A quirk/gotcha of for i, x in enumerate(seq) when seq is empty
This week I was slightly surprised by a behaviour that I've not considered before. I've long used for i, x in enumerate(seq): # do stuff as a standard looping-with-index construct. In Python for loops don't create a scope, so the loop variables are available afterward. I've sometimes used this to print or return a record count e.g. for i, x in enumerate(seq): # do stuff print 'Processed %i records' % i+1 However as I found out, if seq is empty then i and x are never created. The above code will raise NameError. So if a record count is needed, and the loop is not guaranteed to execute the following seems more correct: i = 0 for x in seq: # do stuff i += 1 print 'Processed %i records' % i Just thought it worth mentioning, curious to hear other options/ improvements/corrections. -- http://mail.python.org/mailman/listinfo/python-list
Benchmarking stripping of Unicode characters which are invalid XML
Last week I was surprised to discover that there are Unicode characters that
aren't valid in an XML document. That is regardless of escaping (e.g. �)
and unicode encoding (e.g. UTF-8) - not every Unicode string can be stored in
XML. The valid characters are (as of XML 1.0) #x9 | #xA | #xD | [#x20-#xD7FF] |
[#xE000-#xFFFD] | [#x1-#x10]. Others such as #x13 must be stripped,
replaced or placed inside a wrapper such as base64.
I didn't find an existing function to strip these so I wrote some and
benchmarked them. I'd be interested for thoughts, suggestions and improvements.
regsub_p2 was the fastest on a string containing mostly printable-ascii.
regsub_p1 0.422097921371 True
regsub_p2 0.353546857834 True
regsub_p3 0.697242021561 True
regsub_p4 0.677567005157 True
genexp_p1 6.43633103371 True
genexp_p2 6.43329787254 True
genexp_p3 6.80837488174 True
genexp_p4 6.81470417976 True
filter_p1 7.2116046 True
filter_p2 7.46805095673 True
filter_p3 7.37018704414 True
filter_p4 7.03261303902 True
genexp_f1 12.8470640182 True
genexp_f2 5.43630099297 True
genexp_f3 4.9708840847 True
genexp_f4 12.2384109497 True
genexp_f5 6.95861411095 True
genexp_f6 4.7168610096 True
genexp_f7 20.2065701485 True
genexp_f8 21.1112251282 True
Regards, Alex
#!/usr/bin/python
# Valid XML 1.0 characters are
# #x9 | #xA | #xD | [#x20-#xD7FF] | [#xE000-#xFFFD] | [#x1-#x10]
# http://www.w3.org/TR/2008/PER-xml-20080205/#charsets
#
# Before passing an arbitrary unicode string to an XML encoder invalid
characters
# must be stripped or replaced. Escaping them doesn't help - they're simply not
# allowed in a well formed XML 1.0 document.
# The following script banchmarks several functions that strip them
import re
import string
import timeit
p1 = re.compile(u'[^\x09\x0A\x0D\u0020-\uD7FF'
u'\uE000-\uFFFD\U0001-\U0010]', re.U)
p2 = re.compile(u'[^\u0020-\uD7FF\x09\x0A\x0D'
u'\uE000-\uFFFD\U0001-\U0010]', re.U)
p3 = re.compile(p1.pattern + u'+', re.U)
p4 = re.compile(p2.pattern + u'+', re.U)
def regsub_p1(s): return p1.sub(u'', s)
def regsub_p2(s): return p2.sub(u'', s)
def regsub_p3(s): return p3.sub(u'', s)
def regsub_p4(s): return p4.sub(u'', s)
def genexp_p1(s): return u''.join(c for c in s if not p1.match(c))
def genexp_p2(s): return u''.join(c for c in s if not p2.match(c))
def genexp_p3(s): return u''.join(c for c in s if not p3.match(c))
def genexp_p4(s): return u''.join(c for c in s if not p4.match(c))
def filter_p1(s): return u''.join(filter(lambda c: not p1.match(c), s))
def filter_p2(s): return u''.join(filter(lambda c: not p2.match(c), s))
def filter_p3(s): return u''.join(filter(lambda c: not p3.match(c), s))
def filter_p4(s): return u''.join(filter(lambda c: not p4.match(c), s))
def f1(c):
i = ord(c)
return (i in set([0x09, 0x0A, 0x0D]) or 0x0020 <= i <= 0xD7FF
or 0xE000 <= i <= 0xFFFD or 0x0001 <= i <= 0x0010)
def f2(c):
i = ord(c)
return (0x0020 <= i <= 0xD7FF or i in set([0x09, 0x0A, 0x0D])
or 0xE000 <= i <= 0xFFFD or 0x0001 <= i <= 0x0010)
def f3(c):
return (u'\u0020' <= c <= u'\uD7FF' or c in set([u'\x09', u'\x0A', u'\x0D'])
or u'\uE000' <= c <= u'\uFFFD' or u'\U0001' <= c <=
u'\U0010')
def f4(c):
return (c in set([u'\x09', u'\x0A', u'\x0D']) or u'\u0020' <= c <= u'\uD7FF'
or u'\uE000' <= c <= u'\uFFFD' or u'\U0001' <= c <=
u'\U0010')
def f5(c):
return (c == u'\x09' or c == u'\x0A' or c == u'\x0D' or u'\u0020' <= c <=
u'\uD7FF'
or u'\uE000' <= c <= u'\uFFFD' or u'\U0001' <= c <=
u'\U0010')
def f6(c):
return (u'\u0020' <= c <= u'\uD7FF' or c == u'\x09' or c == u'\x0A' or c ==
u'\x0D'
or u'\uE000' <= c <= u'\uFFFD' or u'\U0001' <= c <=
u'\U0010')
every_8bit = u''.join(unichr(i) for i in range(256))
valid_8bit = u''.join(c for c in every_8bit if f1(c))
invalid_8bit = u''.join(c for c in every_8bit if not f1(c))
invalid_8bit_iso88591 = invalid_8bit.encode('iso-8859-1')
translator = string.maketrans(invalid_8bit_iso88591,
'\x00' * len(invalid_8bit_iso88591))
def f7(c):
return ((c <= u'\xff' and ord(string.translate(c.encode('iso-8859-1'),
translator)))
or u'\uE000' <= c <= u'\uFFFD' or u'\U0001' <= c <=
u'\U0010')
def f8(c):
return ((c <= u'\xff' and string.translate(c.encode('iso-8859-1'), None,
invalid_8bit_iso88591))
or u'\uE000' <= c <= u'\uFFFD' or u'\U0001' <= c <=
u'\U0010')
def genexp_f1(s): return u''.join(c for c in s if f1(c))
def genexp_f2(s): return u''.join(c for c in s if f2(c))
def genexp_f3(s): return u''.join(c for c in s if f3(c))
def genexp_f4(s): return u''.join(c for c in s if f4(c))
def genexp_f5(s): return u''.join(c for c in s if f5(c))
def genexp_f6(s): return u''.join(c for c in s if f6(c))
def genexp_f7(s): return u''.join(c for c in s if f7(c))
def genexp_f8(s): return u''.joi
Re: trac.util
On Apr 11, 9:52 pm, cerr wrote: > Hi, > > I want to install some python driver on my system that requires trac.util > (from Image.py) but I can't find that anywhere, any suggestions, anyone? > > Thank you very much, any help is appreciated! > > Error: > File "/root/weewx/bin/Image.py", line 32, in > from trac.util import escape > ImportError: No module named trac.util Trac is a bug tracker/wiki. Installation instruction are at http://trac.edgewall.org/wiki/TracDownload or you can probably through your operating system's package manager. Regards, Alex -- http://mail.python.org/mailman/listinfo/python-list
Re: *.sdf database access
