accents in windows

[C@rlos]

i cant print any accent(á é í ó ú) or ñ in console when i use windows OS with 
python, the console showme an error or extrangers characters in some cases, i 
need help 

III Escuela Internacional de Invierno en la UCI del 17 al 28 de febrero del 
2014. Ver www.uci.cu

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testfixtures 4.1.1 Released!

[Chris Withers]

Hi All,

I'm pleased to announce the release of testfixtures 4.1.1. This is a 
bugfix release that fixes the following:


- Fix bug that prevented logger propagation to be controlled by the
  log_capture decorator.

Thanks to John Kristensen for the fix.

It looks like I also forgot to send out the 4.1.0 release announcement, 
which was a bug and feature release containing the following:


- Fix compare() bug when dict instances with tuple keys were not equal.

- Allow logger propagation to be controlled by LogCapture.

- Enabled disabled loggers if a LogCapture is attached to them.

Thanks to Daniel Fortunov for the compare() fix.

The package is on PyPI and a full list of all the links to docs, issue 
trackers and the like can be found here:


http://www.simplistix.co.uk/software/python/testfixtures

Any questions, please do ask on the Testing in Python list or on the 
Simplistix open source mailing list...


cheers,

Chris

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Re: accents in windows

[Chris Angelico]

On Thu, Oct 30, 2014 at 11:03 AM, C@rlos  wrote:
> i cant print any accent(á é í ó ú) or ñ in console  when i use windows OS
> with python, the console showme an error or extrangers characters in some
> cases, i need help

What version of Python? What is your code page set to?

Windows and Unicode don't play very nicely together. You may find it
better to use Idle (which has a GUI for this kind of display), and you
will almost certainly find things easier on Linux.

ChrisA
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Re: Python Style Question

[Steven D'Aprano]

Anton wrote:

> Let's say I have an incoming list of values *l*. Every element of *l* can
> be one of the following options: 
> 1) an integer value 
> 2) a string in form of '', e.g. '7'
> 3) a string with a json serialization of an integer value, e.g. '"7"'
> 4) something else that should be ignored
> 
> I need to transform this list into another list with values from options
> 1)-3) coerced to int. The code below should do this.

I don't particularly like either version. I prefer this:

def load_int(obj):
if isinstance(obj, int):
# Case 1), an int, e.g. 7
return obj
elif isinstance(obj, str):
# Case 2) and 3), a str or JSON serialised int.
# E.g. '7' or '"7"'.
try:
return int(obj)
except ValueError:
return int(json.loads(obj))
raise TypeError('require int or str, got %s' % type(obj).__name__)

load_int() covers the three cases you mention, and raises either ValueError
for malformed strings (e.g. 'x') or TypeError for things which aren't ints
(e.g. floats, dicts, etc.). Any other exception is probably a bug that
needs to be fixed.

Then, to cover case 4), ignoring everything else, you have a choice between
a procedural form:

values = []
for obj in l:
try:
values.append(load_int(obj))
except (ValueError, TypeError):
pass


or a functional form:

def tolerant_load_int(obj, default=None):
try:
return load_int(obj)
except (ValueError, TypeError):
return default

values = [n for n in map(tolerant_load_int, l) if n is not None]

# alternative to using map
values = [n for n in (tolerant_load_int(obj) for obj in l) if n is not None]



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Has color "Green" changed from Python 33 to 34 ?

[ast]

Hi

I just updated this morning my Python from a 3.3rc to 3.4 
(Windows) and I noticed that the 'Green' color in tkinter 
GUI is not the same at all.


'Green' in 3.4 is very dark. I had to replace it with 'Lime' to
get back a nice 'Green'.
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Re: Has color "Green" changed from Python 33 to 34 ?

[Peter Otten]

ast wrote:

> I just updated this morning my Python from a 3.3rc to 3.4
> (Windows) and I noticed that the 'Green' color in tkinter
> GUI is not the same at all.
> 
> 'Green' in 3.4 is very dark. I had to replace it with 'Lime' to
> get back a nice 'Green'.

More likely the color is defined by tcl/tk rather than Python, and your 
Python installations use different versions of tcl. Searching for 'tcl/tk 
color definitions' finds  with the following 
statement

"""From Tcl/Tk 8.6 on, Tk uses Web colours instead of X11 ones, where they 
conflict.
"""

and according to 

 
"green" is indeed one of the affected colors.


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Re: Python Style Question

[MRAB]

On 2014-10-30 11:10, Steven D'Aprano wrote:

Anton wrote:


Let's say I have an incoming list of values *l*. Every element of *l* can
be one of the following options:
1) an integer value
2) a string in form of '', e.g. '7'
3) a string with a json serialization of an integer value, e.g. '"7"'
4) something else that should be ignored

I need to transform this list into another list with values from options
1)-3) coerced to int. The code below should do this.


I don't particularly like either version. I prefer this:

def load_int(obj):
 if isinstance(obj, int):
 # Case 1), an int, e.g. 7
 return obj
 elif isinstance(obj, str):
 # Case 2) and 3), a str or JSON serialised int.
 # E.g. '7' or '"7"'.
 try:
 return int(obj)
 except ValueError:
 return int(json.loads(obj))
 raise TypeError('require int or str, got %s' % type(obj).__name__)


[snip]

How about:

int(str(obj).strip('"'))

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Re: accents in windows

[C@rlos]

thanks U, but the real problem is:

i have a path C:\Users\yanet\Desktop\áaaéeeíiiióooúuuñnn 
this path is correct, áaaéeeíiiióooúuuñnn is the name of a directory
but when i try to use os.walk() usin this path, dont work, for os this path 
dont exist, i try every things but nothing works.

some help???


- Mensaje original -
De: "Chris Angelico" 
CC: python-list@python.org
Enviados: Jueves, 30 de Octubre 2014 4:42:49
Asunto: Re: accents in windows

On Thu, Oct 30, 2014 at 11:03 AM, C@rlos  wrote:
> i cant print any accent(á é í ó ú) or ñ in console  when i use windows OS
> with python, the console showme an error or extrangers characters in some
> cases, i need help

What version of Python? What is your code page set to?

Windows and Unicode don't play very nicely together. You may find it
better to use Idle (which has a GUI for this kind of display), and you
will almost certainly find things easier on Linux.

