Get only preferred sort of nouns from MeCab.Tagger.

mecab_only_pref_nouns.py

#coding: utf-8
import re

import MeCab

def mecab_only_content_nouns(text_u):
    """ Return preferred tokens from result from MeCab.Tagger.

    - preferred tokens = 名詞(一般), 名詞(サ変接続)
     *  exclude symbols
     *  exclude ones with only one hiragana or katakana character

    """

    def condition(s, f): 
        return u"名詞" in f and \
                not u"固有名詞" in f and \
                re.match(u"[0-9a-zA-Z]+|[ぁ-んァ-ヶｦ-ﾟ一-龠]{2,}|^[一-龠]$", s, re.U)

    ret = []
    add = ret.append
    text = text_u.encode('utf-8') # Input must be a str object.
    tagger = MeCab.Tagger()
    node = tagger.parseToNode(text)
    while node:
        surface_u, feature_u = node.surface.decode('utf-8'), node.feature.decode('utf-8')
        #print surface_u, feature_u #d
        if condition(surface_u, feature_u):
            add(surface_u)
        node = node.next
    return ret 

# ur".." : Raw text in Unicode
text = ur"""
ですからぁ〜、マックではここに「こ」って書かないでください。
必要ない名詞(記号とか)が入っていると誤作動しちゃいます><
"""[1:-1] # <- 最初の改行文字と最後の改行文字を取り除く

ary = mecab_only_content_nouns(text)

for i, itm in enumerate(ary):
    print i + 1, itm