On Apr 19, 9:18 pm, Page3D wrote: > Hi, I am trying to connect and access data in a *.sdf file on Win7 > system using Python 2.7. I have three questions: > > 1. What python module should I use? I have looked at sqlite3 and > pyodbc. However, I can seem to get the connection to the database file > setup properly. I assume you mean SQL Server Compact by *.sdf. However please note that there are several several file formats matching SDF http://en.wikipedia.org/wiki/SDF#Computing and explicit is better than implicit. The sqlite3 module won't help - that's for sqlite files, which an entirely different file format. Wikpedia says of SQL Server Compact "An ODBC driver for SQL CE does not exist, and one is not planned either. Native applications may use SQL CE via OLE DB" http://en.wikipedia.org/wiki/SQL_Server_Compact. I believe the adodbapi module, part of PyWin32 http://sourceforge.net/projects/pywin32/files/ can connect over OLE DB. > 2. How can I determine the appropriate connection string? I have > opened database file in Visual Studio and can see the tables. I don't > understand where to find the connection string in Visual Studio. These look promising http://www.connectionstrings.com/sql-server-2005-ce > 3. Assuming a module from (1) above, does anyone have a code snippet > for connecting to the database and then accessing a varbinary (image) > in one of the tables of the databese? Pass, I'm afraid Regards, Alex -- http://mail.python.org/mailman/listinfo/python-list
Re: subclass urllib2
On Feb 28, 6:53 pm, monkeys paw wrote: > I'm trying to subclass urllib2 in order to mask the > version attribute. Here's what i'm using: > > import urllib2 > > class myURL(urllib2): > def __init__(self): > urllib2.__init__(self) > self.version = 'firefox' > > I get this> > Traceback (most recent call last): > File "", line 1, in > TypeError: Error when calling the metaclass bases > module.__init__() takes at most 2 arguments (3 given) > > I don't see where i am supplying 3 arguments. What am i > missing? urllib2 is a module, not a class, so you can't subclass it. You could subclass one of the classes inside urllib2, such as urllib2.BaseHandler. Whether you want to depends on what your want to achieve. -- http://mail.python.org/mailman/listinfo/python-list
下载 below Download, in python.org site menu
On the English version of http://python.org I'm seeing 下载 as a menu item between Download and Community. AFAICT it's Simplified Chinese for 'download'. Is it's appearance intentional, or a leak through from a translation of the entire page? Regards, Alex PS Tested with 10.0.648.114 (75702) and Firefox 3.6.14 on Ubuntu 10.10/ en_GB locale. -- http://mail.python.org/mailman/listinfo/python-list
Re: error in exception syntax
On Mar 9, 6:12 pm, "Aaron Gray" wrote: > On Windows I have installed Python 3.2 and PyOpenGL-3.0.1 and am getting the > following error :- > > File "c:\Python32\lib\site-packages\OpenGL\platform\win32.py", line 13 > except OSError, err: > ^ > > It works okay on my Linux machine running Python 2.6.2. Python 3.x is a different beast to Python 2.x. It has a number of backward incompatible changes, including the try/except syntax. Install the latest Python 2.x (Python 2.7) on your Windows machine and use that. Then read http://docs.python.org/release/3.2/whatsnew/3.0.html Regards, Alex -- http://mail.python.org/mailman/listinfo/python-list
Re: argparse and filetypes
On Mar 22, 2:06 pm, Bradley Hintze
wrote:
> I just started with argparse. I want to simply check the extension of
> the file that the user passes to the program. I get a ''file' object
> has no attribute 'rfind'' error when I use
> os.path.splitext(args.infile). Here is my code.
>
> import argparse, sys, os
>
> des = 'Get restraint definitions from probe.'
> parser = argparse.ArgumentParser(description=des)
> parser.add_argument('infile', nargs='?', type=argparse.FileType('r'))
> # parser.add_argument('outfile', nargs='?', type=argparse.FileType('w'),
> # default=sys.stdout)
>
> args = parser.parse_args()
> # print args.infile.readlines()
> print basename, extension = os.path.splitext(args.infile)
Because you specified type=argparse.FileType('r') argparse has created
args.infile as a file object (e.g. open('/some/path/data.dat', 'r')),
not as a string containing the path. So type(args.infile) ==
type(file) and args.infile.readlines() returns the contents of that
file.
If you wish to check the file extension of the path in question I
suggest you remove type=argparse.FileType('r'), argparse will create
args.infile as a string containing that path. To open the file call
open(args.infile, 'r'), this will return the file object.
--
http://mail.python.org/mailman/listinfo/python-list
Re: argparse and filetypes
On Mar 22, 2:06 pm, Bradley Hintze wrote: > Hi, > > I just started with argparse. I want to simply check the extension of > the file that the user passes to the program. I get a ''file' object > has no attribute 'rfind'' error when I use > os.path.splitext(args.infile). Addendum, some file objects have a name attribute (which I hadn't noticed until today): file.name If the file object was created using open(), the name of the file. Otherwise, some string that indicates the source of the file object, of the form <...>. This is a read-only attribute and may not be present on all file-like objects. http://docs.python.org/library/stdtypes.html#file-objects -- http://mail.python.org/mailman/listinfo/python-list
Re: file print extra spaces
On Mar 23, 1:33 am, monkeys paw wrote:
> When i open a file in python, and then print the
> contents line by line, the printout has an extra blank
> line between each printed line (shown below):
>
> >>> f=open('authors.py')
> >>> i=0
> >>> for line in f:
> print(line)
> i=i+1
> if i > 14:
> break
>
> author_list = {
>
> '829337' : {
>
> 'author_name' : 'Carter, John',
>
> 'count' : 49,
>
> 'c2' : '0.102040816326531',
>
> How can i print the file out without having an extra newline between
> printed lines?
>
> Thanks for the help all.
What you are seeing is 1 newline from the original file, and a second
newline from the print() function. To resolve this use either
print(line, end='') or sys.stdout.write(line).
Regards, Alex
--
http://mail.python.org/mailman/listinfo/python-list
Re: Validating Command Line Options
On Mar 23, 3:20 pm, T wrote: > Thanks! argparse is definitely what I need..unfortunately I'm running > 2.6 now, so I'll need to upgrade to 2.7 and hope that none of my other > scripts break. Argparse was a third-party module before it became part of the std- lib. You may find it easier to use this version: http://pypi.python.org/pypi/argparse/ -- http://mail.python.org/mailman/listinfo/python-list
Re: Inconsistency with split() - Script, OS, or Package Problem?
