Re: variable hell
[EMAIL PROTECTED] wrote: > Steve, can I quote you on that? > > "You can lead an idiot to idioms, but you can't make him think!" -- > Steve Holden 2005 > Looks like you just did :-). Feel free. regards Steve -- Steve Holden +44 150 684 7255 +1 800 494 3119 Holden Web LLC http://www.holdenweb.com/ -- http://mail.python.org/mailman/listinfo/python-list
Re: variable hell
Steve, can I quote you on that? "You can lead an idiot to idioms, but you can't make him think!" -- Steve Holden 2005 -- http://mail.python.org/mailman/listinfo/python-list
Re: variable hell
Fredrik Lundh wrote: > Steve Holden wrote: > > >>Yes. A large part of learning a language is discovering the many idioms >>that have already been established for doing certain things. These are a >>kind of shorthand, established by long convention, that allow one to >>avoid the "learning-by-use" curve. > > > it's not obvious that the OP has found the pydiomatic way to solve > his problem, though, given that most of this thread have been spent > on playing with exec, and that Robert Kern's question from the be- > ginning of this thread has still not been answered: > > "Again, why unpack them into separate variables when they are *already* > in the form that you want to use them?" > Fair enough. I was trying to advocate the use of the suggested idioms, but some people seem to insist on going their own way even when it leads to a collision wiht a bricj wall. You can lead an idiot to idioms, but you can't make him think ;-) regards Steve -- Steve Holden +44 150 684 7255 +1 800 494 3119 Holden Web LLC http://www.holdenweb.com/ -- http://mail.python.org/mailman/listinfo/python-list
Re: variable hell
What you could do is to create a class for this; fill it's __dict__ instance; and use custom getattr() / setattr() methods for accessing a0, a1, a2 etc. cheers, --Tim -- http://mail.python.org/mailman/listinfo/python-list
Re: variable hell
Steve Holden wrote: > Yes. A large part of learning a language is discovering the many idioms > that have already been established for doing certain things. These are a > kind of shorthand, established by long convention, that allow one to > avoid the "learning-by-use" curve. it's not obvious that the OP has found the pydiomatic way to solve his problem, though, given that most of this thread have been spent on playing with exec, and that Robert Kern's question from the be- ginning of this thread has still not been answered: "Again, why unpack them into separate variables when they are *already* in the form that you want to use them?" -- http://mail.python.org/mailman/listinfo/python-list
Re: variable hell
Oops, you're completely right. I'm sorry, it is indeed my mistake. I was thinking people were telling me I was quoting Martin wrong, while I was quoting Rafi wrong. I'll promise not quote anybody anymore until I have an e-mail program that can quote/copy properly. As reading it in one window, then typing it in another to test it, then copying it back, obviously introduced a PEBKAC error. Adriaan Renting -- http://mail.python.org/mailman/listinfo/python-list
Re: variable hell
Adriaan Renting wrote:
> My original code was: exec(eval("'a%s=%s' % (count, value)"))
> Then Rafi said: exec("'a%s=%s' % (count, value)")
> To which I responded that his example does not work in my Python, and I think
> it's invalid.
> Then Martin came with: exec 'a%s = %s' % (count, value)
> This does work.
> But he seems to keep telling me I'm quoting him wrong, while I'm quoting Rafi.
Read more carefully. rafi did not put in the extraneous quotes.
rafi:
>>Adriaan Renting wrote:
>>
>>>You might be able to do something along the lines of
>>>
>>>for count in range(0,maxcount):
>>>value = values[count]
>>>exec(eval("'a%s=%s' % (count, value)"))
>>
>>why using the eval?
>>
>>exec ('a%s=%s' % (count, value))
>>
>>should be fine
>>
>>--
>>rafi
See? No extra quotes.
--
Robert Kern
[EMAIL PROTECTED]
"In the fields of hell where the grass grows high
Are the graves of dreams allowed to die."