ChrisA
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-- 
Conserva lo que tienes...Olvida lo que te duele...Lucha por lo que quieres... 
Valora lo que posees...Perdona a los que te hieren y disfruta a los que te 
aman. Nos pasamos la vida esperando que pase algo... y lo único que pasa es la 
vida. No entendemos el valor de los momentos, hasta que se han convertido en 
recuerdos. Por eso... Haz lo que quieras hacer, antes de que se convierta en lo 
que te "gustaría" haber hecho.. No hagas de tu vida un borrador, tal vez no 
tengas tiempo de pasarlo en limpio !! 

.C@rlos 

III Escuela Internacional de Invierno en la UCI del 17 al 28 de febrero del 
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When using a decorator exceptions raised reference the decorator not the function

[Néstor Boscán]

Hi

I'm using Python 2.7 and I'm creating a class decorator that extract
information from exceptions for logging purposes.

Everytime an exception is raised from the original function and I extract
the origin of the exception with sys.exc_info() I get a reference to the
line in the decorator where the function is called, not the line of the
original function where the exception was raised.

Any ideas?

Regards,

Néstor
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Re: accents in windows

[Peter Otten]

C@rlos wrote:

> thanks U, but the real problem is:
> 
> i have a path C:\Users\yanet\Desktop\áaaéeeíiiióooúuuñnn
> this path is correct, áaaéeeíiiióooúuuñnn is the name of a directory
> but when i try to use os.walk() usin this path, dont work, for os this
> path dont exist, i try every things but nothing works.
> 
> some help???

"nothing works" is not a good problem description to get help to fix a bug.

Can you post a small script that demonstrates the problem? 

Run the script and post its output including the error message and the 
traceback. Don't retype the output, use copy-and-paste.

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Re: When using a decorator exceptions raised reference the decorator not the function

[Peter Otten]

Néstor Boscán wrote:

> I'm using Python 2.7 and I'm creating a class decorator that extract
> information from exceptions for logging purposes.
> 
> Everytime an exception is raised from the original function and I extract
> the origin of the exception with sys.exc_info() I get a reference to the
> line in the decorator where the function is called, not the line of the
> original function where the exception was raised.
> 
> Any ideas?

Please show us the code, preferably as a small self-contained example. Thank 
you.

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Re: When using a decorator exceptions raised reference the decorator not the function

[Jean-Michel Pichavant]

- Original Message -
> From: "Peter Otten" <__pete...@web.de>
> To: python-list@python.org
> Sent: Thursday, 30 October, 2014 1:45:42 PM
> Subject: Re: When using a decorator exceptions raised reference the decorator 
> not the function
> 
> Néstor Boscán wrote:
> 
> > I'm using Python 2.7 and I'm creating a class decorator that
> > extract
> > information from exceptions for logging purposes.
> > 
> > Everytime an exception is raised from the original function and I
> > extract
> > the origin of the exception with sys.exc_info() I get a reference
> > to the
> > line in the decorator where the function is called, not the line of
> > the
> > original function where the exception was raised.
> > 
> > Any ideas?
> 
> Please show us the code, preferably as a small self-contained
> example. Thank
> you.

+1 show us your decorator.

if you did something like:

try:

except Exception, e:
  # do something
  raise e


Then replace "raise e" by a bare "raise"


JM


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Finding way around ABCs (was What for -- for? (was A bug?))

[Rustom Mody]

On Wednesday, October 29, 2014 11:49:27 AM UTC+5:30, Zachary Ware wrote:
> On Wed, Oct 29, 2014 at 1:11 AM, Rustom Mody wrote:
> > On Wednesday, October 29, 2014 11:10:06 AM UTC+5:30, Zachary Ware wrote:
> >> Of course, that's 3 (progressively shorter) loops to get the names of
> >> the ABCs of a class compared to 1 (fairly short in the first place)
> >> loop for a map of relationships to all available ABCs, but optimizing
> >> such a toy as this would just be an exercise in futility :)
> >
> > Not so.
> >
> > The charm of introspection is that the introspection
> > itself can be introspected.
> > For that to be convincing there needs to be a good combo
> > of clarity and succinctness.  In particular why not reduce
> > the two functions to one?
> >
> > def get_abc_names(cls):
> > return [abc.__name__ for abc in abcs if issubclass(cls,abc)]
> 
> Well, it depends on what you actually want, the spec has been a bit fuzzy ;)

Thanks for this much -- its helpful.
Regarding ABCs -- is there a central documentation for them:

"What exactly is a sequence or iterable or etc protocol?"

This information seems to be strewn all over the place but systematically.
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Re: Finding way around ABCs (was What for -- for? (was A bug?))

[Ian Kelly]

On Thu, Oct 30, 2014 at 11:01 AM, Rustom Mody  wrote:
> On Wednesday, October 29, 2014 11:49:27 AM UTC+5:30, Zachary Ware wrote:
>> On Wed, Oct 29, 2014 at 1:11 AM, Rustom Mody wrote:
>> > On Wednesday, October 29, 2014 11:10:06 AM UTC+5:30, Zachary Ware wrote:
>> >> Of course, that's 3 (progressively shorter) loops to get the names of
>> >> the ABCs of a class compared to 1 (fairly short in the first place)
>> >> loop for a map of relationships to all available ABCs, but optimizing
>> >> such a toy as this would just be an exercise in futility :)
>> >
>> > Not so.
>> >
>> > The charm of introspection is that the introspection
>> > itself can be introspected.
>> > For that to be convincing there needs to be a good combo
>> > of clarity and succinctness.  In particular why not reduce
>> > the two functions to one?
>> >
>> > def get_abc_names(cls):
>> > return [abc.__name__ for abc in abcs if issubclass(cls,abc)]
>>
>> Well, it depends on what you actually want, the spec has been a bit fuzzy ;)
>
> Thanks for this much -- its helpful.
> Regarding ABCs -- is there a central documentation for them:
>
> "What exactly is a sequence or iterable or etc protocol?"
>
> This information seems to be strewn all over the place but systematically.

Maybe the glossary?

https://docs.python.org/3/glossary.html
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Re: Finding way around ABCs (was What for -- for? (was A bug?))