(Direct reply to me, reposted on Jame's behalf) Hi Alex, On Mon, May 9, 2011 at 3:21 PM, Alex Willmer wrote: > On May 9, 8:10 pm, James Wright wrote: >> Hello Ian, >> >> It does indeed to seem that way. However the script works just fine >> on other machines, with the same input file. > > How sure of that are you? Post md5sums of the script and the input > file on a working machine and a non-working (4 md5sums total). > > Does the script use an non-stdlib modules? Check the md5sum of those > too. > > Are the platforms/python versions the same? Post the uname and python - > v from each. > > Can you post the script and the file online for us? Do so. > > Regards, Alex > The md5sums match (great idea by the way, I hadn't thought of that). What do you mean by using a non-stdlib module? I am not using any import statements, if that is what you are referring to. As for kernel and Python versions, I have updated both in case this was a bug - they no longer match across the machines I am testing on. The script consistently works with the machines that it always has been working with. The script continues to not work on the new VMWare installs (but does in new VirtualBox installs - odd). I can post the script (attached), but am not so certain that is at fault - given that the script is running on other hosts just fine. Please read the script with a grain of salt, this is my first run at this, and I am well aware that I am not yet following the conventions of Python. I have much to learn. Thanks, James -- http://mail.python.org/mailman/listinfo/python-list
Human readable number formatting
When reporting file sizes to the user, it's nice to print '16.1 MB', rather than '16123270 B'. This is the behaviour the command 'df -h' implements. There's no python function that I could find to perform this formatting , so I've taken a stab at it: import math def human_readable(n, suffix='B', places=2): '''Return a human friendly approximation of n, using SI prefixes''' prefixes = ['','k','M','G','T'] base, step, limit = 10, 3, 100 if n == 0: magnitude = 0 #cannot take log(0) else: magnitude = math.log(n, base) order = int(round(magnitude)) // step return '%.1f %s%s' % (float(n)/base**(order*step), \ prefixes[order], suffix) Example usage >>> print [human_readable(x) for x in [0, 1, 23.5, 100, 1000/3, 500, 100, 12.345e9]] ['0.0 B', '1.0 B', '23.5 B', '100.0 B', '0.3 kB', '0.5 kB', '1.0 MB', '12.3 GB'] I'd hoped to generalise this to base 2 (eg human_readable(1024, base=2) == '1 KiB' and enforcing of 3 digits at most (ie human_readable(100) == '0.1 KB' instead of '100 B). However I can't get the right results adapting the above code. Here's where I'd like to ask for your help. Am I chasing the right target, in basing my function on log()? Does this function already exist in some python module? Any hints, or would anyone care to finish it off/enhance it? With thanks Alex -- http://mail.python.org/mailman/listinfo/python-list
CSV like file format featured recently in Daily Python URL?
I'm trying to track down the name of a file format and python module, that was featured in the Daily Python URL some time in the last month or two. The format was ASCII with a multiline header defining types for the comma seperated column data below. It may have had the capability to store multiple tables in one file. There was news on the homepage that an alternate 'no data here' syntax was also supported. An example file had vaguely this structure: columnname as datatype columnname as datatype columnname as datatype columnname as datatype data,data,data,data data,"other data",data,data data,data,"",data Can anyone remember this file format/python module? With thanks Alex -- http://mail.python.org/mailman/listinfo/python-list
Re: CSV like file format featured recently in Daily Python URL?
On Fri, 2005-10-07 at 18:56 +0200, Fredrik Lundh wrote: > Alex Willmer wrote: > > > I'm trying to track down the name of a file format and python module, > > that was featured in the Daily Python URL some time in the last month or > > two. > > http://www.netpromi.com/kirbybase.html ? No I don't think that was it. Although KirbyBase looks like a nice project, particularly the alternative to SQL it uses to specify queries. I remember the webpage presenting the format as fairly established and in active use as an export/import medium, the python module was a binding to an existing library. It's very possible I've combined the memories of KirbyBase (for instance) and HDF. My recollection is to say the least, foggy. Thankyou for replying and thankyou for Daily Python-URL. I'll put this on a backburner for now. I may remember it or come across it again by fortune. Alex -- http://mail.python.org/mailman/listinfo/python-list
Re: CSV like file format featured recently in Daily Python URL?
On Thu, 2005-10-06 at 07:44 -0800, EP wrote: > Was it something like ARFF? http://www.cs.waikato.ac.nz/~ml/weka/arff.html Yes that was it thankyou. Although it would seem there isn't a general python module, rather a Cookbook script to perform conversion to SQL. I must have confused ARFF with HDF. > Google "ARFF Python": http://www.google.com/search?q=arff+python Curiously, when I just performed that search, this thread was on the first page of results as a supplemental result. -- http://mail.python.org/mailman/listinfo/python-list
Coding challenge: Optimise a custom string encoding
A challenge, just for fun. Can you speed up this function?
import string
charset = set(string.ascii_letters + string.digits + '@_-')
byteseq = [chr(i) for i in xrange(256)]
bytemap = {byte: byte if byte in charset else '+' + byte.encode('hex')
for byte in byteseq}
def plus_encode(s):
"""Encode a unicode string with only ascii letters, digits, _, -, @, +
"""
bytemap_ = bytemap
s_utf8 = s.encode('utf-8')
return ''.join([bytemap[byte] for byte in s_utf8])
On my machine (Ubuntu 14.04, CPython 2.7.6, PyPy 2.2.1) this gets
alex@martha:~$ python -m timeit -s 'import plus_encode'
'plus_encode.plus_encode(u"""qwertyuiop1234567890!"£$%^&*()EURO""")'
10 loops, best of 3: 2.96 usec per loop
alex@martha:~$ pypy -m timeit -s 'import plus_encode'
'plus_encode.plus_encode(u"""qwertyuiop1234567890!"£$%^&*()EURO""")'
100 loops, best of 3: 1.24 usec per loop
Back story:
Last week we needed a custom encoding to store unicode usernames in a config
file that only allowed mixed case ascii, digits, underscore, dash, at-sign and
plus sign. We also wanted to keeping the encoded usernames somewhat human
readable.
My design was utf-8 and a variant of %-escaping, using the plus symbol. So
u'alic EURO 123' would be encoded as b'alic+e2+82+ac123'. This evening as a
learning exercise I've tried to make it fast. This is the result.
This challenge is just for fun. The chosen solution ended up being
def name_encode(s):
return %s_%s' % (s.encode('utf-8').encode('hex'),
re.replace('[A-Za-z0-9]', '', s))
Regards, Alex
--
https://mail.python.org/mailman/listinfo/python-list
Re: Coding challenge: Optimise a custom string encoding
On Monday, 18 August 2014 21:16:26 UTC+1, Terry Reedy wrote: > On 8/18/2014 3:16 PM, Alex Willmer wrote: > > A challenge, just for fun. Can you speed up this function? > > You should give a specification here, with examples. You should perhaps Sorry, the (informal) spec was further down. > > a custom encoding to store unicode usernames in a config file that only > > allowed mixed case ascii, digits, underscore, dash, at-sign and plus sign. > > We also wanted to keeping the encoded usernames somewhat human readable. > > My design was utf-8 and a variant of %-escaping, using the plus symbol. So > > u'alic EURO 123' would be encoded as b'alic+e2+82+ac123'. Other examples: >>> plus_encode(u'alice') 'alice' >>> plus_encode(u'Bacon & eggs only $19.95') 'Bacon+20+26+20eggs+20only+20+2419+2e95' >>> plus_encode(u'üｎïｃｏԁë') '+c3+bc+ef+bd+8e+c3+af+ef+bd+83+ef+bd+8f+d4+81+c3+ab' > You should perhaps be using .maketrans and .translate. That wouldn't work, maketrans() can only map single bytes to other single bytes. To encode 256 possible source bytes with 66 possible symbols requires a multi-symbol expansion of some or all source bytes. -- https://mail.python.org/mailman/listinfo/python-list
Finding x is 1, and x is 'foo' comparisons in a code base
Hello, I'm looking for a way to find the occurrences of x is y comparisons in an existing code base. Except for a few special cases (e.g. x is [not] None) they're a usually mistakes, the correct test being x == y. However they happen to work most of the time on CPython (e.g. when y is a small integer or string) so they slip into production code unnoticed. PyLint and PyFlakes don't check this AFAICT. Any suggestions for such a tool, or a pointer how to add the check to an existing tool would be most welcome. Regards, Alex -- http://mail.python.org/mailman/listinfo/python-list
Re: Understanding the CPython dict implementation
On Mar 15, 4:06 am, John Nagle wrote: > Is this available as a paper? > > John Nagle It doesn't wppear to be, slides are here: http://us.pycon.org/2010/conference/schedule/event/12/ Alex -- http://mail.python.org/mailman/listinfo/python-list
EuroPython 2010 - Open for registration and reminder of participation