-- Richard Harter
--
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Re: variable hell
I'm sorry for top-posting and not marking quoted text, but my e-mail reader
(Novell Groupwise 6 for Linux) does not mark quoted text. The only thing it
does is the >>> $NAME <$EMAIL> $DATE >>> above the quoted text. Therefore I add
my comments at the top. The only alternative I have is copying all text to an
editor, adding quote marks by hand, then copying it back into a new e-mail
message, but this takes to much of m time. If this is to confusing I will just
stop posting in this list.
My original code was: exec(eval("'a%s=%s' % (count, value)"))
Then Rafi said: exec("'a%s=%s' % (count, value)")
To which I responded that his example does not work in my Python, and I think
it's invalid.
Then Martin came with: exec 'a%s = %s' % (count, value)
This does work.
But he seems to keep telling me I'm quoting him wrong, while I'm quoting Rafi.
Furthermore I'm going with your suggestion of checking the imp, globals() and
locals().
Adriaan Renting.
>>>Mike Meyer <[EMAIL PROTECTED]> 08/27/05 2:24 am >>>
[The context is totally hosed by top posting and failure to mark
quoted text. I gave up on recovering it.]
"Adriaan Renting" <[EMAIL PROTECTED]> writes:
>Not in my Python.
>
for count in range(0, 10):
>... value = count
>... exec("'a%s=%s' % (count, value)")
You left in the extra set of quotes. Try this:
>>>for count in range(10):
... value = count
... exec 'a%s = %s' % (count, value)
...
>>>dir()
['__builtins__', '__doc__', '__file__', '__name__', 'a0', 'a1', 'a2', 'a3',
'a4', 'a5', 'a6', 'a7', 'a8', 'a9', 'count', 'help', 'readline', 'rlcompleter',
'sys', 'value']
I also removed the extraneous parens that you and Rafi both used -
exec is a statement, not a function.
Of course, your two examples are better done using imp and globals() or
locals().
>>>dir()
>['__builtins__', '__doc__', '__name__', 'count', 'value']
for count in range(0, 10):
>... value = count
>... exec(eval("'a%s=%s' % (count, value)"))
>...
dir()
>['__builtins__', '__doc__', '__name__', 'a0', 'a1', 'a2', 'a3', 'a4', 'a5',
>'a6', 'a7', 'a8', 'a9', 'count', 'value']
>
>I myself use code like this to load user defined classes.
>exec(eval("'from %s import %s' % (script, script)"))
>exec(eval("'self.user_class = %s()' % script"))
>self.user_class.run()
>
>But this can probably be done with the imp module too.
>
rafi <[EMAIL PROTECTED]> 08/25/05 6:03 pm >>>
>Adriaan Renting wrote:
>>You might be able to do something along the lines of
>>
>>for count in range(0,maxcount):
>> value = values[count]
>> exec(eval("'a%s=%s' % (count, value)"))
>
>why using the eval?
>
>exec ('a%s=%s' % (count, value))
>
>should be fine
>
>--
>rafi
>
>"Imagination is more important than knowledge."
> (Albert Einstein)
>--
>http://mail.python.org/mailman/listinfo/python-list
>
--
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Re: variable hell
[The context is totally hosed by top posting and failure to mark
quoted text. I gave up on recovering it.]
"Adriaan Renting" <[EMAIL PROTECTED]> writes:
> Not in my Python.
>
for count in range(0, 10):
> ... value = count
> ... exec("'a%s=%s' % (count, value)")
You left in the extra set of quotes. Try this:
>>> for count in range(10):
... value = count
... exec 'a%s = %s' % (count, value)
...
>>> dir()
['__builtins__', '__doc__', '__file__', '__name__', 'a0', 'a1', 'a2', 'a3',
'a4', 'a5', 'a6', 'a7', 'a8', 'a9', 'count', 'help', 'readline', 'rlcompleter',
'sys', 'value']
I also removed the extraneous parens that you and Rafi both used -
exec is a statement, not a function.
Of course, your two examples are better done using imp and globals() or
locals().
>>> dir()
> ['__builtins__', '__doc__', '__name__', 'count', 'value']
for count in range(0, 10):
> ... value = count
> ... exec(eval("'a%s=%s' % (count, value)"))
> ...
dir()
> ['__builtins__', '__doc__', '__name__', 'a0', 'a1', 'a2', 'a3', 'a4', 'a5',
> 'a6', 'a7', 'a8', 'a9', 'count', 'value']
>
> I myself use code like this to load user defined classes.
