Character Sequence Generation

[Jeff Schwab]

What's the best way to generate a sequence of characters in Python? I'm
looking for something like this Perl code: 'a' .. 'z' .

[mensanator@aol.com]

Re: Character Sequence Generation


Jeff Schwab wrote:[color=blue]
> What's the best way to generate a sequence of characters in Python? I'm
> looking for something like this Perl code: 'a' .. 'z' .[/color]
[color=blue][color=green][color=darkred]
>>> import string[/color][/color][/color]
[color=blue][color=green][color=darkred]
>>> print string.ascii_lo wercase[/color][/color][/color]
abcdefghijklmno pqrstuvwxyz


Others:

ascii_letters = 'abcdefghijklmn opqrstuvwxyzABC DEFGHIJKLMNOPQR STUVWXYZ'
ascii_lowercase = 'abcdefghijklmn opqrstuvwxyz'
ascii_uppercase = 'ABCDEFGHIJKLMN OPQRSTUVWXYZ'
digits = '0123456789'
hexdigits = '0123456789abcd efABCDEF'
letters =
'ABCDEFGHIJKLMN OPQRSTUVWXYZabc defghijklmnopqr stuv...\xcd\xce ...
lowercase =
'abcdefghijklmn opqrstuvwxyz\x8 3\x9a\x9c\x9e\x aa\xb5\xba\xd.. .
octdigits = '01234567'
printable =
'0123456789abcd efghijklmnopqrs tuvwxyzABCDEFGH IJKLMNOPQRSTU.. .
punctuation = '!"#$%&\'()*+ ,-./:;<=>?@[\\]^_`{|}~'
uppercase =
'ABCDEFGHIJKLMN OPQRSTUVWXYZ\x8 a\x8c\x8e\x9f\x c0\xc1\xc2\xc.. .
whitespace = '\t\n\x0b\x0c\r '

[Jeff Schwab]

Re: Character Sequence Generation

mensanator@aol. com wrote:[color=blue]
> Jeff Schwab wrote:
>[color=green]
>>What's the best way to generate a sequence of characters in Python? I'm
>>looking for something like this Perl code: 'a' .. 'z' .[/color]
>
>[color=green][color=darkred]
>>>>import string[/color][/color]
>
>[color=green][color=darkred]
>>>>print string.ascii_lo wercase[/color][/color]
>
> abcdefghijklmno pqrstuvwxyz[/color]

Thanks. Is there a good way to generate the characters dynamically?

[Devan L]

Re: Character Sequence Generation


Jeff Schwab wrote:[color=blue]
> mensanator@aol. com wrote:[color=green]
> > Jeff Schwab wrote:
> >[color=darkred]
> >>What's the best way to generate a sequence of characters in Python? I'm
> >>looking for something like this Perl code: 'a' .. 'z' .[/color]
> >
> >[color=darkred]
> >>>>import string[/color]
> >
> >[color=darkred]
> >>>>print string.ascii_lo wercase[/color]
> >
> > abcdefghijklmno pqrstuvwxyz[/color]
>
> Thanks. Is there a good way to generate the characters dynamically?[/color]

''.join([chr(i) for i in range(97,123)])

[Pedro Werneck]

Re: Character Sequence Generation

On Thu, 22 Sep 2005 23:26:58 -0400
Jeff Schwab <jeffrey.schwab @rcn.com> wrote:
[color=blue]
> What's the best way to generate a sequence of characters in Python?
> I'm looking for something like this Perl code: 'a' .. 'z' .[/color]

If you want arbitrary sequences, you may use something like:

[color=blue][color=green][color=darkred]
>>> [chr(x) for x in xrange(ord('a') , ord('z') + 1)][/color][/color][/color]
['a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n',
'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z']
[color=blue][color=green][color=darkred]
>>> [chr(x) for x in xrange(ord('d') , ord('p') + 1)][/color][/color][/color]
['d', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p']
[color=blue][color=green][color=darkred]
>>> [chr(x) for x in xrange(ord('A') , ord('Z') + 1)][/color][/color][/color]
['A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N',
'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z']

etc...

--
Pedro Werneck

[Peter Otten]

Re: Character Sequence Generation

Jeff Schwab wrote:
[color=blue]
> What's the best way to generate a sequence of characters in Python? I'm
> looking for something like this Perl code: 'a' .. 'z' .[/color]
[color=blue][color=green][color=darkred]
>>> import re
>>> def char_set(a_z, all_chars="".jo in(map(chr, range(256)))):[/color][/color][/color]
.... return re.compile("[%s]" % a_z).findall(al l_chars)
....[color=blue][color=green][color=darkred]
>>> for c in char_set("a-f0-9"): print c,[/color][/color][/color]
....
0 1 2 3 4 5 6 7 8 9 a b c d e f[color=blue][color=green][color=darkred]
>>> for c in char_set("\s"): print repr(c),[/color][/color][/color]
....
'\t' '\n' '\x0b' '\x0c' '\r' ' '

Peter

[Jeff Schwab]

Re: Character Sequence Generation

Pedro Werneck wrote:[color=blue]
> On Thu, 22 Sep 2005 23:26:58 -0400
> Jeff Schwab <jeffrey.schwab @rcn.com> wrote:
>
>[color=green]
>>What's the best way to generate a sequence of characters in Python?
>>I'm looking for something like this Perl code: 'a' .. 'z' .[/color]
>
>
> If you want arbitrary sequences, you may use something like:
>
>
>[color=green][color=darkred]
>>>>[chr(x) for x in xrange(ord('a') , ord('z') + 1)][/color][/color]
>
> ['a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n',
> 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z']
>
>[color=green][color=darkred]
>>>>[chr(x) for x in xrange(ord('d') , ord('p') + 1)][/color][/color]
>
> ['d', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p']
>
>[color=green][color=darkred]
>>>>[chr(x) for x in xrange(ord('A') , ord('Z') + 1)][/color][/color]
>
> ['A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N',
> 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z']
>
> etc...
>[/color]

Thanks, that's exactly what I want!

[skip@pobox.com]

Re: Sniffing Text Files


David> I realize CSV module has a sniffer but it is something that is
David> limited more or less to delimited files.

Sure. How about:

def sniff(fname):
if open(fname).rea d(4) == "<xml":
return "xml"
else:
# assume csv - use its sniffer to generate a dialect
return d

Of course, as the number of file formats grows, you'll need to expand the
logic. You can also run the file(1) command and see what it says. I seem
to recall someone asking about the equivalent to file(1) implemented in
Python awhile back.

--
Skip Montanaro
Katrina Benefit Concerts: http://www.musi-cal.com/katrina
skip@pobox.com