How to go from token list-> string again

[Sania]

I have a token list but I want to change all of them back into
strings.
Is this possible? I have been searching but I can't really find
anything, or maybe I just don't understand it.

Thanks,
Sania

[Alex Rudnick]

Hey Sania,

If you just have a list of strings, consider:

mylistofstrings = ["foo", "bar", "baz"]
joinedtogether = " ".join(mylistofstrings)

Now joinedtogether is the string "foo bar baz".

If you have a list of tuples of strings (say where the second element
is a pos tag), then that's a little more complicated, but just go
through the list and take out the first element of each tuple.

taggedwords = [("the", "DT"), ("dog", "NN")]
words = [word for (word,tag) in taggedwords]

Then just do a join on the variable words.

In the long run, not sure this is the best place to ask basic Python
questions :)

Cheers,

--
-- alexr

[Sania]

Thanks :)

On Apr 13, 2:51 pm, Alex Rudnick <alex.rudn...@gmail.com> wrote:
> Hey Sania,
>
> If you just have a list of strings, consider:
>
> mylistofstrings = ["foo", "bar", "baz"]
> joinedtogether = " ".join(mylistofstrings)
>
> Now joinedtogether is the string "foo bar baz".
>
> If you have a list of tuples of strings (say where the second element
> is a pos tag), then that's a little more complicated, but just go
> through the list and take out the first element of each tuple.
>
> taggedwords = [("the", "DT"), ("dog", "NN")]
> words = [word for (word,tag) in taggedwords]
>
> Then just do a join on the variable words.
>
> In the long run, not sure this is the best place to ask basic Python
> questions :)
>

[Alex Rudnick]

Francisco,

I think most of the time, that won't work in Python :) Unless you've
built a Java interpreter into your copy of Python...

On Sat, Apr 14, 2012 at 8:27 AM, FranciscoMXCA
<francisc...@gmail.com> wrote:
>
> Try yourList.toArray() as in
> http://www.exampledepot.com/egs/java.util/coll_GetArrayFromVector.html

--
-- alexr

[Erick Fonseca]

I don't think there is a straightforward solution to this, but calling
" ".join() will leave you with all tokens, including periods and
commas, with whitespaces between them.

If you want the string in a more readable format, you could call
s.replace(' ,', ',')
s.replace(' .', '.')

to eliminate spaces before whatever tokens you want. Or maybe use a
regular expression.

Cheers,
Erick

On Apr 13, 3:51 pm, Alex Rudnick <alex.rudn...@gmail.com> wrote:
> Hey Sania,
>
> If you just have a list of strings, consider:
>
> mylistofstrings = ["foo", "bar", "baz"]
> joinedtogether = " ".join(mylistofstrings)
>
> Now joinedtogether is the string "foo bar baz".
>
> If you have a list of tuples of strings (say where the second element
> is a pos tag), then that's a little more complicated, but just go
> through the list and take out the first element of each tuple.
>
> taggedwords = [("the", "DT"), ("dog", "NN")]
> words = [word for (word,tag) in taggedwords]
>
> Then just do a join on the variable words.
>
> In the long run, not sure this is the best place to ask basic Python
> questions :)
>

[deepti patil]

Hi,

If we have a list of list say :

sample = [[ 'I' ,'am', 'studying','Physics'],['I','am', 'going','to','the','wedding']]

The output should be :

output = [[I am studying Physics],[I am going to the wedding]]

In this case I was trying to join sentences using " ".join() but was not able to. How to proceed in such cases?

[Jordi Carrera]

Hey Deepti,

I think what you need is list comprehension, like this:

>>> sample = [[ 'I' ,'am', 'studying','Physics'],['I','am', 'going','to','the','wedding']]

>>> output = [' '.join(x) for x in sample]
>>> print output
['I am studying Physics', 'I am going to the wedding']

However, notice the final output is a list of strings (vs. the input, which was a list of lists of strings), so it's not exactly the same as what you provided as the ideal output:

[[I am studying Physics],[I am going to the wedding]]

However, the latter does not actually seem valid Python code :) so I assume you meant the output to be as shown above.

Hope this helps!

Jordi

[deepti patil]

Thanks a lot!!

Thanks & Regards,

Deepti R. Patil

+91-9654395874

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