> exec(eval("'from %s import %s' % (script, script)"))
> exec(eval("'self.user_class = %s()' % script"))
> self.user_class.run()
>
> But this can probably be done with the imp module too.
>
rafi <[EMAIL PROTECTED]> 08/25/05 6:03 pm >>>
> Adriaan Renting wrote:
>>You might be able to do something along the lines of
>>
>>for count in range(0,maxcount):
>> value = values[count]
>> exec(eval("'a%s=%s' % (count, value)"))
>
> why using the eval?
>
> exec ('a%s=%s' % (count, value))
>
> should be fine
>
> --
> rafi
>
> "Imagination is more important than knowledge."
>(Albert Einstein)
> --
> http://mail.python.org/mailman/listinfo/python-list
>
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Re: variable hell
Nx wrote: > Thanks for all the responses and animated discussion, > which is still the best way to learn something new. > > Most of the time it is not that you want to do something > in a certain way , it rather is one cannot think of a > better , faster more efficient way . > > Nx Yes. A large part of learning a language is discovering the many idioms that have already been established for doing certain things. These are a kind of shorthand, established by long convention, that allow one to avoid the "learning-by-use" curve. When I first came to Python that was a very rewarding aspect of this newsgroup. To this day it remains one of the friendliest tech-spots in cyberspace. regards Steve -- Steve Holden +44 150 684 7255 +1 800 494 3119 Holden Web LLC http://www.holdenweb.com/ -- http://mail.python.org/mailman/listinfo/python-list
Re: variable hell
Adriaan Renting wrote:
> Not in my Python.
>
>
for count in range(0, 10):
>
> ... value = count
> ... exec("'a%s=%s' % (count, value)")
But that's not what rafi suggested.
rafi:
> why using the eval?
>
> exec ('a%s=%s' % (count, value))
See the difference?
--
Robert Kern
[EMAIL PROTECTED]
"In the fields of hell where the grass grows high
Are the graves of dreams allowed to die."
-- Richard Harter
--
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Re: variable hell
Benji York schrieb:
>> >>> suffix = 'var'
>> >>> vars()['a%s' % suffix] = 45
>> >>> avar
>> 45
>
>
> Quoting from http://docs.python.org/lib/built-in-funcs.html#l2h-76 about
> the "vars" built in:
>
> The returned dictionary should not be modified: the effects on the
> corresponding symbol table are undefined.
I tried this once and it worked. This may be too naive, so thanks
for the warning :)
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Re: variable hell
Adriaan Renting wrote:
> Not in my Python.
>
>
for count in range(0, 10):
>
> ... value = count
> ... exec("'a%s=%s' % (count, value)")
> ...
>
dir()
>
> ['__builtins__', '__doc__', '__name__', 'count', 'value']
You did not copy the suggestion properly:
>>> for count in range(0, 10):
... exec 'a%s = %s' % (count,count)
...
>>> dir()
['__builtins__', '__doc__', '__file__', '__name__', 'a0', 'a1', 'a2',
'a3', 'a4', 'a5', 'a6', 'a7', 'a8', 'a9', 'count']
>>> a5
5
(you can put additional parentheses around the string, but not
additional quotation marks)
Regards,
Martin
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Re: variable hell
I was responding to rafi's suggestion, I had not received the "exec 'a%s = %s'
% (count,count)" response yet at that time. The "exec 'a%s = %s' %
(count,value)" works fine.
>Not in my Python.
>
>---snip---
>
>why using the eval?
>
>exec ('a%s=%s' % (count, value))
>
>should be fine
>
>--
>rafi
--- I appologize for any top-posting, and improper inlining, I'm using
groupwise ---
>>>"Martin v. Löwis" <[EMAIL PROTECTED]> 08/26/05 10:19 am >>>
Adriaan Renting wrote:
>Not in my Python.
>
>
for count in range(0, 10):
>
>... value = count
>... exec("'a%s=%s' % (count, value)")
>...
