Different output formats possible via constructor arguments?

[jzohrab]

Hello, thank you very much for your work on this project. I'm using MeCab for a language-learning program, and would like to use this library if possible.

The mecab binary allowed for some arguments to be passed which would affect its output. For example:

$ mecab -F %m\\t%t\\t%h\\n -U %m\\t%t\\t%h\\n -E EOP\\t3\\t7\\n
太郎はこの本を女性に渡した。
太郎	2	44
は	6	16
この	6	68
本	2	38
を	6	13
女性	2	38
に	6	13
渡し	2	31
た	6	25
。	3	7
EOP	3	7

Is there a way to get the same with this python library? I tried some obvious attempts, e.g.

import MeCab
t = MeCab.Tagger('-F %m\\t%t\\t%h\\n -U %m\\t%t\\t%h\\n -E EOP\\t3\\t7\\n -r ./mecabrc_dummy.txt -d ./.venv/lib/python3.11/site-packages/unidic_lite/dicdir')   # also tried single \ instead of \\
sentence = "太郎はこの本を女性に渡した。"
print(t.parse(sentence))

but this still outputs the same as the default Tagger output:

$ python main.py 
太郎	タロー	タロウ	タロウ	名詞-固有名詞-人名-名			1
は	ワ	ハ	は	助詞-係助詞			
この	コノ	コノ	此の	連体詞			0
...
渡し	ワタシ	ワタス	渡す	動詞-一般	五段-サ行	連用形-一般	0
た	タ	タ	た	助動詞	助動詞-タ	終止形-一般	
。			。	補助記号-句点			
EOS

I edited unidic_lite/dicdir/dicrc:

output-format-type = custom

; output custom - new three-column output
node-format-custom = %m\t%t\t%h\n
unk-format-custom  = %m\t%t\t%h\n
bos-format-custom  =
eos-format-custom  = EOP\t3\t7\n

With that, the output was more or less what I expected (the third column is different, but that doesn't matter):

$ python main.py 
太郎	2	1
は	6	1
この	6	1
本	2	1
...
た	6	1
。	3	1
EOP	3	7

I did try with unidic, instead of unidic_lite,

t = MeCab.Tagger('-r ./mecabrc_dummy.txt -d ./.venv/lib/python3.11/site-packages/unidic/dicdir -F %m\\t%t\\t%h\\n -U %m\\t%t\\t%h\\n -E EOP\\t3\\t7\\n')

and got the default unidic output:

太郎	名詞,固有名詞,人名,名,,,タロウ,タロウ,太郎,タロー,太郎,タロー,固,"","","","","","",名,タロウ,タロウ,タロウ,タロウ,"1","","",6252931250790912,22748
は	助詞,係助詞,,,,,ハ,は,は,ワ,は,ワ,和,"","","","","","",係助,ハ,ハ,ハ,ハ,"","動詞%F2@0,名詞%F1,形容詞%F2@-1","",8059703733133824,29321
この	連体詞,,,,,,コノ,此の,この,コノ,この,コノ,和,"","","","","","",相,コノ,コノ,コノ,コノ,"0","","",3547308012741120,12905
...
。	補助記号,句点,,,,,,。,。,,。,,記号,"","","","","","",補助,,,,,"","","",6880571302400,25
EOS

Thank you again!

[polm]

This is not possible due to a long standing issue in MeCab that causes the UniDic config file to take precedence. Your command line version only works because your config (presumably IPAdic) doesn't specify a default format. I made a PR to fix it six years ago but never received any response.

taku910/mecab#38

However, rather than using MeCab's rather arcane format syntax, I suggest you use fugashi's structured Node objects to create formatted node output - it should be much easier.

https://github.com/polm/fugashi