[Ian Kelly]

On Thu, Oct 30, 2014 at 11:09 AM, Ian Kelly  wrote:
> On Thu, Oct 30, 2014 at 11:01 AM, Rustom Mody  wrote:
>> On Wednesday, October 29, 2014 11:49:27 AM UTC+5:30, Zachary Ware wrote:
>>> On Wed, Oct 29, 2014 at 1:11 AM, Rustom Mody wrote:
>>> > On Wednesday, October 29, 2014 11:10:06 AM UTC+5:30, Zachary Ware wrote:
>>> >> Of course, that's 3 (progressively shorter) loops to get the names of
>>> >> the ABCs of a class compared to 1 (fairly short in the first place)
>>> >> loop for a map of relationships to all available ABCs, but optimizing
>>> >> such a toy as this would just be an exercise in futility :)
>>> >
>>> > Not so.
>>> >
>>> > The charm of introspection is that the introspection
>>> > itself can be introspected.
>>> > For that to be convincing there needs to be a good combo
>>> > of clarity and succinctness.  In particular why not reduce
>>> > the two functions to one?
>>> >
>>> > def get_abc_names(cls):
>>> > return [abc.__name__ for abc in abcs if issubclass(cls,abc)]
>>>
>>> Well, it depends on what you actually want, the spec has been a bit fuzzy ;)
>>
>> Thanks for this much -- its helpful.
>> Regarding ABCs -- is there a central documentation for them:
>>
>> "What exactly is a sequence or iterable or etc protocol?"
>>
>> This information seems to be strewn all over the place but systematically.
>
> Maybe the glossary?

Also the documentation for the collections.abc and numbers modules:

https://docs.python.org/3/library/collections.abc.html
https://docs.python.org/3/library/numbers.html
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Re: Finding way around ABCs (was What for -- for? (was A bug?))

[Rustom Mody]

On Thursday, October 30, 2014 10:40:42 PM UTC+5:30, Ian wrote:
> On Thu, Oct 30, 2014 at 11:01 AM, Rustom Mody wrote:
> > On Wednesday, October 29, 2014 11:49:27 AM UTC+5:30, Zachary Ware wrote:
> >> On Wed, Oct 29, 2014 at 1:11 AM, Rustom Mody wrote:
> >> > On Wednesday, October 29, 2014 11:10:06 AM UTC+5:30, Zachary Ware wrote:
> >> >> Of course, that's 3 (progressively shorter) loops to get the names of
> >> >> the ABCs of a class compared to 1 (fairly short in the first place)
> >> >> loop for a map of relationships to all available ABCs, but optimizing
> >> >> such a toy as this would just be an exercise in futility :)
> >> >
> >> > Not so.
> >> >
> >> > The charm of introspection is that the introspection
> >> > itself can be introspected.
> >> > For that to be convincing there needs to be a good combo
> >> > of clarity and succinctness.  In particular why not reduce
> >> > the two functions to one?
> >> >
> >> > def get_abc_names(cls):
> >> > return [abc.__name__ for abc in abcs if issubclass(cls,abc)]
> >>
> >> Well, it depends on what you actually want, the spec has been a bit fuzzy 
> >> ;)
> >
> > Thanks for this much -- its helpful.
> > Regarding ABCs -- is there a central documentation for them:
> >
> > "What exactly is a sequence or iterable or etc protocol?"
> >
> > This information seems to be strewn all over the place but systematically.
> 
> Maybe the glossary?
> 
> https://docs.python.org/3/glossary.html

Ummm...

I was looking for something more reference-ish, ie
More prolix for ABCs
And not containing random bits of unconnected data like
- What is CPython
- What is EAFP

Maybe there's something in the bowels of the C(Python)-code?
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Re: What for -- for? (was A bug?)

[Joshua Landau]

On 29 October 2014 03:22, Rustom Mody  wrote:
> Yesterday I was trying to introduce python to some senior computer scientists.
>
> Tried showing a comprehension-based dir-walker vs a for-loop based one:
>
> def dw(p):
>if isfile(p):
>   return [p]
>else:
>   return [p] + [c for f in listdir(p) for c in dw(p+'/'+f)]
>
...
>
> Comment to me : "Well this is neat and compact, but it does not add
> anything fundamental (over usual index based for-loops)"
>
> I tried to say that 'for' over general sequences is quite different
> and significantly more powerful than C/Pascal for over indexes +
> explicit indexing.

If you really want to show the generality of iteration, I suggest you
start with iterators:

def walk(path):
yield path

if isdir(path):
for name in iterdir(path):
for file in walk(path + "/" + name):
yield file

This is fundementally inexpressable with indexes. It also lends itself
to expressing delegation (eg. "yield from walk(path + "/" + name)").
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Re: What for -- for? (was A bug?)

[Rustom Mody]

On Thursday, October 30, 2014 10:53:13 PM UTC+5:30, Joshua Landau wrote:
> On 29 October 2014 03:22, Rustom Mody  wrote:
> > Yesterday I was trying to introduce python to some senior computer 
> > scientists.
> >
> > Tried showing a comprehension-based dir-walker vs a for-loop based one:
> >
> > def dw(p):
> >if isfile(p):
> >   return [p]
> >else:
> >   return [p] + [c for f in listdir(p) for c in dw(p+'/'+f)]
> >
> ...
> >
> > Comment to me : "Well this is neat and compact, but it does not add
> > anything fundamental (over usual index based for-loops)"
> >
> > I tried to say that 'for' over general sequences is quite different
> > and significantly more powerful than C/Pascal for over indexes +
> > explicit indexing.
> 
> If you really want to show the generality of iteration, I suggest you
> start with iterators:
> 
> def walk(path):
> yield path
> 
> if isdir(path):
> for name in iterdir(path):
> for file in walk(path + "/" + name):
> yield file

heh!
That was my next version -- almost word-for-word
[Not on that laptop now; will check later]
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Re: Has color "Green" changed from Python 33 to 34 ?

[Terry Reedy]

On 10/30/2014 8:20 AM, Peter Otten wrote:

ast wrote:


I just updated this morning my Python from a 3.3rc to 3.4
(Windows) and I noticed that the 'Green' color in tkinter
GUI is not the same at all.

'Green' in 3.4 is very dark. I had to replace it with 'Lime' to
get back a nice 'Green'.


More likely the color is defined by tcl/tk rather than Python, and your
Python installations use different versions of tcl.