EuroPython 2010 - 17th to 24th July 2010 EuroPython is a conference for the Python programming language community, including the Django, Zope and Plone communities. It is aimed at everyone in the Python community, of all skill levels, both users and programmers. Last year's conference was the largest open source conference in the UK and one of the largest community organised software conferences in Europe. This year EuroPython will be held from the 17th to 24th July in Birmingham, UK. It will include over 100 talks, tutorials, sprints and social events. Registration Registration is open now at: http://www.europython.eu/registration/ For the best registration rates, book as soon as you can! Extra Early Bird closes soon, after which normal Early Bird rate will apply until 10th May Talks, Activities and Events Do you have something you wish to present at EuroPython? You want to give a talk, run a tutorial or sprint? Go to http://www.europython.eu/talks/cfp/ for information and advice! Go to http://wiki.europython.eu/Sprints to plan a sprint! Help Us Out --- EuroPython is run by volunteers, like you! We could use a hand, and any contribution is welcome. Go to http://wiki.europython.eu/Helping to join us! Go to http://www.europython.eu/contact/ to contact us directly! Sponsors Sponsoring EuroPython is a unique opportunity to affiliate with this prestigious conference and to reach a large number of Python users from computing professionals to academics, from entrepreneurs to motivated and well-educated job seekers. http://www.europython.eu/sponsors/ Spread the Word --- We are a community-run not-for-profit conference. Please help to spread the word by distributing this announcement to colleagues, project mailing lists, friends, your blog, Web site, and through your social networking connections. Take a look at our publicity resources: http://wiki.europython.eu/Publicity General Information --- For more information about the conference, please visit the official site: http://www.europython.eu/ Looking forward to see you! The EuroPython Team -- http://mail.python.org/mailman/listinfo/python-list
Re: Splitting a string
On Apr 2, 11:12 am, Thomas Heller wrote:
> Maybe I'm just lazy, but what is the fastest way to convert a string
> into a tuple containing character sequences and integer numbers, like this:
>
> 'si_pos_99_rep_1_0.ita' -> ('si_pos_', 99, '_rep_', 1, '_', 0, '.ita')
>
This is very probably not the fastest execution wise, it was the
fastest development time wise:
import re
def maybe_int(x):
try:
return int(x)
except ValueError:
return x
def strings_n_ints(s):
return tuple(maybe_int(x) for x in re.findall('(\d+|\D+)', s))
>>> strings_n_ints('si_pos_99_rep_1_0.ita')
('si_pos_', 99, '_rep_', 1, '_', 0, '.ita')
Alex
--
http://mail.python.org/mailman/listinfo/python-list
Re: Python creates "locked" temp dir
On Dec 7, 9:03 pm, utabintarbo wrote: > I am using tempfile.mkdtemp() to create a working directory on a > remote *nix system through a Samba share. When I use this on a Windows > box, it works, and I have full access to the created dir. When used on > a Linux box (through the same Samba share), the created directory > shows as "locked", and I am unable to access. Obviously, I need > access. Any clues? You haven't provided enough details to go on. 1. Please post the actual code, and the trace back (if any). 2. When you say "I am unable to access". Do you mean another script/ process is unable to access? If so, that is the point of mkdtemp() - to make a temporary directory that _only_ the creating process can access. If you want to share it then tempfile is not the right module for you. Regards, Alex -- http://mail.python.org/mailman/listinfo/python-list
Re: Python creates "locked" temp dir
On Dec 8, 6:26 pm, Christian Heimes wrote: > There isn't a way to limit access to a single process. mkdtemp creates > the directory with mode 0700 and thus limits it to the (effective) user > of the current process. Any process of the same user is able to access > the directory. > > Christian Quite right. My apologies for confusing temporary file creation, for which exclusive access is used and temporary directory creation for which there is no such mode. -- http://mail.python.org/mailman/listinfo/python-list
Re: string u'hyv\xe4' to file as 'hyvä'
On Dec 27, 6:47 am, "Mark Tolonen" wrote:
> "gintare" wrote in message
> > In file i find 'hyv\xe4' instead of hyv .
>
> When you open a file with codecs.open(), it expects Unicode strings to be
> written to the file. Don't encode them again. Also, .writelines() expects
> a list of strings. Use .write():
>
> import codecs
> item=u'hyv\xe4'
> F=codecs.open('/opt/finnish.txt', 'w+', 'utf8')
> F.write(item)
> F.close()
Gintare, Mark's code is correct. When you are reading the file back
make sure you understand what you are seeing:
>>> F2 = codecs.open('finnish.txt', 'r', 'utf8')
>>> item2 = F2.read()
>>> item2
u'hyv\xe4'
That might like as though item2 is 7 characters long, and it contains
a backslash followed by x, e, 4. However item2 is identical to item,
they both contain 4 characters - the final one being a-umlaut. Python
has shown the string using a backslash escape, because printing a non-
ascii character might fail. You can see this directly, if your Python
session is running in a terminal (or GUI) that can handle non-ascii
characters:
>>> print item2
hyvä
--
http://mail.python.org/mailman/listinfo/python-list
Re: list 2 dict?
On Sunday, January 2, 2011 3:36:35 PM UTC, T wrote: > The grouper-way looks nice, but I tried it and it didn't work: > > from itertools import * > ... > d = dict(grouper(2, l)) > > NameError: name 'grouper' is not defined > > I use Python 2.7. Should it work with this version? No. As Ian said grouper() is a receipe in the itertools documentation. http://docs.python.org/library/itertools.html#recipes The module doesn't provide it directly -- http://mail.python.org/mailman/listinfo/python-list
Re: String building using join
On Sunday, January 2, 2011 5:43:38 PM UTC, gervaz wrote: > Sorry, but it does not work > > >>> def prg3(l): > ... return "\n".join([x for x in l if x]) > ... > >>> prg3(t) > Traceback (most recent call last): > File "", line 1, in > File "", line 2, in prg3 > TypeError: sequence item 0: expected str instance, Test found def prg3(l): return '\n'.join([str(x) for x in l if x]) That should do it -- http://mail.python.org/mailman/listinfo/python-list
Re: Where is win32service
On Sunday, January 2, 2011 6:40:45 PM UTC, catalinf...@gmail.com wrote: > I install Python 2.7 on Windows XP. > I try use : > > import win32service > import win32serviceutil > > But I got that error : > > ImportError: No module named win32service > Where is this module ? It's part of the pywin32 (aka win32all) package http://sourceforge.net/projects/pywin32/ The latest download for your Python version is http://sourceforge.net/projects/pywin32/files/pywin32/Build%20214/pywin32-214.win32-py2.7.exe/download Regards, Alex -- http://mail.python.org/mailman/listinfo/python-list
Python comparison matrix
I've created a spreadsheet that compares the built ins, features and modules of the CPython releases so far. For instance it shows: - basestring was first introduced at version 2.3 then removed in version 3.0 - List comprehensions (PEP 202) were introduced at version 2.0. - apply() was a built in throughout the 1.x and 2.x series, but was deprecated in from 2.3 and removed in 3.0 - Generator functions were first introduced in 2.2 with __future__ import, from 2.3 they were fully supported https://spreadsheets.google.com/pub?key=0At5kubLl6ri7dHU2OEJFWkJ1SE16NUNvaGg2UFBxMUE The current version covers CPython 1.5 - 3.2 on these aspects: - Built in types and functions - Keywords - Modules - Interpreter switches and environment variables - Platforms, including shipped Python version(s) for major Linux distributions - Features/PEPs (incomplete) I gathered the data from the documentation at python.org. It's work in progress so there are plenty of rough edges and holes, but I'd like to get your opinions, feedback and suggestions. - Would you find such a document useful? - What format(s) would be most useful to you (e.g. spreadsheet, pdf, web page(s), database, wall chart, desktop background)? - Are there other aspects/pages that you'd like to see included? - Do you know of source(s) for which versions of CPython supported which operating systems (e.g. the first and last Python release that works on Windows 98 or Mac OS 9)? The best I've found so far is PEP 11 Regards and thanks, Alex -- http://mail.python.org/mailman/listinfo/python-list
Re: Python comparison matrix
On Tuesday, January 4, 2011 12:54:24 AM UTC, Malcolm wrote: > Alex, > > I think this type of documentation is incredibly useful! Thank you. > Is there some type of key which explains symbols like !, *, f, etc? There is a key, it's the second tab from the end, '!' wasn't documented and I forgot why I marked bytes() thusly, so I've removed it. -- http://mail.python.org/mailman/listinfo/python-list
Re: Python comparison matrix
Thank you Antoine, I've fixed those errors. Going by the docs, I have VMSError down as first introduced in Python 2.5. -- http://mail.python.org/mailman/listinfo/python-list
Re: Trying to decide between PHP and Python
On Jan 4, 8:20 pm, Google Poster wrote:
> Can any of you nice folks post a snippet of how to perform a listing
> of the current directory and save it in a string?
