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References: <CALVX-obUsDkCNHgEAxbpFUxBkyeketYECEz3gF69fPeaMC_Vzw@mail.gmail.com>
Date: Sat, 21 Sep 2013 01:25:13 +0200
Subject: Re: Iterate through a list of tuples for processing
From: Vlastimil Brom <vlastimil.brom@gmail.com>
To: python <python-list@python.org>
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2013/9/20 Shyam Parimal Katti <spk265@nyu.edu>:
> I have a list of tuples where the number of rows in the list and the numb=
er
> of columns in tuples of the list will not be constant. i.e.
>
>  ...> i.e.
>
> list_value =3D [(=91name1=92, 1234, =91address1=92 ), (=91name2=92, 5678,=
 =91address2=92),
> (=91name3=92, 1011, =91addre=94ss3=92)]
>
> I need to access each value to check if the value contains a double quote
> and enclose the string containing double quote with double quotes. The
> transformation should return
>
> list_value =3D [(=91name1=92, 1234, =91address1=92 ), (=91name2=92, 5678,=
 =91address2=92),
> (=91name3=92, 1011, =91=94addre=94ss3=94=92)]
>
>  ...>
>
>
> Is there a way to make the code concise using list comprehension?
>
>
> --
> https://mail.python.org/mailman/listinfo/python-list
>

Hi,
would the following do, what you want?

>>> orig_list =3D [('name1', 1234, 'address1' ), ('name2', 5678, 'address2'=
), ('name3', 1011, 'addre"ss3')]
>>> modif_list =3D [['"'+elem+'"' if isinstance(elem, basestring) and '"' i=
n elem else elem for elem in row] for row in orig_list]
>>> modif_list
[['name1', 1234, 'address1'], ['name2', 5678, 'address2'], ['name3',
1011, '"addre"ss3"']]
>>>

I guess, you don't mind changing the inner tuples to lists, but the
original structure could be retained as well:
>>> [tuple(['"'+elem+'"' if isinstance(elem, basestring) and '"' in elem el=
se elem for elem in row]) for row in orig_list]
[('name1', 1234, 'address1'), ('name2', 5678, 'address2'), ('name3',
1011, '"addre"ss3"')]
>>>

Of course, you have to decide, whether the readability/conciseness
suits your needs ...

hth,
   vbr