence: if self._long_by_position(syllable, sentence) or self._long_by_nature( syllable ): scanned_sent.append("¯") else: scanned_sent.append("˘") if len(scanned_sent) > 1: del scanned_sent[-1] scanned_sent.append("x") scanned_text.append("".join(scanned_sent)) return scanned_text
[docs] def _make_syllables(self, sentences_words: str) -> List[List[List[str]]]: """First tokenize, then divide word tokens into a list of syllables. Note that a syllable in this instance is defined as a vocalic group (i.e., vowel or a diphthong). This means that all syllables which are not the last syllable in the word will end with a vowel or diphthong. Todo: * Determine whether a CLTK syllabifier could replace this. Args: sentences_words: Text string Returns: List of list of list of syllables >>> from cltk.prosody.grc import Scansion >>> text_string = "νέος μὲν καὶ ἄπειρος, δικῶν ἔγωγε ἔτι. μὲν καὶ ἄπειρος." >>> Scansion()._make_syllables(text_string) [[['νε', 'ος'], ['μεν'], ['και'], ['α', 'πει', 'ρος'], ['δι', 'κων'], ['ε', 'γω', 'γε'], ['ε', 'τι']], [['μεν'], ['και'], ['α', 'πει', 'ρος']]] """ text = self._tokenize(sentences_words) all_syllables = list() for sentence in text: syll_per_sent = list() for word in sentence: syll_start = 0 # Begins syllable iterator syll_per_word = list() cur_letter_in = 0 # Begins general iterator while cur_letter_in < len(word): letter = word[cur_letter_in] if (cur_letter_in != len(word) - 1) and ( word[cur_letter_in] + word[cur_letter_in + 1] ) in self.diphthongs: cur_letter_in += 1 # Syllable ends with a diphthong syll_per_word.append(word[syll_start : cur_letter_in + 1]) syll_start = cur_letter_in + 1 elif (letter in self.vowels) or (letter in self.long_vowels): # Syllable ends with a vowel syll_per_word.append(word[syll_start : cur_letter_in + 1]) syll_start = cur_letter_in + 1 cur_letter_in += 1 try: last_vowel = syll_per_word[-1][-1] # Last vowel of a word # Modifies general iterator to accomodate consonants after # the last syllable in a word cur_letter_in = len(word) - 1 # Contains all of the consonants after the last vowel in a word leftovers = "" while word[cur_letter_in] != last_vowel: if word[cur_letter_in] != ".": # Adds consonants to leftovers leftovers = word[cur_letter_in] + leftovers cur_letter_in -= 1 # Adds leftovers to last syllable in a word syll_per_word[-1] += leftovers syll_per_sent.append(syll_per_word) except IndexError: "IndexError while making syllables of '%s'. Continuing.", word ) all_syllables.append(syll_per_sent) return all_syllables