> Searching for 'tcl/tk

color definitions' finds  with the following
statement

"""From Tcl/Tk 8.6 on, Tk uses Web colours instead of X11 ones, where they
conflict.
"""


3.4 switched from 8.5 to 8.6


and according to

"green" is indeed one of the affected colors.


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Re: accents in windows

[Terry Reedy]

On 10/30/2014 8:30 AM, C@rlos wrote:

thanks U, but the real problem is:

i have a path C:\Users\yanet\Desktop\áaaéeeíiiióooúuuñnn
this path is correct, áaaéeeíiiióooúuuñnn is the name of a directory
but when i try to use os.walk() usin this path, dont work, for os this

> path dont exist, i try every things but nothing works.


some help???


Using Python 3.4 should solve this problem.



- Mensaje original -
De: "Chris Angelico" 
CC: python-list@python.org
Enviados: Jueves, 30 de Octubre 2014 4:42:49
Asunto: Re: accents in windows

On Thu, Oct 30, 2014 at 11:03 AM, C@rlos  wrote:

i cant print any accent(á é í ó ú) or ñ in console  when i use windows OS
with python, the console showme an error or extrangers characters in some
cases, i need help


Using Idle and a font with accented chars should solve this problem.


What version of Python? What is your code page set to?

Windows and Unicode don't play very nicely together. You may find it
better to use Idle (which has a GUI for this kind of display), and you
will almost certainly find things easier on Linux.


--
Terry Jan Reedy


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Re: When using a decorator exceptions raised reference the decorator not the function

[Terry Reedy]

On 10/30/2014 8:33 AM, Néstor Boscán wrote:


I'm using Python 2.7 and I'm creating a class decorator that extract
information from exceptions for logging purposes.

Everytime an exception is raised from the original function and I
extract the origin of the exception with sys.exc_info() I get a
reference to the line in the decorator where the function is called, not
the line of the original function where the exception was raised.


I expect that both lines should be in the traceback.  Post an example 
where you do not intercept the exception.


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pySerial works in miniterm but not in my app

[Dario]

Python 2.7.6 on Mint, pySerial 2.6

I'm trying to write a console app to control a certain device via a usb com 
port.

In miniterm (-p /dev/ttyUSB0 -e -b 19200), I can communicate correctly with 
this configuration:

--- Settings: /dev/ttyUSB0  19200,8,N,1
--- RTS: inactive  DTR: inactive  BREAK: inactive
--- CTS: inactive  DSR: inactive  RI: inactive  CD: inactive
--- software flow control: inactive
--- hardware flow control: inactive
--- data escaping: raw  linefeed: CR

sw o01 + <--- I send this
sw o01 + Command OK <--- device does what it should *and* I receive this


Now my code:


import serial

s = serial.serial_for_url(
'/dev/ttyUSB0',
19200,
bytesize = 8,
parity   = 'N',
stopbits = 1,
rtscts   = False,
dsrdtr   = False,
xonxoff  = False,
timeout  = 1 # tried without
)
s.close() # tried without
s.open()
s.write('sw o01 +\r')
s.flush() # tried without
s.close() # tried with a sleep before close


With this I don't receive anything (tried with readline etc, omitted for 
readability), and the device doesn't react. Also, if I connect again with 
miniterm and issue the command, I first receive a "wrong command" message, as 
if some garbage was actually sent by my app, then it works again.

Isn't my config equivalent to the one in miniterm? Anything missing?

Thanks

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Classes

[Seymore4Head]

class pet: 
def set_age(self,age):
self.age=age
def get_age(self):
return self.age
pax=pet
pax.set_age(4)

Traceback (most recent call last):
  File "C:\Functions\test.py", line 18, in 
pax.set_age(4)
TypeError: set_age() missing 1 required positional argument: 'age'

I am trying to pass 4 as the age.  Obviously I am doing it wrong.

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Re: Classes

[Rob Gaddi]

On Thu, 30 Oct 2014 16:16:51 -0400
Seymore4Head  wrote:

> class pet: 
> def set_age(self,age):
> self.age=age
> def get_age(self):
> return self.age
> pax=pet
> pax.set_age(4)
> 
> Traceback (most recent call last):
>   File "C:\Functions\test.py", line 18, in 
> pax.set_age(4)
> TypeError: set_age() missing 1 required positional argument: 'age'
> 
> I am trying to pass 4 as the age.  Obviously I am doing it wrong.
> 

The reason your call is missing the positional argument is that 4 is
being assigned to self, rather than to age, so there is no age.  This is
because you are trying to call a function of the class object, rather
than a function of an instance of the class.

pax=pet()

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Email address domain is currently out of order.  See above to fix.
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Re: Classes

[sohcahtoa82]

On Thursday, October 30, 2014 1:19:57 PM UTC-7, Seymore4Head wrote:
> class pet: 
> def set_age(self,age):
> self.age=age
> def get_age(self):
> return self.age
> pax=pet
> pax.set_age(4)
> 
> Traceback (most recent call last):
>   File "C:\Functions\test.py", line 18, in 
> pax.set_age(4)
> TypeError: set_age() missing 1 required positional argument: 'age'
> 
> I am trying to pass 4 as the age.  Obviously I am doing it wrong.

The line `pax=pet` doesn't create an instance of your pet class, it creates 
essentially a copy of the class definition.

You need `pax=pet()`

Or preferably, `pax = pet()`.  The spaces are optional, but they make it more 
readable.
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Re: Classes

[Seymore4Head]

On Thu, 30 Oct 2014 13:34:04 -0700, Rob Gaddi
 wrote:

>On Thu, 30 Oct 2014 16:16:51 -0400
>Seymore4Head  wrote:
>
>> class pet: 
>> def set_age(self,age):
>> self.age=age
>> def get_age(self):
>> return self.age
>> pax=pet
>> pax.set_age(4)
>> 
>> Traceback (most recent call last):
>>   File "C:\Functions\test.py", line 18, in 
>> pax.set_age(4)
>> TypeError: set_age() missing 1 required positional argument: 'age'
>> 
>> I am trying to pass 4 as the age.  Obviously I am doing it wrong.
>> 
>
>The reason your call is missing the positional argument is that 4 is
>being assigned to self, rather than to age, so there is no age.  This is
>because you are trying to call a function of the class object, rather
>than a function of an instance of the class.
>
>pax=pet()
Thanks
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Re: Classes