>
> Something like this:
>
> $ setenv FILES = `ls`
>
> Bonus: Let's say that I want to convert the names of the files to
> lowercase? As 'tolower()'
I'd just like to mention one more python nicety: list comprehension.
If you wanted the filenames as a list of strings, with each made
lowercase then the following would serve well:
import os
filenames = os.listdir('.')
filenames_lower = [fn.lower() for fn in filenames]
You could also combine this into one line:
import os
filenames_lower = [fn.lower() for fn in os.listdir('.')]
Regards, Alex
--
http://mail.python.org/mailman/listinfo/python-list
Re: Convert unicode escape sequences to unicode in a file
On Jan 11, 8:53 pm, Jeremy wrote:
> I have a file that has unicode escape sequences, i.e.,
>
> J\u00e9r\u00f4me
>
> and I want to replace all of them in a file and write the results to a new
> file. The simple script I've created is copied below. However, I am getting
> the following error:
>
> UnicodeEncodeError: 'ascii' codec can't encode character u'\xe9' in position
> 947: ordinal not in range(128)
>
> It appears that the data isn't being converted when writing to the file. Can
> someone please help?
Are you _sure_ that your file contains the characters '\', 'u', '0',
'0', 'e' and '9'? I expect that actually your file contains a byte
with value 0xe9 and you have inspected the file using Python, which
has printed the byte using a Unicode escape sequence. Open the file
using a text editor or hex editor and look at the value at offset 947
to be sure.
If so, you need to replace 'unicode-escape' with the actual encoding
of the file.
> if __name__ == "__main__":
> f = codecs.open(filename, 'r', 'unicode-escape')
> lines = f.readlines()
> line = ''.join(lines)
> f.close()
>
> utFound = re.sub('STRINGDECODE\((.+?)\)', r'\1', line)
> print(utFound[:1000])
>
> o = open('newDice.sql', 'w')
> o.write(utFound.decode('utf-8'))
> o.close()
--
http://mail.python.org/mailman/listinfo/python-list
Re: How to dump a Python 2.6 dictionary with UTF-8 strings?
On Jan 11, 10:40 pm, "W. Martin Borgert" wrote:
> Hi,
>
> naively, I thought the following code:
>
> #!/usr/bin/env python2.6
> # -*- coding: utf-8 -*-
> import codecs
> d = { u'key': u'我爱中国人' }
> if __name__ == "__main__":
> with codecs.open("ilike.txt", "w", "utf-8") as f:
> print >>f, d
>
> would produce a file ilike.txt like this:
>
> {u'key': u'我爱中国人'}
>
> But unfortunately, it results in:
>
> {u'key': u'\u6211\u7231\u4e2d\u56fd\u4eba'}
>
> What's the right way to get the strings in UTF-8?
>
> Thanks in advance!
It has worked, you're just seeing how python presents unicode
characters in the interactive interpreter:
Python 2.7.1+ (r271:86832, Dec 24 2010, 10:04:43)
[GCC 4.5.2] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> x = {u'key': u'\u6211\u7231\u4e2d\u56fd\u4eba'}
>>> x
{u'key': u'\u6211\u7231\u4e2d\u56fd\u4eba'}
>>> print x
{u'key': u'\u6211\u7231\u4e2d\u56fd\u4eba'}
>>> print x['key']
我爱中国人
That last line only works if your terminal uses an suitable encoding
(e.g. utf-8).
Regards, Alex
--
http://mail.python.org/mailman/listinfo/python-list
Re: Namespaces
On Jan 21, 10:39 am, sl33k_ wrote: > What is namespace? And what is built-in namespace? A namespace is a container for names, like a directory is a container for files. Names are the labels we use to refer to python objects (e.g. int, bool, sys), and each Python object - particularly modules and classes - provides separate namespace. The idea of a namespace is to isolate names from one another - so that if you import module_a and module_b and both have an object called foo then module_a.foo doesn't interfere with module_b.foo. The built-in namespace is where the core objects of Python are named. When you refer to an object such as int Python first searches the local scope (was it defined in the current function/method, i.e. the output of locals()), then module scope (was it defined in the current .py file, i.e. output of globals()) and finally in the object __builtins__. Hope that makes sense. I realised as I typed this my understanding of Python namespaces is not as 100% tight as I thought. Alex -- http://mail.python.org/mailman/listinfo/python-list
Re: interleave string
On Feb 15, 10:09 am, Wojciech Muła
wrote:
> import re
>
> s = 'xxaabbddee'
> m = re.compile("(..)")
> s1 = m.sub("\\1:", s)[:-1]
One can modify this slightly:
s = 'xxaabbddee'
m = re.compile('..')
s1 = ':'.join(m.findall(s))
Depending on one's taste this could be clearer. The more general
answer, from the itertools docs:
from itertools import izip_longest
def grouper(n, iterable, fillvalue=None):
"grouper(3, 'ABCDEFG', 'x') --> ABC DEF Gxx"
args = [iter(iterable)] * n
return izip_longest(fillvalue=fillvalue, *args)
s2 = ':'.join(''.join(pair) for pair in grouper(2, s, ''))
Note that this behaves differently to the previous solutions, for
sequences with an odd length.
--
http://mail.python.org/mailman/listinfo/python-list
Reminder: 6 days left for EuroPython 2010 talk submissions
The EuroPython 2010 call for papers closes this Friday on 30th April. We've already had many submissions covering Python 3, Python 2.7, IronPython, Game Programming, Testing, Behavior Driven Development, NoSQL, Accessiblilty and others. We still are looking for talks and tutorials on Django, PyPy, Twisted, HTML5, Unladen Swallow, Testing and whatever you wish to present. http://www.europython.eu/submission/ EuroPython -- This year EuroPython will be held from the 17th to 24th July in Birmingham, UK. It will include over 100 talks, tutorials, sprints and social events. Confirmed speakers so far include Guido van Rossum, Raymond Hettinger and Brett Cannon. http://www.europython.eu Registration Registration is open now. For the best registration rates, book early! Early Bird rate is open until 10th May. Speakers can attend at the discounted rate Speaker Rate. http://www.europython.eu/registration/ Help Us Out --- EuroPython is run by volunteers, like you! We could use a hand, and any contribution is welcome. Go to http://wiki.europython.eu/Helping to join us! Go to http://www.europython.eu/contact/ to contact us directly! Sponsors Sponsoring EuroPython is a unique opportunity to affiliate with this prestigious conference and to reach a large number of Python users from computing professionals to academics, from entrepreneurs to motivated and well-educated job seekers. http://www.europython.eu/sponsors/ Spread the Word --- We are a community-run not-for-profit conference. Please help to spread the word by distributing this announcement to colleagues, project mailing lists, friends, your blog, Web site, and through your social networking connections. Take a look at our publicity resources: http://wiki.europython.eu/Publicity General Information --- For more information about the conference, please visit the official site: http://www.europython.eu/ Looking forward to see you! The EuroPython Team -- http://mail.python.org/mailman/listinfo/python-list
Re: Get name of file from directory into variable
On Aug 3, 11:21 am, loial wrote:
> In a unix shell script I can do something like this to look in a
> directory and get the name of a file or files into a variable :
>
> MYFILE=`ls /home/mydir/JOHN*.xml`
>
> Can I do this in one line in python?
