from .bases import _StandardStemmer from whoosh.compat import u class SpanishStemmer(_StandardStemmer): """ The Spanish Snowball stemmer. :cvar __vowels: The Spanish vowels. :type __vowels: unicode :cvar __step0_suffixes: Suffixes to be deleted in step 0 of the algorithm. :type __step0_suffixes: tuple :cvar __step1_suffixes: Suffixes to be deleted in step 1 of the algorithm. :type __step1_suffixes: tuple :cvar __step2a_suffixes: Suffixes to be deleted in step 2a of the algorithm. :type __step2a_suffixes: tuple :cvar __step2b_suffixes: Suffixes to be deleted in step 2b of the algorithm. :type __step2b_suffixes: tuple :cvar __step3_suffixes: Suffixes to be deleted in step 3 of the algorithm. :type __step3_suffixes: tuple :note: A detailed description of the Spanish stemming algorithm can be found under http://snowball.tartarus.org/algorithms/spanish/stemmer.html """ __vowels = u("aeiou\xE1\xE9\xED\xF3\xFA\xFC") __step0_suffixes = ("selas", "selos", "sela", "selo", "las", "les", "los", "nos", "me", "se", "la", "le", "lo") __step1_suffixes = ('amientos', 'imientos', 'amiento', 'imiento', 'aciones', 'uciones', 'adoras', 'adores', 'ancias', u('log\xEDas'), 'encias', 'amente', 'idades', 'anzas', 'ismos', 'ables', 'ibles', 'istas', 'adora', u('aci\xF3n'), 'antes', 'ancia', u('log\xEDa'), u('uci\xf3n'), 'encia', 'mente', 'anza', 'icos', 'icas', 'ismo', 'able', 'ible', 'ista', 'osos', 'osas', 'ador', 'ante', 'idad', 'ivas', 'ivos', 'ico', 'ica', 'oso', 'osa', 'iva', 'ivo') __step2a_suffixes = ('yeron', 'yendo', 'yamos', 'yais', 'yan', 'yen', 'yas', 'yes', 'ya', 'ye', 'yo', u('y\xF3')) __step2b_suffixes = (u('ar\xEDamos'), u('er\xEDamos'), u('ir\xEDamos'), u('i\xE9ramos'), u('i\xE9semos'), u('ar\xEDais'), 'aremos', u('er\xEDais'), 'eremos', u('ir\xEDais'), 'iremos', 'ierais', 'ieseis', 'asteis', 'isteis', u('\xE1bamos'), u('\xE1ramos'), u('\xE1semos'), u('ar\xEDan'), u('ar\xEDas'), u('ar\xE9is'), u('er\xEDan'), u('er\xEDas'), u('er\xE9is'), u('ir\xEDan'), u('ir\xEDas'), u('ir\xE9is'), 'ieran', 'iesen', 'ieron', 'iendo', 'ieras', 'ieses', 'abais', 'arais', 'aseis', u('\xE9amos'), u('ar\xE1n'), u('ar\xE1s'), u('ar\xEDa'), u('er\xE1n'), u('er\xE1s'), u('er\xEDa'), u('ir\xE1n'), u('ir\xE1s'), u('ir\xEDa'), 'iera', 'iese', 'aste', 'iste', 'aban', 'aran', 'asen', 'aron', 'ando', 'abas', 'adas', 'idas', 'aras', 'ases', u('\xEDais'), 'ados', 'idos', 'amos', 'imos', 'emos', u('ar\xE1'), u('ar\xE9'), u('er\xE1'), u('er\xE9'), u('ir\xE1'), u('ir\xE9'), 'aba', 'ada', 'ida', 'ara', 'ase', u('\xEDan'), 'ado', 'ido', u('\xEDas'), u('\xE1is'), u('\xE9is'), u('\xEDa'), 'ad', 'ed', 'id', 'an', u('i\xF3'), 'ar', 'er', 'ir', 'as', u('\xEDs'), 'en', 'es') __step3_suffixes = ("os", "a", "e", "o", u("\xE1"), u("\xE9"), u("\xED"), u("\xF3")) def stem(self, word): """ Stem a Spanish word and return the stemmed form. :param word: The word that is stemmed. :type word: str or unicode :return: The stemmed form. :rtype: unicode """ word = word.lower() step1_success = False r1, r2 = self._r1r2_standard(word, self.__vowels) rv = self._rv_standard(word, self.__vowels) # STEP 0: Attached pronoun for suffix in self.