>
dir()
>
>['__builtins__', '__doc__', '__name__', 'count', 'value']
You did not copy the suggestion properly:
>>>for count in range(0, 10):
... exec 'a%s = %s' % (count,count)
...
>>>dir()
['__builtins__', '__doc__', '__file__', '__name__', 'a0', 'a1', 'a2',
'a3', 'a4', 'a5', 'a6', 'a7', 'a8', 'a9', 'count']
>>>a5
5
(you can put additional parentheses around the string, but not
additional quotation marks)
Regards,
Martin
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Re: variable hell
Ron Garret wrote: >>Because eval() takes an expression as an argument, and assignment is a >>statement. > > And if you find this distinction annoying, try Lisp. that's were I come from :-) -- rafi "Imagination is more important than knowledge." (Albert Einstein) -- http://mail.python.org/mailman/listinfo/python-list
Re: variable hell
Not in my Python.
>>> for count in range(0, 10):
... value = count
... exec("'a%s=%s' % (count, value)")
...
>>> dir()
['__builtins__', '__doc__', '__name__', 'count', 'value']
>>> for count in range(0, 10):
... value = count
... exec(eval("'a%s=%s' % (count, value)"))
...
>>> dir()
['__builtins__', '__doc__', '__name__', 'a0', 'a1', 'a2', 'a3', 'a4', 'a5',
'a6', 'a7', 'a8', 'a9', 'count', 'value']
>>>
I myself use code like this to load user defined classes.
exec(eval("'from %s import %s' % (script, script)"))
exec(eval("'self.user_class = %s()' % script"))
self.user_class.run()
But this can probably be done with the imp module too.
>>>rafi <[EMAIL PROTECTED]> 08/25/05 6:03 pm >>>
Adriaan Renting wrote:
>You might be able to do something along the lines of
>
>for count in range(0,maxcount):
> value = values[count]
> exec(eval("'a%s=%s' % (count, value)"))
why using the eval?
exec ('a%s=%s' % (count, value))
should be fine
--
rafi
"Imagination is more important than knowledge."
(Albert Einstein)
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Re: variable hell
Thanks for all the responses and animated discussion, which is still the best way to learn something new. Most of the time it is not that you want to do something in a certain way , it rather is one cannot think of a better , faster more efficient way . Nx -- http://mail.python.org/mailman/listinfo/python-list
Re: variable hell
In article <[EMAIL PROTECTED]>,
Steve Holden <[EMAIL PROTECTED]> wrote:
> rafi wrote:
> > Reinhold Birkenfeld wrote:
> >
> >
> exec(eval("'a%s=%s' % (count, value)"))
> >>>
> >>>why using the eval?
> >>>
> >>>exec ('a%s=%s' % (count, value))
> >>>
> >>>should be fine
> >>
> >>And this demonstrates why exec as a statement was a mistake ;)
> >>
> >>It actually is
> >>
> >>exec 'a%s=%s' % (count, value)
> >
> >
> > Noted.
> >
> > In the meantime another question I cannot find an answer to: any idea
> > why does eval() consider '=' as a syntax error?
> >
> > >>> eval ('a=1')
> > Traceback (most recent call last):
> >File "", line 1, in ?
> >File "", line 1
> > a=1
> > ^
> > SyntaxError: invalid syntax
> >
> > Thanks
> >
> Because eval() takes an expression as an argument, and assignment is a
> statement.
And if you find this distinction annoying, try Lisp.
rg
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Re: variable hell
Steve Holden wrote: > Because eval() takes an expression as an argument, and assignment is a > statement. I am definitely not a language lawyer... but I should a little bit more thanks, -- rafi "Imagination is more important than knowledge." (Albert Einstein) -- http://mail.python.org/mailman/listinfo/python-list
Re: variable hell
rafi wrote:
> Reinhold Birkenfeld wrote:
>
>
exec(eval("'a%s=%s' % (count, value)"))
>>>
>>>why using the eval?
>>>
>>>exec ('a%s=%s' % (count, value))
>>>
>>>should be fine
>>
>>And this demonstrates why exec as a statement was a mistake ;)
>>
>>It actually is
>>
>>exec 'a%s=%s' % (count, value)
>
>
> Noted.