[Seymore4Head]

On Thu, 30 Oct 2014 13:33:01 -0700 (PDT), sohcahto...@gmail.com wrote:

>On Thursday, October 30, 2014 1:19:57 PM UTC-7, Seymore4Head wrote:
>> class pet: 
>> def set_age(self,age):
>> self.age=age
>> def get_age(self):
>> return self.age
>> pax=pet
>> pax.set_age(4)
>> 
>> Traceback (most recent call last):
>>   File "C:\Functions\test.py", line 18, in 
>> pax.set_age(4)
>> TypeError: set_age() missing 1 required positional argument: 'age'
>> 
>> I am trying to pass 4 as the age.  Obviously I am doing it wrong.
>
>The line `pax=pet` doesn't create an instance of your pet class, it creates 
>essentially a copy of the class definition.
>
>You need `pax=pet()`
>
>Or preferably, `pax = pet()`.  The spaces are optional, but they make it more 
>readable.

Thanks
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Re: Classes

[Larry Hudson]

On 10/30/2014 01:16 PM, Seymore4Head wrote:

class pet:
 def set_age(self,age):
 self.age=age
 def get_age(self):
 return self.age
pax=pet
pax.set_age(4)

Traceback (most recent call last):
   File "C:\Functions\test.py", line 18, in 
 pax.set_age(4)
TypeError: set_age() missing 1 required positional argument: 'age'

I am trying to pass 4 as the age.  Obviously I am doing it wrong.

You have already received the answer -- pax=pet should be pax=pet(), but I have a simple 
side-comment about style.  It is common Python convention to capitalize class names, IOW make 
this class Pet instead of class pet.  This is convention not a requirement, but it does help 
distinguish class names from ordinary variable names -- especially to others reading your code 
(as well as yourself a few days later).   ;-)


 -=- Larry -=-

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Re: Classes

[Seymore4Head]

On Thu, 30 Oct 2014 14:28:19 -0700, Larry Hudson 
wrote:

>On 10/30/2014 01:16 PM, Seymore4Head wrote:
>> class pet:
>>  def set_age(self,age):
>>  self.age=age
>>  def get_age(self):
>>  return self.age
>> pax=pet
>> pax.set_age(4)
>>
>> Traceback (most recent call last):
>>File "C:\Functions\test.py", line 18, in 
>>  pax.set_age(4)
>> TypeError: set_age() missing 1 required positional argument: 'age'
>>
>> I am trying to pass 4 as the age.  Obviously I am doing it wrong.
>>
>You have already received the answer -- pax=pet should be pax=pet(), but I 
>have a simple 
>side-comment about style.  It is common Python convention to capitalize class 
>names, IOW make 
>this class Pet instead of class pet.  This is convention not a requirement, 
>but it does help 
>distinguish class names from ordinary variable names -- especially to others 
>reading your code 
>(as well as yourself a few days later).   ;-)
>
>  -=- Larry -=-

I try to take typing shortcuts and it bites me in the behind.
Good suggestion
Thanks
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Saving a file "in the background" -- How?

[Virgil Stokes]

While running a python program I need to save some of the data that is 
being created. I would like to save the data to a file on a disk 
according to a periodical schedule  (e.g. every 10 minutes). Initially, 
the amount of data is small (< 1 MB) but after sometime the amount of 
data can be >10MB. If a problem occurs during data creation, then the 
user should be able to start over from the last successfully saved data.


For my particular application, no other file is being saved and the data 
should always replace (not be appended to) the previous data saved. It 
is important that  the data be saved without any obvious distraction to 
the user who is busy creating more data. That is, I would like to save 
the data "in the background".


What is a good method to perform this task using Python 2.7.8 on a Win32 
platform?

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Re: When using a decorator exceptions raised reference the decorator not the function

[Néstor Boscán]

Thanks Terry

Yes both lines where in the traceback using tb_next I got what I needed.

Regards,

Néstor

On Thu, Oct 30, 2014 at 1:36 PM, Terry Reedy  wrote:

> On 10/30/2014 8:33 AM, Néstor Boscán wrote:
>
>  I'm using Python 2.7 and I'm creating a class decorator that extract
>> information from exceptions for logging purposes.
>>
>> Everytime an exception is raised from the original function and I
>> extract the origin of the exception with sys.exc_info() I get a
>> reference to the line in the decorator where the function is called, not
>> the line of the original function where the exception was raised.
>>
>
> I expect that both lines should be in the traceback.  Post an example
> where you do not intercept the exception.
>
> --
> Terry Jan Reedy
>
>
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>
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Re: Saving a file "in the background" -- How?

[Joel Goldstick]

On Thu, Oct 30, 2014 at 5:30 PM, Virgil Stokes  wrote:
> While running a python program I need to save some of the data that is being
> created. I would like to save the data to a file on a disk according to a
> periodical schedule  (e.g. every 10 minutes). Initially, the amount of data
> is small (< 1 MB) but after sometime the amount of data can be >10MB. If a
> problem occurs during data creation, then the user should be able to start
> over from the last successfully saved data.
>
> For my particular application, no other file is being saved and the data
> should always replace (not be appended to) the previous data saved. It is
> important that  the data be saved without any obvious distraction to the
> user who is busy creating more data. That is, I would like to save the data
> "in the background".
>
> What is a good method to perform this task using Python 2.7.8 on a Win32
> platform?
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I've not tried this, but stackoverflow has a solution that looks like
it could work for you:
http://stackoverflow.com/questions/16214736/write-data-to-disk-in-python-as-a-background-process

-- 
Joel Goldstick
http://joelgoldstick.com
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Re: Python Style Question

[Steven D'Aprano]

MRAB wrote:

> On 2014-10-30 11:10, Steven D'Aprano wrote:
>> Anton wrote:
>>
>>> Let's say I have an incoming list of values *l*. Every element of *l*
>>> can be one of the following options:
>>> 1) an integer value
>>> 2) a string in form of '', e.g. '7'
>>> 3) a string with a json serialization of an integer value, e.g. '"7"'
>>> 4) something else that should be ignored
>>>
>>> I need to transform this list into another list with values from options
>>> 1)-3) coerced to int. The code below should do this.
>>
>> I don't particularly like either version. I prefer this:
>>
>> def load_int(obj):
>>  if isinstance(obj, int):
>>  # Case 1), an int, e.g. 7
>>  return obj
>>  elif isinstance(obj, str):
>>  # Case 2) and 3), a str or JSON serialised int.
>>  # E.g. '7' or '"7"'.
>>  try:
>>  return int(obj)
>>  except ValueError:
>>  return int(json.loads(obj))
>>  raise TypeError('require int or str, got %s' % type(obj).__name__)
>>
> [snip]
> 
> How about:
> 
> int(str(obj).strip('"'))

Absolutely not.

obj = '""1\n\n\n\n'  # not valid JSON
load_int(obj)
=> raises ValueError
int(str(obj).strip('"'))
=> wrongly returns 1


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Steven

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Re: problem with pefile

[Cameron Simpson]

On 29Oct2014 08:34, gandal...@mail.com  wrote:

OT: how can I hide my email in these posts?
Every time I try to send a post, google warns me that my email is visible and 
so I edit it out.