__step0_suffixes: if word.endswith(suffix): if rv.endswith(suffix): if rv[:-len(suffix)].endswith((u("i\xE9ndo"), u("\xE1ndo"), u("\xE1r"), u("\xE9r"), u("\xEDr"))): word = (word[:-len(suffix)].replace(u("\xE1"), "a") .replace(u("\xE9"), "e") .replace(u("\xED"), "i")) r1 = (r1[:-len(suffix)].replace(u("\xE1"), "a") .replace(u("\xE9"), "e") .replace(u("\xED"), "i")) r2 = (r2[:-len(suffix)].replace(u("\xE1"), "a") .replace(u("\xE9"), "e") .replace(u("\xED"), "i")) rv = (rv[:-len(suffix)].replace(u("\xE1"), "a") .replace(u("\xE9"), "e") .replace(u("\xED"), "i")) elif rv[:-len(suffix)].endswith(("ando", "iendo", "ar", "er", "ir")): word = word[:-len(suffix)] r1 = r1[:-len(suffix)] r2 = r2[:-len(suffix)] rv = rv[:-len(suffix)] elif (rv[:-len(suffix)].endswith("yendo") and word[:-len(suffix)].endswith("uyendo")): word = word[:-len(suffix)] r1 = r1[:-len(suffix)] r2 = r2[:-len(suffix)] rv = rv[:-len(suffix)] break # STEP 1: Standard suffix removal for suffix in self.__step1_suffixes: if word.endswith(suffix): if suffix == "amente" and r1.endswith(suffix): step1_success = True word = word[:-6] r2 = r2[:-6] rv = rv[:-6] if r2.endswith("iv"): word = word[:-2] r2 = r2[:-2] rv = rv[:-2] if r2.endswith("at"): word = word[:-2] rv = rv[:-2] elif r2.endswith(("os", "ic", "ad")): word = word[:-2] rv = rv[:-2] elif r2.endswith(suffix): step1_success = True if suffix in ("adora", "ador", u("aci\xF3n"), "adoras", "adores", "aciones", "ante", "antes", "ancia", "ancias"): word = word[:-len(suffix)] r2 = r2[:-len(suffix)] rv = rv[:-len(suffix)] if r2.endswith("ic"): word = word[:-2] rv = rv[:-2] elif suffix in (u("log\xEDa"), u("log\xEDas")): word = word.replace(suffix, "log") rv = rv.replace(suffix, "log") elif suffix in (u("uci\xF3n"), "uciones"): word = word.replace(suffix, "u") rv = rv.replace(suffix, "u") elif suffix in ("encia", "encias"): word = word.replace(suffix, "ente") rv = rv.replace(suffix, "ente") elif suffix == "mente": word = word[:-5] r2 = r2[:-5] rv = rv[:-5] if r2.endswith(("ante", "able", "ible")): word = word[:-4] rv = rv[:-4] elif suffix in ("idad", "idades"): word = word[:-len(suffix)] r2 = r2[:-len(suffix)] rv = rv[:-len(suffix)] for pre_suff in ("abil", "ic", "iv"): if r2.endswith(pre_suff): word = word[:-len(pre_suff)] rv = rv[:-len(pre_suff)] elif suffix in ("ivo", "iva", "ivos", "ivas"): word = word[:-len(suffix)] r2 = r2[:-len(suffix)] rv = rv[:-len(suffix)] if r2.endswith("at"): word = word[:-2] rv = rv[:-2] else: word = word[:-len(suffix)] rv = rv[:-len(suffix)] break # STEP 2a: Verb suffixes beginning 'y' if not step1_success: for suffix in self.__step2a_suffixes: if (rv.endswith(suffix) and word[-len(suffix) - 1:-len(suffix)] == "u"): word = word[:-len(suffix)] rv = rv[:-len(suffix)] break # STEP 2b: Other verb suffixes for suffix in self.__step2b_suffixes: if rv.endswith(suffix): if suffix in ("en", "es", u("\xE9is"), "emos"): word = word[:-len(suffix)] rv = rv[:-len(suffix)] if word.endswith("gu"): word = word[:-1] if rv.endswith("gu"): rv = rv[:-1] else: word = word[:-len(suffix)] rv = rv[:-len(suffix)] break # STEP 3: Residual suffix for suffix in self.__step3_suffixes: if rv.endswith(suffix): if suffix in ("e", u("\xE9")): word = word[:-len(suffix)] rv = rv[:-len(suffix)] if len(word) >= 2 and word[-2:] == "gu" and rv[-1] == "u": word = word[:-1] else: word = word[:-len(suffix)] break word = (word.replace(u("\xE1"), "a").replace(u("\xE9"), "e") .replace(u("\xED"), "i").replace(u("\xF3"), "o") .replace(u("\xFA"), "u")) return word