What is a most simple expression for splitting a CSV line with "-protected fields?
s='"123","a,b,\ "c\"",5.640 '
s='"123","a,b,\ "c\"",5.640 '
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Re: split CSV fields
s.split(',');
robert wrote:What is a most simple expression for splitting a CSV line with "-protected fields?
>
s='"123","a,b,\ "c\"",5.640 ' -
Re: split CSV fields
robert wrote:
import csvWhat is a most simple expression for splitting a CSV line
with "-protected fields?
>
s='"123","a,b,\ "c\"",5.640 '
the preferred way is to read the file using that module. if you insist
on processing a single line, you can do
cols = list(csv.reader ([string]))
</F>
Comment
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Re: split CSV fields
robert wrote:
Use the csv-module. It should have a dialect for this, albeit I'm not 100%What is a most simple expression for splitting a CSV line with "-protected
fields?
>
s='"123","a,b,\ "c\"",5.640 '
sure if the escaping of the " is done properly from csv POV. Might be that
it requires excel-standard.
Diez
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Re: split CSV fields
robert wrote:
What is a most simple expression for splitting a CSV line with "-protected
fields?
>
s='"123","a,b,\ "c\"",5.640 '.... escapechar = "\\">>import csv
>>class mydialect(csv.e xcel):
....['123', 'a,b,"c"', '5.640']>>csv.reader(['"123","a,b,\\" c\\"",5.640'], dialect=mydiale ct).next()
Peter
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Re: split CSV fields
Fredrik Lundh wrote:Python 2.5 (r25:51908, Sep 19 2006, 09:52:17) [MSC v.1310 32 bitrobert wrote:
>>What is a most simple expression for splitting a CSV line
with "-protected fields?
s='"123","a,b,\ "c\"",5.640 '
import csv
>
the preferred way is to read the file using that module. if you insist
on processing a single line, you can do
>
cols = list(csv.reader ([string]))
>
</F>
(Intel)] on win32
| >>import csv
| >>s='"123","a,b ,\"c\"",5.640 '
| >>cols = list(csv.reader ([s]))
| >>cols
[['123', 'a,b,c""', '5.640']]
# maybe we need a bit more:
| >>cols = list(csv.reader ([s]))[0]
| >>cols
['123', 'a,b,c""', '5.640']
I'd guess that the OP is expecting 'a,b,"c"' for the second field.
Twiddling with the knobs doesn't appear to help:
| >>list(csv.read er([s], escapechar='\\' ))[0]
['123', 'a,b,c""', '5.640']
| >>list(csv.read er([s], escapechar='\\' , doublequote=Fal se))[0]
['123', 'a,b,c""', '5.640']
Looks like a bug to me; AFAICT from the docs, the last attempt should
have worked.
Cheers,
John
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Re: split CSV fields
John Machin wrote:Given Peter Otten's post, looks likeFredrik Lundh wrote:>robert wrote:
import csvWhat is a most simple expression for splitting a CSV line
with "-protected fields?
>
s='"123","a,b,\ "c\"",5.640 '
the preferred way is to read the file using that module. if you insist
on processing a single line, you can do
cols = list(csv.reader ([string]))
</F>
Python 2.5 (r25:51908, Sep 19 2006, 09:52:17) [MSC v.1310 32 bit
(Intel)] on win32
| >>import csv
| >>s='"123","a,b ,\"c\"",5.640 '
| >>cols = list(csv.reader ([s]))
| >>cols
[['123', 'a,b,c""', '5.640']]
# maybe we need a bit more:
| >>cols = list(csv.reader ([s]))[0]
| >>cols
['123', 'a,b,c""', '5.640']
>
I'd guess that the OP is expecting 'a,b,"c"' for the second field.
>
Twiddling with the knobs doesn't appear to help:
>
| >>list(csv.read er([s], escapechar='\\' ))[0]
['123', 'a,b,c""', '5.640']
| >>list(csv.read er([s], escapechar='\\' , doublequote=Fal se))[0]
['123', 'a,b,c""', '5.640']
>
Looks like a bug to me; AFAICT from the docs, the last attempt should
have worked.
(1) there's a bug in the "fmtparam" mechanism -- it's ignoring the
escapechar in my first twiddle, which should give the same result as
Peter's.
(2)
| >>csv.excel.dou blequote
True
According to my reading of the docs:
"""
doublequote
Controls how instances of quotechar appearing inside a field should be
themselves be quoted. When True, the character is doubled. When False,
the escapechar is used as a prefix to the quotechar. It defaults to
True.
"""
Peter's example should not have worked.