Depends if you count imports.
import glob
my_files = glob.glob('/home/mydir/JOHN*.xml')
Regards, Alex
--
http://mail.python.org/mailman/listinfo/python-list
Re: The Application cannot locate win32ui.pyd (or Python) (126)
On Aug 4, 2:35 pm, vsoler wrote: > Hi all, > > I just installed python 3.1.2 where I used to have python 2.6.4. I'm > working on Win7. > > The IDLE GUI works, but I get the following message when trying to > open *.py files written for py 2.6 > > The Application cannot locate win32ui.pyd (or Python) (126) > win32ui is part of the PyWin32 package. Most likely you have a version of PyWin32 for Python 2.6 installed, you should uninstall that and install PyWin32 for Python 3.1. Downloads are at http://sourceforge.net/projects/pywin32/files/ You should do the same for any other third party packages that are installed. > Moreover, when I try to open an old *.py file, I sometimes get a > message saying that the file should be converted to UTF-8. What does > this mean? Those files contain non-ascii characters (e.g. £, €, æ). Non-ascii characters must be encoded when saved using and encoding. UTF-8 is one such encoding, and it was chosen as the default .py encoding for Python 3.x. Those files are probably in iso8859, cp432, or perhaps UTF-16 (aka UCS-2). You can save them in UTF-8 using your favourite text editor, or declare the encoding so Python 3 knows it. More info: http://www.joelonsoftware.com/articles/Unicode.html http://docs.python.org/howto/unicode > I'm also trying to use the 2to3 converter, but I cannot see where the > converted files are written to! I think 2to3 prints a diff of the file changes to the console. The -w command line option should modify files in place. -- http://mail.python.org/mailman/listinfo/python-list
Re: The Application cannot locate win32ui.pyd (or Python) (126)
On Aug 4, 5:19 pm, vsoler wrote: > On Aug 4, 5:41 pm, Alex Willmer wrote: > > > > > > > On Aug 4, 2:35 pm, vsoler wrote: > > > > Hi all, > > > > I just installed python 3.1.2 where I used to have python 2.6.4. I'm > > > working on Win7. > > > > The IDLE GUI works, but I get the following message when trying to > > > open *.py files written for py 2.6 > > > > The Application cannot locate win32ui.pyd (or Python) (126) > > > win32ui is part of the PyWin32 package. Most likely you have a version > > of PyWin32 for Python 2.6 installed, you should uninstall that and > > install PyWin32 for Python 3.1. Downloads are > > athttp://sourceforge.net/projects/pywin32/files/ > > > You should do the same for any other third party packages that are > > installed. > > > > Moreover, when I try to open an old *.py file, I sometimes get a > > > message saying that the file should be converted to UTF-8. What does > > > this mean? > > > Those files contain non-ascii characters (e.g. £, €, æ). Non-ascii > > characters must be encoded when saved using and encoding. UTF-8 is one > > such encoding, and it was chosen as the default .py encoding for > > Python 3.x. Those files are probably in iso8859, cp432, or perhaps > > UTF-16 (aka UCS-2). You can save them in UTF-8 using your favourite > > text editor, or declare the encoding so Python 3 knows it. More info: > > >http://www.joelonsoftware.com/articles/Unicode.htmlhttp://docs.python... > > > > I'm also trying to use the 2to3 converter, but I cannot see where the > > > converted files are written to! > > > I think 2to3 prints a diff of the file changes to the console. The -w > > command line option should modify files in place. > > Thank you Alex for your detailes reply. > > Before switching to Python 3.1.2 I removed all my Python 2.6 packages > (python, pywin32, numpy, wxpython). However, the removal was not > complete since some files could not be removed. Additionally, I still > see my C:\python26 directory which is suposed not to exist any longer. It probably contains one or two files the installers weren't aware of. E.g. a module you added manually, a log, a .pyc > I would not like to take a lot of your time, but, do you have any > hints as to what I should do to 'tune' my PC? Take a backup then either delete the Python26 directory, or rename it. Any problems, reverse the process. -- http://mail.python.org/mailman/listinfo/python-list
Re: How to match patterns like XX YY XX YY? (regex)
On Aug 7, 4:48 pm, Peng Yu wrote:
> The problem is that I don't know how to capture pattern that repeat
> itself (like 'a' and 'xy' in the example). I could use 'test\((\w+)
> (\w+)\)(\w) (\w)', but it will capture something like 'test(a b)x y',
> which I don't want to.
>
> I'm wondering if there is way to capture recurring patterns.
Back references can deal with repetition.
Python 2.6.5 (r265:79063, Apr 16 2010, 13:09:56)
[GCC 4.4.3] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> import re
>>> re.match(r'test\((\w+) (\w+)\)\1 \2', 'test(xy uv)xy uv').groups()
('xy', 'uv')
>>> re.match(r'test\((\w+) (\w+)\)\1 \2', 'test(a b)x y')
>>>
--
http://mail.python.org/mailman/listinfo/python-list
Re: Sequential Object Store
On Aug 7, 5:26 pm, GZ wrote:
> I am wondering if there is a module that can persist a stream of
> objects without having to load everything into memory. (For this
> reason, I think Pickle is out, too, because it needs everything to be
> in memory.)
>From the pickle docs it looks like you could do something like:
try:
import cPickle as pickle
except ImportError
import pickle
file_obj = open('whatever', 'wb')
p = pickle.Pickler(file_obj)
for x in stream_of_objects:
p.dump(x)
p.memo.clear()
del p
file_obj.close()
then later
file_obj = open('whatever', 'rb')
p = pickle.Unpickler(file_obj)
while True:
try:
x = p.load()
do_something_with(x)
except EOFError:
break
Your loading loop could be wrapped in a generator function, so only
one object should be held in memory at once.
--
http://mail.python.org/mailman/listinfo/python-list
Re: Python 2.7 re.IGNORECASE broken in re.sub?
On Aug 16, 1:07 am, Steven D'Aprano wrote: > You're passing re.IGNORECASE (which happens to equal 2) as a count > argument, not as a flag. Try this instead: > > >>> re.sub(r"python\d\d" + '(?i)', "Python27", t) > 'Python27' Basically right, but in-line flags must be placed at the start of a pattern, or the result is undefined. Also in Python 2.7 re.sub() has a flags argument. Python 2.7.0+ (release27-maint:83286, Aug 16 2010, 01:25:58) [GCC 4.4.3] on linux2 Type "help", "copyright", "credits" or "license" for more information. >>> import re >>> t = 'Python26' >>> re.sub(r'(?i)python\d\d', 'Python27', t) 'Python27' >>> re.sub(r'python\d\d', 'Python27', t, flags=re.IGNORECASE) 'Python27' Alex -- http://mail.python.org/mailman/listinfo/python-list
Re: Python 2.7 re.IGNORECASE broken in re.sub?