>
> In the meantime another question I cannot find an answer to: any idea
> why does eval() consider '=' as a syntax error?
>
> >>> eval ('a=1')
> Traceback (most recent call last):
>File "", line 1, in ?
>File "", line 1
> a=1
> ^
> SyntaxError: invalid syntax
>
> Thanks
>
Because eval() takes an expression as an argument, and assignment is a
statement.
regards
Steve
--
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Holden Web LLC http://www.holdenweb.com/
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Re: variable hell
rafi wrote:
> In the meantime another question I cannot find an answer to: any idea
> why does eval() consider '=' as a syntax error?
>
> >>> eval ('a=1')
> Traceback (most recent call last):
>File "", line 1, in ?
>File "", line 1
> a=1
> ^
> SyntaxError: invalid syntax
eval *evaluates* an expression. "a=1" is a statement. It has no value.
--
Robert Kern
[EMAIL PROTECTED]
"In the fields of hell where the grass grows high
Are the graves of dreams allowed to die."
-- Richard Harter
--
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Re: variable hell
Ron Garret wrote: > In article <[EMAIL PROTECTED]>, > Robert Kern <[EMAIL PROTECTED]> wrote: > >> In the >>bowels of my modules, I may not know what the contents are at code-time, > > Then how do you write your code? With style. ;-) I use a Bunch where I might otherwise use a dictionary inside my modules because it *is* a dictionary. Interactively, I'll usually use it as an object with attributes. The keys are usually ideosyncratic, like station codes for permanent GPS stations (e.g. "CAND", "USLO", "MNMC", "MIDA"), rather than generic (e.g. "northing", "day"). So I might have a function that do some analysis on all of the GPS stations within a Bunch. I don't know the names of the stations when I'm writing the function, but I can iterate over the keys and values in the Bunch. def subtract_reference(data, refstation): """Subtract the motion of the reference station from the remaining timeseries. """ refdata = data[refstation] for station in data: if station == refstation: continue data[station].northing -= refdata.northing data[station].easting -= refdata.easting # ... At the prompt, though, I may want to plot CAND's timeseries. In [10]: plot(data.CAND.t, data.CAND.northing) Bunch allows me to use "data[station]" and "data.CAND" as the situation demands rather than forcing me to use the clunkier "getattr(data, station)" or "data['CAND']", respectively. -- Robert Kern [EMAIL PROTECTED] "In the fields of hell where the grass grows high Are the graves of dreams allowed to die." -- Richard Harter -- http://mail.python.org/mailman/listinfo/python-list
Re: variable hell
Reinhold Birkenfeld wrote:
>>> exec(eval("'a%s=%s' % (count, value)"))
>>
>>why using the eval?
>>
>>exec ('a%s=%s' % (count, value))
>>
>>should be fine
>
> And this demonstrates why exec as a statement was a mistake ;)
>
> It actually is
>
> exec 'a%s=%s' % (count, value)
Noted.
In the meantime another question I cannot find an answer to: any idea
why does eval() consider '=' as a syntax error?
>>> eval ('a=1')
Traceback (most recent call last):
File "", line 1, in ?
File "", line 1
a=1
^
SyntaxError: invalid syntax
Thanks
--
rafi
"Imagination is more important than knowledge."
(Albert Einstein)
--
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Re: variable hell
rafi wrote:
> Adriaan Renting wrote:
>> You might be able to do something along the lines of
>>
>> for count in range(0,maxcount):
>> value = values[count]
>> exec(eval("'a%s=%s' % (count, value)"))
>
> why using the eval?
>
> exec ('a%s=%s' % (count, value))
>
> should be fine
And this demonstrates why exec as a statement was a mistake ;)
It actually is
exec 'a%s=%s' % (count, value)
Reinhold
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Re: variable hell
In article <[EMAIL PROTECTED]>, Robert Kern <[EMAIL PROTECTED]> wrote: > In the > bowels of my modules, I may not know what the contents are at code-time, Then how do you write your code? rg -- http://mail.python.org/mailman/listinfo/python-list
Re: variable hell
[EMAIL PROTECTED] wrote:
> Hey, if the man wants to write it that way, let the man write it that
> way. If it works for him, great... he's sure confused the heck out of
> all of us, and that translates into job security for him! As you can
> see, the name of the post is 'variable hell' and that is exactly what
> he is creating, so "Adriaan Renting", excellent response!