Comment
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Re: split CSV fields
John Machin wrote:
the documentation also mentions a "quoting" parameter that "controlsGiven Peter Otten's post, looks like
(1) there's a bug in the "fmtparam" mechanism -- it's ignoring the
escapechar in my first twiddle, which should give the same result as
Peter's.
(2)
| >>csv.excel.dou blequote
True
According to my reading of the docs:
"""
doublequote
Controls how instances of quotechar appearing inside a field should be
themselves be quoted. When True, the character is doubled. When False,
the escapechar is used as a prefix to the quotechar. It defaults to
True.
"""
Peter's example should not have worked.
when quotes should be generated by the writer and recognised by the
reader.". not sure how that changes things.
anyway, it's either unclear documentation or a bug in the code. better
submit a bug report so someone can fix one of them.
</F>
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Re: split CSV fields
John Machin wrote:Doh. The OP's string was a raw string. I need some sleep.John Machin wrote:>Fredrik Lundh wrote:Python 2.5 (r25:51908, Sep 19 2006, 09:52:17) [MSC v.1310 32 bitrobert wrote:
>
What is a most simple expression for splitting a CSV line
with "-protected fields?
s='"123","a,b,\ "c\"",5.640 '
>
import csv
>
the preferred way is to read the file using that module. if you insist
on processing a single line, you can do
>
cols = list(csv.reader ([string]))
>
</F>
(Intel)] on win32
| >>import csv
| >>s='"123","a,b ,\"c\"",5.640 '
| >>cols = list(csv.reader ([s]))
| >>cols
[['123', 'a,b,c""', '5.640']]
# maybe we need a bit more:
| >>cols = list(csv.reader ([s]))[0]
| >>cols
['123', 'a,b,c""', '5.640']
I'd guess that the OP is expecting 'a,b,"c"' for the second field.
Twiddling with the knobs doesn't appear to help:
| >>list(csv.read er([s], escapechar='\\' ))[0]
['123', 'a,b,c""', '5.640']
| >>list(csv.read er([s], escapechar='\\' , doublequote=Fal se))[0]
['123', 'a,b,c""', '5.640']
Looks like a bug to me; AFAICT from the docs, the last attempt should
have worked.
Given Peter Otten's post, looks like
(1) there's a bug in the "fmtparam" mechanism -- it's ignoring the
escapechar in my first twiddle, which should give the same result as
Peter's.
(2)
| >>csv.excel.dou blequote
True
According to my reading of the docs:
"""
doublequote
Controls how instances of quotechar appearing inside a field should be
themselves be quoted. When True, the character is doubled. When False,
the escapechar is used as a prefix to the quotechar. It defaults to
True.
"""
Peter's example should not have worked.
Scrap bug #1!
| >>s=r'"123","a, b,\"c\"",5.640 '
| >>list(csv.read er([s]))[0]
['123', 'a,b,\\c\\""', '5.640']
# What's that???
| >>list(csv.read er([s], escapechar='\\' ))[0]
['123', 'a,b,"c"', '5.640']
| >>list(csv.read er([s], escapechar='\\' , doublequote=Fal se))[0]
['123', 'a,b,"c"', '5.640']
And there's still the problem with doublequote ....
Goodnight ...
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Re: split CSV fields
John Machin wrote:
Note how I fixed the input:| >>s='"123","a,b ,\"c\"",5.640 '
'"123","a,b,"c" ",5.640'>>'"123","a,b,\ "c\"",5.640 '
'"123","a,b,\\" c\\"",5.640'>>'"123","a,b,\ \"c\\"",5.64 0'
Peter
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Re: split CSV fields
Fredrik Lundh wrote:Hi Fredrik, I read that carefully -- "quoting" appears to have noJohn Machin wrote:
>>Given Peter Otten's post, looks like
(1) there's a bug in the "fmtparam" mechanism -- it's ignoring the
escapechar in my first twiddle, which should give the same result as
Peter's.
(2)
| >>csv.excel.dou blequote
True
According to my reading of the docs:
"""
doublequote
Controls how instances of quotechar appearing inside a field should be
themselves be quoted. When True, the character is doubled. When False,
the escapechar is used as a prefix to the quotechar. It defaults to
True.
"""
Peter's example should not have worked.
the documentation also mentions a "quoting" parameter that "controls
when quotes should be generated by the writer and recognised by the
reader.". not sure how that changes things.
effect in this situation.
Tomorrow :-)>
anyway, it's either unclear documentation or a bug in the code. better
submit a bug report so someone can fix one of them.
Cheers,
John
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