Why would you want to hide your email?

Cameron Simpson 
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Re: Python Style Question

[Roy Smith]

In article <54521c8f$0$12982$c3e8da3$54964...@news.astraweb.com>,
 Steven D'Aprano  wrote:

> Anton wrote:
> 
> > Let's say I have an incoming list of values *l*. Every element of *l* can
> > be one of the following options: 
> > 1) an integer value 
> > 2) a string in form of '', e.g. '7'
> > 3) a string with a json serialization of an integer value, e.g. '"7"'
> > 4) something else that should be ignored
> > 
> > I need to transform this list into another list with values from options
> > 1)-3) coerced to int. The code below should do this.
> 
> I don't particularly like either version. I prefer this:
> 
> def load_int(obj):
> if isinstance(obj, int):
> # Case 1), an int, e.g. 7
> return obj
> elif isinstance(obj, str):
> # Case 2) and 3), a str or JSON serialised int.
> # E.g. '7' or '"7"'.
> try:
> return int(obj)
> except ValueError:
> return int(json.loads(obj))
> raise TypeError('require int or str, got %s' % type(obj).__name__)

Depending on how strictly you're trying to do input validation, the 
int(json.loads(obj)) may not be what you want.  It allows well-formed 
json encoding floats, for example.

And, of course, since

>>> isinstance(True, int)
True

this code accepts booleans.  Oh, but wait, that's by design :-)
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Re: problem with pefile

[Kiuhnm]

On Friday, October 31, 2014 1:33:07 AM UTC+1, Cameron Simpson wrote:
> On 29Oct2014 08:34, gandalf23 wrote:
> >OT: how can I hide my email in these posts?
> >Every time I try to send a post, google warns me that my email is visible 
> >and so I edit it out.
> 
> Why would you want to hide your email?
> 
> Cameron Simpson 

I don't want more spam.
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Re: problem with pefile

[Cameron Simpson]

On 30Oct2014 17:58, Kiuhnm  wrote:

On Friday, October 31, 2014 1:33:07 AM UTC+1, Cameron Simpson wrote:

On 29Oct2014 08:34, gandalf23 wrote:
>OT: how can I hide my email in these posts?
>Every time I try to send a post, google warns me that my email is visible and 
so I edit it out.

Why would you want to hide your email?


I don't want more spam.


You just need to filter your email better.
Most of us do not hide our addresses.

I manage to filter most of my spam by filing anything which gets past all my 
rules that catch mailing lists and which do not come from addresses in my 
"known" group into a probably-spam folder. It is surprisingly effective.


Basicly:
  - to me (me in to/cc/bcc), from a "known" author ==> inbox
  - matches one of my mailing list rules ==> appropriate-folder
  - otherwise ==> probably-spam

That is a simplification, but it is my basic scheme. Works fairly well.

Anyway, this is off-topic for python-list so I'll shut up now.

Cheers,
Cameron Simpson 

It must be public fact, because I'm not the only one who knows about it.
- Stefan A. Werner 
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set environmental variable from python

[Artur Bercik]

I have to set environmental variable in my windows PC as follows:

variable name: GISBASE

value: C:\GRASS-64

Is it possible to set it from python?

import sys

sys.path.append("C:\\GRASS-64")

But how to give variable name? I have to set both the variable name and
value.

Thanks in the advance.

Artur
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Re: Classes

[sohcahtoa82]

On Thursday, October 30, 2014 2:37:54 PM UTC-7, Seymore4Head wrote:
> On Thu, 30 Oct 2014 14:28:19 -0700, Larry Hudson 
> wrote:
> 
> >On 10/30/2014 01:16 PM, Seymore4Head wrote:
> >> class pet:
> >>  def set_age(self,age):
> >>  self.age=age
> >>  def get_age(self):
> >>  return self.age
> >> pax=pet
> >> pax.set_age(4)
> >>
> >> Traceback (most recent call last):
> >>File "C:\Functions\test.py", line 18, in 
> >>  pax.set_age(4)
> >> TypeError: set_age() missing 1 required positional argument: 'age'
> >>
> >> I am trying to pass 4 as the age.  Obviously I am doing it wrong.
> >>
> >You have already received the answer -- pax=pet should be pax=pet(), but I 
> >have a simple 
> >side-comment about style.  It is common Python convention to capitalize 
> >class names, IOW make 
> >this class Pet instead of class pet.  This is convention not a requirement, 
> >but it does help 
> >distinguish class names from ordinary variable names -- especially to others 
> >reading your code 
> >(as well as yourself a few days later).   ;-)
> >
> >  -=- Larry -=-
> 
> I try to take typing shortcuts and it bites me in the behind.
> Good suggestion
> Thanks

A shortcut is the fastest way to get somewhere you weren't going.

Python makes programming very easy (Compared to C/C++ and many other 
languages), but there are still a lot of shortcuts you can't make.
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ANN: Antipathy v0.8

[Ethan Furman]

has just been made compatible with Python 3!  It runs on everything from 2.4 forward, haven't testing anything prior to 
that.


It is available for download at https://pypi.python.org//pypi/antipathy

---

Antipathy -- for those tired of ``os.path``
===

Tired of calling a function for every path manipulation you need to do?

Is:

>>> path, filename = os.path.split(some_name)
>>> basename, ext = os.path.splitext(filename)
>>> basename = basename + '_01'
>>> new_name = os.path.join(path, basename+ext)

wearing on your nerves?