>
http://mindprod.com/jgloss/unmain.html
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Re: variable hell
Carsten Haese wrote: > On Thu, 2005-08-25 at 11:04, I hastily wrote: > >>On Thu, 2005-08-25 at 10:43, Nx wrote: >> >>>Thanks for the many replies >>> >>> here is an example for what it will be used for , in this case >>> fixed at 31 fieldvalues: >>> >>> inputvalues=(s0,s1,s2,s3,s4,s5,s6,s7,s8,s9,s10,s11,s12,s13,s14,s15,s16,s17,s18,s19,s20,s21,s22,s23,s24,s25, >>>s26,s27,s28,s29,s30,s31) >> >>inputvalues = tuple(mylist) > > > And actually, you probably don't have to do that, because the execute > method should be able to handle a list just as well as a tuple. > That depends on the database module. Some will insist in tuples, IIRC. regards Steve -- Steve Holden +44 150 684 7255 +1 800 494 3119 Holden Web LLC http://www.holdenweb.com/ -- http://mail.python.org/mailman/listinfo/python-list
Re: variable hell
Nx wrote: >>""" >> >>Why unpack inputvalues if your next step is to pack'em back again ? Or >>what did I miss ? > > The original values in this case are being read from a text file > with one value including a linefeed per line and the original idea was, > that having them read into a list was the best way to massage them into the > form required to be used as input values for the insert statement. Again, why unpack them into separate variables when they are *already* in the form that you want to use them? -- Robert Kern [EMAIL PROTECTED] "In the fields of hell where the grass grows high Are the graves of dreams allowed to die." -- Richard Harter -- http://mail.python.org/mailman/listinfo/python-list
Re: variable hell
Ron Garret wrote: > If you really want to make something like this work you can define a > class that would work like this: > > vars = funkyclass() > varname = 'x' > vars[varname] = value > vars.x > > But this is clearly a design mistake. Either you know the names of the > variables when you write the code or you do not. If you know them you > can simply assign them directly. If you do not know them then you can't > put them in the code to read their values anyway, and what you need is > just a regular dictionary. In fact, I do this all of the time. class Bunch(dict): def __init__(self, *args, **kwds): dict.__init__(self, *args, **kwds) self.__dict__ = self It's a lifesaver when you're working at the interactive prompt. In the bowels of my modules, I may not know what the contents are at code-time, but at the prompt I probably do. Bunch assists both usages. -- Robert Kern [EMAIL PROTECTED] "In the fields of hell where the grass grows high Are the graves of dreams allowed to die." -- Richard Harter -- http://mail.python.org/mailman/listinfo/python-list
Re: variable hell
In article <[EMAIL PROTECTED]>, Benji York <[EMAIL PROTECTED]> wrote: > Peter Maas wrote: > > >>> suffix = 'var' > > >>> vars()['a%s' % suffix] = 45 > > >>> avar > > 45 > > Quoting from http://docs.python.org/lib/built-in-funcs.html#l2h-76 about > the "vars" built in: > > The returned dictionary should not be modified: the effects on the > corresponding symbol table are undefined. If you really want to make something like this work you can define a class that would work like this: vars = funkyclass() varname = 'x' vars[varname] = value vars.x But this is clearly a design mistake. Either you know the names of the variables when you write the code or you do not. If you know them you can simply assign them directly. If you do not know them then you can't put them in the code to read their values anyway, and what you need is just a regular dictionary. rg -- http://mail.python.org/mailman/listinfo/python-list
Re: variable hell
Adriaan Renting wrote:
> You might be able to do something along the lines of
>
> for count in range(0,maxcount):
> value = values[count]
> exec(eval("'a%s=%s' % (count, value)"))
why using the eval?
exec ('a%s=%s' % (count, value))
should be fine
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"Imagination is more important than knowledge."