On Aug 16, 12:23 pm, Steven D'Aprano wrote: > On Sun, 15 Aug 2010 17:36:07 -0700, Alex Willmer wrote: > > On Aug 16, 1:07 am, Steven D'Aprano > cybersource.com.au> wrote: > >> You're passing re.IGNORECASE (which happens to equal 2) as a count > >> argument, not as a flag. Try this instead: > > >> >>> re.sub(r"python\d\d" + '(?i)', "Python27", t) > >> 'Python27' > > > Basically right, but in-line flags must be placed at the start of a > > pattern, or the result is undefined. > > Pardon me, but that's clearly not correct, as proven by the fact that the > above example works. Undefined includes 'might work sometimes'. I refer you to the Python documentation: "Note that the (?x) flag changes how the expression is parsed. It should be used first in the expression string, or after one or more whitespace characters. If there are non-whitespace characters before the flag, the results are undefined." http://docs.python.org/library/re.html#regular-expression-syntax -- http://mail.python.org/mailman/listinfo/python-list
Re: Python 2.7 re.IGNORECASE broken in re.sub?
On Aug 16, 1:46 pm, Alex Willmer wrote: > "Note that the (?x) flag changes how the expression is parsed. It > should be used first in the expression string, or after one or more > whitespace characters. If there are non-whitespace characters before > the flag, the results are undefined. > "http://docs.python.org/library/re.html#regular-expression-syntax Hmm, I found a lot of instances that place (?iLmsux) after non- whitespace characters http://google.com/codesearch?hl=en&lr=&q=file:\.py[w]%3F$+[^[:space:]%22']%2B\(\%3F[iLmsux]%2B\) including two from the Python unit tests, re_test.py lines 109-110. Perhaps the documentation is overly cautious.. -- http://mail.python.org/mailman/listinfo/python-list
Re: seach for pattern based on string
On Aug 24, 5:33 pm, richie05 bal wrote:
> i am starting to learn python and I am stuck with query I want to
> generate with python
> File looks something like this
> TRACE: AddNewBookD {bookId 20, noofBooks 6576, authorId 41,
> publishingCompanyId 7}
> TRACE: AddNewBookD {bookId 21, noofBooks 6577, authorId 42,
> publishingCompanyId 8}
>
> I want to first search for AddNewBookD
> if found
> store bookId, noofBooks, authorId and publishingCompanyId
>
> I know how to search for only AddNewBookD or find the pattern bookId
> 20, noofBooks 6576, authorId 41, publishingCompanyId 7 but I don't
> know how search one based on another.
Using a regular expression I would perform a match against each line.
If the match fails, it will return None. If the match succeeds it
returns a match object with which you can extract the values
>>> import re
>>> pattern = re.compile(r'TRACE: AddNewBookD \{bookId (\d+), noofBooks (\d+),
>>> authorId (\d+), publishingCompanyId (\d+)\}\s*')
>>> s = '''TRACE: AddNewBookD {bookId 20, noofBooks 6576, authorId 41,
>>> publishingCompanyId 7} '''
>>> pattern.match(s)
<_sre.SRE_Match object at 0xa362f40> # If the match failed this would
be None
>>> m = pattern.match(s)
>>> m.groups()
('20', '6576', '41', '7')
>>>
So your code to store the result would be inside an if m: block
HTH, Alex
--
http://mail.python.org/mailman/listinfo/python-list
Re: problem with strptime and time zone
On Aug 24, 9:45 pm, m_ahlenius wrote: > > whereas this fails: > myStrA = 'Sun Aug 22 19:03:06 PDT' > gTimeA = strptime( myStrA, '%a %b %d %H:%M:%S %Z') > print "gTimeA = ",gTimeA > > ValueError: time data 'Sun Aug 22 19:03:06 PDT' does not match format > '%a %b %d %H:%M:%S %Z' Support for the %Z directive is based on the values contained in tzname and whether daylight is true. Because of this, it is platform- specific except for recognizing UTC and GMT which are always known (and are considered to be non-daylight savings timezones). http://docs.python.org/library/time.html Dateutil has it's own timezone database, so should work reliably http://labix.org/python-dateutil -- http://mail.python.org/mailman/listinfo/python-list
Re: problem with strptime and time zone
On Aug 25, 8:48 am, Lawrence D'Oliveiro wrote: > In message > <45faa241-620e-42c7-b524-949936f63...@f6g2000yqa.googlegroups.com>, Alex > > Willmer wrote: > > Dateutil has it's own timezone database ... > > I hate code which doesn’t just use /usr/share/zoneinfo. How many places do > you need to patch every time somebody changes their daylight-saving rules? >From reading http://labix.org/python-dateutil can read timezone information from several platforms, including /usr/share/zoneinfo. I don't know whether one chooses the source explicitly, or if it is detected with fall back to the internal database. -- http://mail.python.org/mailman/listinfo/python-list
Re: New implementation of re module
On Jul 27, 5:34 pm, MRAB wrote:
> Hi all,
>
> I've been working on a new implementation of the re module. The details
> are athttp://bugs.python.org/issue2636, specifically
> fromhttp://bugs.python.org/issue2636#msg90954. I've included a .pyd file for
> Python 2.6 on Windows if you want to try it out.
Firstly Matthew, thank you for all your work on this. It brings some
very nice regex features to Python.
I've used Christopher Arndt's post as a basis and created a package
from you latest upload (issue2636-20090804.zip), which builds for
Python 2.5 and 2.6. I'd like to see this on PyPI, so it's easier to
install the module and your work gets wider exposure. Would this be
alright and would you prefer to have control of the upload, as this is
your work?
Below is the setup.py, the unicodedata_db.h files are taken from the
appropriate branches on svn.python.org
#!/usr/bin/env python
import shutil
import sys
from distutils.core import setup, Extension
MAJOR, MINOR = sys.version_info[:2]
# Copy appropriate unicodedata_db.h, not found in published includes
if (MAJOR, MINOR) == (2, 6):
shutil.copy('Python26/unicodedata_db.h', './')
elif (MAJOR, MINOR) == (2, 5):
shutil.copy('Python25/unicodedata_db.h', './')
else:
print "WARNING: No unicodedata_db.h prepared."
setup(
name='regex',
version='20080804',
description='Alternate regular expression module, to replace re.',
author='Matthew Barnett',
author_email='pyt...@mrabarnett.nospam.plus.com', # Obsfucated
url='http://bugs.python.org/issue2636',
py_modules = ['regex'],
ext_modules=[Extension('_regex', ['_regex.c'])],
)
Sincerely, Alex Willmer
--
http://mail.python.org/mailman/listinfo/python-list
Re: Where do I report a bug to the pythonware PIL
On Sep 3, 10:35 am, "jc.lopes" wrote: > Does anyone knows what is the proper way to submit a bug report to > pythonware PIL? > > thanks > JC Lopes The Python Image SIG list http://mail.python.org/mailman/listinfo/image-sig "Free Support: If you don't have a support contract, please send your question to the Python Image SIG mailing list. The same applies for bug reports and patches." -- http://www.pythonware.com/products/pil/ They don't appear to have a dedicated mailing list or public bug tracker. -- http://mail.python.org/mailman/listinfo/python-list
Re: Plz comment on this code
Your code works (assuming digits gets populated fully), but it's the
absolute bare minimum that would.
