[BangPypers] How should I do it?

[Dhananjay Nene]

On Fri, Jan 15, 2010 at 12:01 PM, Eknath Venkataramani <
eknath.iyer at gmail.com> wrote:

> I have a txt file in the following format:
> [code]
> "confident" => {
>  count => 4,
>  trans => {
>     "ashahvasahta" => 0.74918568,
>    "atahmavaishahvaasa" => 0.09095465,
>    "pahraaram\.nbha" => 0.06990729,
>         "mailatae" => 0.02856427,
>           "utanai" => 0.01929341,
>             "anaa" => 0.01578552,
>         "uthaanae" => 0.01403157,
>         "jaitanae" => 0.01227762,
>    },
> },
> "consumers" => {
>  count => 4,
>  trans => {
>    "upabhaokahtaa" => 0.75144362,
>    "upabhaokahtaaom\.n" => 0.12980166,
>    "sauda\�\�\�dha" => 0.11875471,
>    },
> },
> "a" => {
>  count => 1164,
>  trans => {
>              "eka" => 0.14900491,
>           "kaisai" => 0.08834675,
>             "haai" => 0.06774697,
>             "kaoi" => 0.05394308,
>              "kai" => 0.04981982,
>         "\(none\)" => 0.04400085,
>              "kaa" => 0.03726579,
>              "kae" => 0.03446450,
>    },
> },
> [/code]
>
> and I need to extract "confident" , "ashahvasahta" from the first
> record, "consumers",  "upabhaokahtaa" from the second record...
> i.e. "word in english" and the "first word in the probable-translations"
>
> Thanks is advance
> Eknath
> _______________________________________________
> BangPypers mailing list
> BangPypers at python.org
> http://mail.python.org/mailman/listinfo/bangpypers
>

Since I hadn't had a chance to write a recursive descent parser, took this
opportunity to do a bit of an exercise.
I have used a parser called pyparsing.

---------- Begin Code ----------
# coding=utf-8
from pyparsing import *
import pprint
import sys

data = '''
"confident" => {
   count => 4,
   trans => {
     "ashahvasahta" => 0.74918568,
     "atahmavaishahvaasa" => 0.09095465,
     "pahraaram\.nbha" => 0.06990729,
     "mailatae" => 0.02856427,
     "utanai" => 0.01929341,
     "anaa" => 0.01578552,
     "uthaanae" => 0.01403157,
     "jaitanae" => 0.01227762,
   },
},
"consumers" => {
 count => 4,
 trans => {
   "upabhaokahtaa" => 0.75144362,
   "upabhaokahtaaom\.n" => 0.12980166,
   "sauda\�\�\�dha" => 0.11875471,
   },
},
"a" => {
 count => 1164,
 trans => {
             "eka" => 0.14900491,
          "kaisai" => 0.08834675,
            "haai" => 0.06774697,
            "kaoi" => 0.05394308,
             "kai" => 0.04981982,
        "\(none\)" => 0.04400085,
             "kaa" => 0.03726579,
             "kae" => 0.03446450,
   },
}
'''

# Setup pyparsing tokens
dct = Forward()
pair_op = Literal("=>")
comma = Literal(",").suppress()
beg_brace = Literal("{").suppress()
end_brace = Literal("}").suppress()
num = Word("0123456789.")
key = (Word(alphas + nums) ^ quotedString).setResultsName("key")
val = (num ^ dct).setResultsName("value")
key_value_pair = Group(key + pair_op.suppress() + val)
key_value_pair_list = delimitedList(key_value_pair)
dct << Group(beg_brace + key_value_pair_list + Optional(comma) + end_brace)

# parse data
parsed = key_value_pair_list.parseString(data)

# function to extract ie. form a python datastructure
def extract(result):
        if 'key' in result.keys() :
            if isinstance(result.value,ParseResults) :
                return ( result.key,  extract(result.value) )
            else :
                return ( result.key,  result.value )
        else :
            return(dict(extract(elem) for elem in result))

# extract
extracted = extract(parsed)

# print extracted data
pprint.pprint(extracted, sys.stdout)

# print the english word and first translated word

print "\n\n============\nTranslations\n============\n"
print dict(
        (english,
         reduce(lambda x,y : (y[0],float(y[1])) if float(y[1]) > x[1] else x
,
                translations['trans'].items(),
                ('',0.0))[0]
        ) for english,translations in extracted.items()
    )

---------- End Code ----------

Dhananjay

-- 
--------------------------------------------------------
blog: http://blog.dhananjaynene.com
twitter: http://twitter.com/dnene http://twitter.com/_pythonic