In short, are you filled with antipathy [1] for os.path?

Then get antipathy and work with Path:

>>> some_name = Path('/home/ethan/source/my_file.txt')
>>> backups = Path('/home/ethan/backup/')
>>> print some_name.path
'/home/ethan/source/'
>>> print some_name.ext
'.txt'
>>> print some_name.exists()
True  # (well, if it happens to exist at this moment ;)
>>> backup = backups / some_name.filename + '_01' + some_name.ext
>>> print backup
'/home/ethan/backup/my_file_01.txt'
>>> some_name.copy(backup)

Because Path is a subclass of bytes/str/unicode, it can still be passed to other functions that expect a 
bytes/str/unicode object and work seamlessly [2].


[1] https://www.google.com/#q=antipathy

[2] in most cases -- there are a few places that do a `type` check instead of 
an `isinstance` check.
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Re: Saving a file "in the background" -- How?

[Deepfriedice]

Why not just call the save function as a separate thread?
threading.Thread(target=save, args=(data)).start()
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Re: set environmental variable from python

[Dave Angel]

On 10/30/2014 09:22 PM, Artur Bercik wrote:

I have to set environmental variable in my windows PC as follows:

variable name: GISBASE

value: C:\GRASS-64

Is it possible to set it from python?


Which Python?  I'll have to assume 3.x



import sys

sys.path.append("C:\\GRASS-64")

But how to give variable name? I have to set both the variable name and
value.



sys.path has nothing to do with an environment variable of GISBASE.

Instead you could look up os.environ at:

  https://docs.python.org/3/library/os.html

Also see os.getenv and os.setenv.



Note that it's not necessarily supported.  But I believe it is for a 
standard build on Windows.


Next question is what you hope to achieve by setting such a variable. 
You do realize that it will vanish again when your python process ends? 
 So if you're just planning to use it in your own code, I'd recommend 
finding another method of saving the name & value.


The only value I can see is if you plan to create a subprocess from your 
Python code.


--
DaveA
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Re: Saving a file "in the background" -- How?

[Terry Reedy]

On 10/30/2014 6:21 PM, Joel Goldstick wrote:

On Thu, Oct 30, 2014 at 5:30 PM, Virgil Stokes  wrote:

While running a python program I need to save some of the data that is being
created. I would like to save the data to a file on a disk according to a
periodical schedule  (e.g. every 10 minutes). Initially, the amount of data
is small (< 1 MB) but after sometime the amount of data can be >10MB. If a
problem occurs during data creation, then the user should be able to start
over from the last successfully saved data.

For my particular application, no other file is being saved and the data
should always replace (not be appended to) the previous data saved. It is
important that  the data be saved without any obvious distraction to the
user who is busy creating more data. That is, I would like to save the data
"in the background".

What is a good method to perform this task using Python 2.7.8 on a Win32
platform?
--
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I've not tried this, but stackoverflow has a solution that looks like
it could work for you:
http://stackoverflow.com/questions/16214736/write-data-to-disk-in-python-as-a-background-process


Python 3.4 should have an asyncio solution.


--
Terry Jan Reedy

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Re: set environmental variable from python

[Artur Bercik]

Dear Dave Angel

Thanks for your answer.

I am using Python 2.7

I want to set it permanently.
I have to set several variables so it would be easier if I could set them
from Python.

Hearing the solution.

On Fri, Oct 31, 2014 at 10:50 AM, Dave Angel  wrote:

> On 10/30/2014 09:22 PM, Artur Bercik wrote:
>
>> I have to set environmental variable in my windows PC as follows:
>>
>> variable name: GISBASE
>>
>> value: C:\GRASS-64
>>
>> Is it possible to set it from python?
>>
>
> Which Python?  I'll have to assume 3.x
>
>
>> import sys
>>
>> sys.path.append("C:\\GRASS-64")
>>
>> But how to give variable name? I have to set both the variable name and
>> value.
>>
>>
> sys.path has nothing to do with an environment variable of GISBASE.
>
> Instead you could look up os.environ at:
>
>   https://docs.python.org/3/library/os.html
>
> Also see os.getenv and os.setenv.
>
>
>
> Note that it's not necessarily supported.  But I believe it is for a
> standard build on Windows.
>
> Next question is what you hope to achieve by setting such a variable. You
> do realize that it will vanish again when your python process ends?  So if
> you're just planning to use it in your own code, I'd recommend finding
> another method of saving the name & value.
>
> The only value I can see is if you plan to create a subprocess from your
> Python code.
>
> --
> DaveA
> --
> https://mail.python.org/mailman/listinfo/python-list
>
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Re: set environmental variable from python

[Zachary Ware]

On Thursday, October 30, 2014, Artur Bercik  wrote:

> Dear Dave Angel
>
> Thanks for your answer.
>
> I am using Python 2.7
>
> I want to set it permanently.
> I have to set several variables so it would be easier if I could set them
> from Python.
>

Depending on how "permanently" you mean, about your only solutions would be
"os.system('setx <...>')" or manually manipulating the registry with the
_winreg module.

Hope this helps,
--
Zach


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Re: set environmental variable from python

[Rustom Mody]

On Friday, October 31, 2014 8:01:08 AM UTC+5:30, Zachary Ware wrote:
> On Thursday, October 30, 2014, Artur Bercik  wrote:
> 
> Dear Dave Angel
> 
> 
> Thanks for your answer.
> 
> 
> I am using Python 2.7
> 
> 
> I want to set it permanently.
> I have to set several variables so it would be easier if I could set them 
> from Python.
> 
> 
> Depending on how "permanently" you mean, about your only solutions
> would be "os.system('setx <...>')" or manually manipulating the
> registry with the _winreg module.

Or dont do it from python but directly with regedit??

The question really is: Why do you wish to do this from within python?


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Re: set environmental variable from python

[Artur Bercik]

could you please elaborate 'setx <...>'?