To be brutally honest it's:
- unpythonic - you've not used the core features of Python at all,
such as for loops over a sequence
- poorly formatted - Please read the python style guide and follow it
- not reusable - Your code can only be called from the command line,
it should be usable as a module
- not documented - There is no indication what this code does, other
than mentally running it
- Fragile - There is no error checking on user input
There are other ways to write what you have more concisely (e.g. list
comprehensions, iterators) but those can wait for another time. Here
is a start at improving your code wrt to the above points:
#!/usr/bin/env python3
# bigdigits2.py
ZERO = ["***", # NB Constants are by convention ALL_CAPS
"* *",
"***"]
ONE = ["** ",
" * ",
"***"]
# TODO Define and populate digits 2-9
DIGITS = [ZERO, ONE, ZERO, ONE, ZERO, ONE, ZERO, ONE, ZERO, ONE]
def big_digits(str_of_digits):
"""Return a list of lines representing the digits using 3x3 blocks
of "*"
"""
banner = [] # Accumulate results in this
# Loop over the rows/lines of the result
# TODO Replace hard coded block size with global constant or
measured size
for row in range(3):
line_parts = []
# Assemble the current line from the current row of each big
digit
for digit in str_of_digits:
big_digit = DIGITS[int(digit)]
line_parts.append(big_digit[row])
# Create a string for the current row and add it to the result
line = " ".join(line_parts)
banner.append(line)
return banner
def usage():
print("Usage: bigdigit.py ", file=sys.stderr)
sys.exit(1)
if __name__ == "__main__":
import sys
# Check that an argument was passed
# NB This will ignore additional arguments
if len(sys.argv) >= 2:
input_string = sys.argv[1]
else:
usage()
# Check that only digits were passed
if not input_string.isnumeric():
usage()
# All is well, print the output
for line in big_digits(input_string):
print(line)
Here are some suggested further improvements:
- Map directly from a digit to it's big digit with a dictionary,
rather than indexing into a list:
BIG_DIGITS = {
"1": ["** ",
" * ",
"***"],
# ...
}
- Is input_string.isnumeric() the right test? Can you find a character
it would not correctly flag as invalid input?
- What if I wanted to use my own 4x4 big digits? Could the
big_digits() function accept it as an argument?
--
http://mail.python.org/mailman/listinfo/python-list
Re: Plz comment on this code
On Sep 19, 12:20 pm, Lawrence D'Oliveiro wrote: > In message > , Alex > > Willmer wrote: > > # NB Constants are by convention ALL_CAPS > > SAYS_WHO? Says PEP 8: Constants Constants are usually declared on a module level and written in all capital letters with underscores separating words. Examples include MAX_OVERFLOW and TOTAL. -- http://www.python.org/dev/peps/pep-0008/ -- http://mail.python.org/mailman/listinfo/python-list
Re: if the else short form
On Sep 29, 12:38 pm, Hrvoje Niksic wrote:
> Tracubik writes:
> > Hi all,
> > I'm studying PyGTK tutorial and i've found this strange form:
>
> > button = gtk.Button(("False,", "True,")[fill==True])
>
> > the label of button is True if fill==True, is False otherwise.
>
> The tutorial likely predates if/else expression syntax introduced in
> 2.5, which would be spelled as:
>
> button = gtk.Button("True" if fill else "False")
>
> BTW adding "==True" to a boolean value is redundant and can even break
> for logically true values that don't compare equal to True (such as the
> number 10 or the string "foo").
Totally agreed with one nit. If one chooses to fake
x = true_val if expr else false_val
prior to Python 2.5, with
x = (false_val, true_val)[expr]
then one should ensure that expr evaluates to either 0, 1 or a bool.
If expr evaluates to "fred" or 42 a TypeError or IndexError will
occur. So better to use (in original line)
button = gtk.Button(("False,", "True,")[bool(fill)])
but still best for readability, to use a full if-else block
--
http://mail.python.org/mailman/listinfo/python-list
Re: Problem installing psycopg2 in virtualenv (Ubuntu 10.04, Python 2.5)
On Oct 5, 7:41 am, Pascal Polleunus wrote: > On 05/10/10 00:11, Diez B. Roggisch wrote: > > Install the python-dev-package. It contains the Python.h file, which the > > above error message pretty clearly says. Usually, it's a good idea to > > search package descriptions of debian/ubuntu packages for missing header > > files to know what to install. > > It's already installed; at least for 2.6, nor sure it's correct for 2.5. > python2.5-dev is not available but python-old-doctools replaces it. Ubuntu 10.04 doesn't have a full Python 2.5 packaged, as evidenced by the lack of python2.5-dev. You need to use Python 2.6 or if you absolutely must use Python 2.5 build it from source, try a Debian package or switch distro. python-old-doctools does not replace python- dev, it looks like it was bodged to keep some latex tools working. Regards, Alex -- http://mail.python.org/mailman/listinfo/python-list
Re: Why "flat is better than nested"?
On Oct 25, 11:07 am, kj wrote: > In "The Zen of Python", one of the "maxims" is "flat is better than > nested"? Why? Can anyone give me a concrete example that illustrates > this point? I take this as a reference to the layout of the Python standard library and other packages i.e. it's better to have a module hierarchy of depth 1 or 2 and many top level items, than a depth of 5+ and only a few top level items. For instance import re2 import sqlite3 import logging import something_thirdparty vs import java.util.regex import java.sql import java.util.logging import org.example.thirdparty.something There are of course some Python packages that go deeper than 2 (xml.dom.minidom), but the majority are shallow. I think the motivation is to make the packages more discoverable, and to avoid classification arguments (does regex go under util or text). Alone the statement would imply a single, global space ala C but that of course is evil and so one must balance it with "Namespaces are one honking great idea -- let's do more of those!" I don't think it applies to data structures though. If a deeply nested tree models your data well, then use it. Regards, Alex -- http://mail.python.org/mailman/listinfo/python-list
Re: Why "flat is better than nested"?
On Oct 25, 2:56 pm, Robin Becker wrote: > On 25/10/2010 11:07, kj wrote: > > > In "The Zen of Python", one of the "maxims" is "flat is better than > > nested"? Why? Can anyone give me a concrete example that illustrates > > this point? > > ... > I believe that the following illustrates the nesting issue (I think this is > from > somewhere in Chomsky) > > The rat ate the corn. > The rat that the cat killed ate the corn. > The rat that the cat that the dog chased killed ate the corn. > > I believe this is called central embedding. > > There's also the old schoolboy saying "I know that that that that that boy > said > is wrong!". > > The nested nature makes the semantics quite hard. The same will be true of > nested tuple/list and similar programming structures. I agree in the case of a suped-up hierachical record structure that encourages code like my_far = the_record.something.something_else.foo[2].keep_going.bar.baz() A tree of homogeneous nodes that one walks or recurses into (e.g. a b- tree or r-tree) is a case where I would ignore this maxim -- http://mail.python.org/mailman/listinfo/python-list
Re: 'NoneType' object has no attribute 'bind'
On Oct 28, 11:24 am, Alex wrote:
> hi there, I keep getting the message in the Topic field above.
>
> Here's my code:
>
> self.click2=Button(root,text="Click Me").grid(column=4,row=10)
> self.click2.bind("",self.pop2pop)
>From reading the Tkinter docs grid doesn't itself return a control. So
I think you want this:
self.click2 = Button(root, text="Click Me")
self.click2.grid(column=4, row=10)
self.click2.bind("", self.pop2pop)
However, that's totally untested so don't take it as gospel.
> def pop2pop(self,event):
>
> print("Adsfadsf")
> newpop=IntVar()
> newpop=self.PopSize.get();
>
> what am I doing wrong?
>
> cheers,
>
> Alex
--
http://mail.python.org/mailman/listinfo/python-list
Re: Would you recommend python as a first programming language?
On Oct 30, 7:16 pm, brad...@hotmail.com wrote: > I was thinking of recommending this to a friend but what do you all think? > I think 1. Python is a great language, and a good starting point for many people. 2. You really haven't given us much to go on. Regards, Alex -- http://mail.python.org/mailman/listinfo/python-list