(Albert Einstein)
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Re: variable hell
Hey, if the man wants to write it that way, let the man write it that way. If it works for him, great... he's sure confused the heck out of all of us, and that translates into job security for him! As you can see, the name of the post is 'variable hell' and that is exactly what he is creating, so "Adriaan Renting", excellent response! -- http://mail.python.org/mailman/listinfo/python-list
Re: variable hell
> """ > > Why unpack inputvalues if your next step is to pack'em back again ? Or > what did I miss ? > The original values in this case are being read from a text file with one value including a linefeed per line and the original idea was, that having them read into a list was the best way to massage them into the form required to be used as input values for the insert statement. Nx -- http://mail.python.org/mailman/listinfo/python-list
Re: variable hell
On Thu, 2005-08-25 at 11:04, I hastily wrote: > On Thu, 2005-08-25 at 10:43, Nx wrote: > > Thanks for the many replies > > > > here is an example for what it will be used for , in this case > > fixed at 31 fieldvalues: > > > > > > inputvalues=(s0,s1,s2,s3,s4,s5,s6,s7,s8,s9,s10,s11,s12,s13,s14,s15,s16,s17,s18,s19,s20,s21,s22,s23,s24,s25, > > s26,s27,s28,s29,s30,s31) > > inputvalues = tuple(mylist) And actually, you probably don't have to do that, because the execute method should be able to handle a list just as well as a tuple. -Carsten. -- http://mail.python.org/mailman/listinfo/python-list
Re: variable hell
You might be able to do something along the lines of
for count in range(0,maxcount):
value = values[count]
exec(eval("'a%s=%s' % (count, value)"))
But I am also wonder: why?
Peter Maas wrote:
> >>>suffix = 'var'
> >>>vars()['a%s' % suffix] = 45
> >>>avar
>45
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Re: variable hell
On Thu, 2005-08-25 at 10:43, Nx wrote: > Thanks for the many replies > > here is an example for what it will be used for , in this case > fixed at 31 fieldvalues: > > > inputvalues=(s0,s1,s2,s3,s4,s5,s6,s7,s8,s9,s10,s11,s12,s13,s14,s15,s16,s17,s18,s19,s20,s21,s22,s23,s24,s25, > s26,s27,s28,s29,s30,s31) inputvalues = tuple(mylist) Hope this helps, Carsten. -- http://mail.python.org/mailman/listinfo/python-list
Re: variable hell
Nx wrote:
> Thanks for the many replies
>
> here is an example for what it will be used for , in this case
> fixed at 31 fieldvalues:
>
>
> inputvalues=(s0,s1,s2,s3,s4,s5,s6,s7,s8,s9,s10,s11,s12,s13,s14,s15,s16,s17,s18,s19,s20,s21,s22,s23,s24,s25,
> s26,s27,s28,s29,s30,s31)
>MYINSERTSELECT = "INSERT INTO
> ADDRESS(ALIAS,COMPANY,ADDRESSLI1,ADDRESSLI2,ADDRESSCO,TOWN,ZIP,COUNTRY,TEL1,TEL2,FAX,EMAIL,INTERNET,PERSON1,TITLE1,RES1,PERSON2,TITLE2,RES2,PERSON3,TITLE3,RES3,PERSON4,TITLE4,RES4,PERSON5,TITLE5,RES5,PRODALIAS,PAGER,TLX,ADDMEMO)
>VALUES(?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?)"
>
>con1.commit()
>cur = con1.cursor()
>try :
> cur.execute(MYINSERTSELECT,inputvalues)
If I refer to your original post, there's someting I dont understand:
"""
I am unpacking a list into variables, for some reason they need to be
unpacked into variable names like a0,a1,a2upto aN whatever is
in the list.
"""
Why unpack inputvalues if your next step is to pack'em back again ? Or
what did I miss ?