On Fri, Oct 31, 2014 at 11:30 AM, Zachary Ware <
zachary.ware+pyl...@gmail.com> wrote:

> On Thursday, October 30, 2014, Artur Bercik  wrote:
>
>> Dear Dave Angel
>>
>> Thanks for your answer.
>>
>> I am using Python 2.7
>>
>> I want to set it permanently.
>> I have to set several variables so it would be easier if I could set them
>> from Python.
>>
>
> Depending on how "permanently" you mean, about your only solutions would
> be "os.system('setx <...>')" or manually manipulating the registry with the
> _winreg module.
>
> Hope this helps,
> --
> Zach
>
>
> --
> Sent from Gmail Mobile
>
> --
> https://mail.python.org/mailman/listinfo/python-list
>
>
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Re: set environmental variable from python

[Artur Bercik]

I have to set several variables so it would be easier if I could set them
from Python.

On Fri, Oct 31, 2014 at 11:36 AM, Rustom Mody  wrote:

> On Friday, October 31, 2014 8:01:08 AM UTC+5:30, Zachary Ware wrote:
> > On Thursday, October 30, 2014, Artur Bercik  wrote:
> >
> > Dear Dave Angel
> >
> >
> > Thanks for your answer.
> >
> >
> > I am using Python 2.7
> >
> >
> > I want to set it permanently.
> > I have to set several variables so it would be easier if I could set
> them from Python.
> >
> >
> > Depending on how "permanently" you mean, about your only solutions
> > would be "os.system('setx <...>')" or manually manipulating the
> > registry with the _winreg module.
>
> Or dont do it from python but directly with regedit??
>
> The question really is: Why do you wish to do this from within python?
>
>
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> https://mail.python.org/mailman/listinfo/python-list
>
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Re: set environmental variable from python

[Rustom Mody]

On Friday, October 31, 2014 7:33:43 AM UTC+5:30, Artur Bercik wrote:
> Dear Dave Angel
> 
> 
> Thanks for your answer.
> 
> 
> I am using Python 2.7
> 
> 
> I want to set it permanently.
> I have to set several variables so it would be easier if I could set them 
> from Python.

regedit is scriptable
http://support.microsoft.com/kb/310516

[Be careful though! Follow the precautions like backing up the registry
before messing around]
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Re: set environmental variable from python

[Zachary Ware]

On Thu, Oct 30, 2014 at 9:40 PM, Artur Bercik  wrote:
> could you please elaborate 'setx <...>'?

>From a Command Prompt, do 'help setx' for details on how to use setx.

Rustom's suggestion of using regedit is going to be far easier than
using _winreg (which probably shouldn't even be considered as an
option).  Using `os.system('setx ...')` is going to be the easiest way
to do things if you have to calculate the values of your variables,
but if you just have a bunch of values that you're going to have to
key in anyway, just use setx directly (or in a batch script).

-- 
Zach
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Re: Python Style Question

[Steven D'Aprano]

Roy Smith wrote:

> In article <54521c8f$0$12982$c3e8da3$54964...@news.astraweb.com>,
>  Steven D'Aprano  wrote:
> 
>> Anton wrote:
>> 
>> > Let's say I have an incoming list of values *l*. Every element of *l*
>> > can be one of the following options:
>> > 1) an integer value
>> > 2) a string in form of '', e.g. '7'
>> > 3) a string with a json serialization of an integer value, e.g. '"7"'
>> > 4) something else that should be ignored
>> > 
>> > I need to transform this list into another list with values from
>> > options 1)-3) coerced to int. The code below should do this.
>> 
>> I don't particularly like either version. I prefer this:
>> 
>> def load_int(obj):
>> if isinstance(obj, int):
>> # Case 1), an int, e.g. 7
>> return obj
>> elif isinstance(obj, str):
>> # Case 2) and 3), a str or JSON serialised int.
>> # E.g. '7' or '"7"'.
>> try:
>> return int(obj)
>> except ValueError:
>> return int(json.loads(obj))
>> raise TypeError('require int or str, got %s' % type(obj).__name__)
> 
> Depending on how strictly you're trying to do input validation, the
> int(json.loads(obj)) may not be what you want.  It allows well-formed
> json encoding floats, for example.

Really?

py> int(json.loads(json.dumps(23.5)))
23

Damn! You're right.

Back to Plan A:

elif isinstance(obj, str):
try:
return int(obj)
except ValueError:
if obj and obj.startswith('"') and obj.endswith('"'):
return int(obj[1:-1])
raise


But of course even the int() function itself may be a little more flexible
than we might want:

py> int('1')
1


So I guess the lessons are:

* before writing code, you need to decide what the code is meant to do;

* and that includes what input must be rejected, not just what input 
  must be accepted.


> And, of course, since
> 
 isinstance(True, int)
> True
> 
> this code accepts booleans.  Oh, but wait, that's by design :-)

Naturally :-)

If you wanted to avoid it, that's easy, add a clause:

if isinstance(obj, bool):
raise TypeError

at the start of the function.


-- 
Steven

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Re: Python Style Question

[Denis McMahon]

On Fri, 31 Oct 2014 09:48:10 +1100, Steven D'Aprano wrote:

> MRAB wrote:

>> How about:
>> 
>> int(str(obj).strip('"'))
> 
> Absolutely not.
> 
> obj = '""1\n\n\n\n'  # not valid JSON load_int(obj)
> => raises ValueError int(str(obj).strip('"'))
> => wrongly returns 1

How about

#!/usr/bin/python

import re, json

l = [1, -1, 0, '+2', '2', '-2', '0', '"+3"', '"3"', '"-3"', '"0"', 
 json.dumps(-4), json.dumps(4), json.dumps(0), 
 'x', 'sqjklsqjk__', (5, 6), 
 7.7, -7.7, '8.8', '+8.8', '-8.8', '"9.9"', '"+9.9"', '"-9.9"']

patt1 = re.compile(r'^([-+]?\d+)$')
patt2 = re.compile(r'^"([-+]?\d+)"$')

def getTheInt(x):

if isinstance(x,int):
return x

if isinstance(x,str):
tmp = patt1.match(x)

if tmp:
return int(tmp.group(1))

tmp = patt2.match(x)

if tmp:
return int(tmp.group(1))

return None

a = []

for n in l:
a.append(getTheInt(n))

print a

# end of code

prints:

[1, -1, 0, 2, 2, -2, 0, 3, 3, -3, 0, -4, 4, 0, None, None, None, None, 
None, None, None, None, None, None, None]

I know re matching the strings may be overkill, but it may be the best 
way of checking that the string contains the expected character format to 
convert to an int.

-- 
Denis McMahon, denismfmcma...@gmail.com
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