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python -c "print '@'.join(['.'.join([w[::-1] for w in p.split('.')]) for
p in '[EMAIL PROTECTED]'.split('@')])"
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Re: variable hell
Thanks for the many replies here is an example for what it will be used for , in this case fixed at 31 fieldvalues: inputvalues=(s0,s1,s2,s3,s4,s5,s6,s7,s8,s9,s10,s11,s12,s13,s14,s15,s16,s17,s18,s19,s20,s21,s22,s23,s24,s25, s26,s27,s28,s29,s30,s31) MYINSERTSELECT = "INSERT INTO ADDRESS(ALIAS,COMPANY,ADDRESSLI1,ADDRESSLI2,ADDRESSCO,TOWN,ZIP,COUNTRY,TEL1,TEL2,FAX,EMAIL,INTERNET,PERSON1,TITLE1,RES1,PERSON2,TITLE2,RES2,PERSON3,TITLE3,RES3,PERSON4,TITLE4,RES4,PERSON5,TITLE5,RES5,PRODALIAS,PAGER,TLX,ADDMEMO) VALUES(?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?)" con1.commit() cur = con1.cursor() try : cur.execute(MYINSERTSELECT,inputvalues) con1.commit() print 'Inserted 1 record' except IOError, (errno, strerror): print "I/O error(%s): %s" % (errno, strerror) except ValueError: print "Could not convert data to an integer." except: print "Unexpected error:", sys.exc_info()[0] raise I am sure there is an easier way, but I have not found it yet. Nx -- http://mail.python.org/mailman/listinfo/python-list
Re: variable hell
Peter Maas wrote: > >>> suffix = 'var' > >>> vars()['a%s' % suffix] = 45 > >>> avar > 45 Quoting from http://docs.python.org/lib/built-in-funcs.html#l2h-76 about the "vars" built in: The returned dictionary should not be modified: the effects on the corresponding symbol table are undefined. -- Benji York -- http://mail.python.org/mailman/listinfo/python-list
Re: variable hell
Nx schrieb:
> Hi
>
> I am unpacking a list into variables, for some reason they need to be
> unpacked into variable names like a0,a1,a2upto aN whatever is
> in the list.
>
> How to create the variables dynamically ?
>
> I am looking for something like
> pseudo code line follows :
>
> a%s = str(value)
>>> suffix = 'var'
>>> vars()['a%s' % suffix] = 45
>>> avar
45
--
---
Peter Maas, M+R Infosysteme, D-52070 Aachen, Tel +49-241-93878-0
E-mail 'cGV0ZXIubWFhc0BtcGx1c3IuZGU=\n'.decode('base64')
---
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Re: variable hell
Nx enlightened us with: > I am unpacking a list into variables, for some reason they need to > be unpacked into variable names like a0,a1,a2upto aN whatever is > in the list. You're probably doing things the wrong way. What is your ultimate goal with this? There is probably a better way of doing it. In the mean time, look at eval(). Sybren -- The problem with the world is stupidity. Not saying there should be a capital punishment for stupidity, but why don't we just take the safety labels off of everything and let the problem solve itself? Frank Zappa -- http://mail.python.org/mailman/listinfo/python-list
Re: variable hell
"Nx" <[EMAIL PROTECTED]> wrote: > I am unpacking a list into variables, for some reason they need to be > unpacked into variable names like a0,a1,a2upto aN whatever is > in the list. why? -- http://mail.python.org/mailman/listinfo/python-list
Re: variable hell
Nx wrote: > Hi > > I am unpacking a list into variables, for some reason they need to be > unpacked into variable names like a0,a1,a2upto aN whatever is > in the list. Really? Why? -- Robert Kern [EMAIL PROTECTED] "In the fields of hell where the grass grows high Are the graves of dreams allowed to die." -- Richard Harter -- http://mail.python.org/mailman/listinfo/python-list
Re: variable hell
Nx wrote: > I am unpacking a list into variables, for some reason they need to be > unpacked into variable names like a0,a1,a2upto aN whatever is > in the list. Explain this "some reason". This smells, and the way to go would be to use a dict mapping a_n to whatever is in the list - not creating variables. How do you want to access generated variables anyway - especially when you don't have the faintest idea how many of them there are? Obviously there can't be code written based on that. Regards, Diez -- http://mail.python.org/mailman/listinfo/python-list
