«

On Feb 12, 7:21*pm, Andrea Crotti <andrea.crott...@gmail.com> wrote:
> Il giorno 12/feb/2011, alle ore 00.45, Martin De Kauwe ha scritto:
>
> > Hi,
>
> > yes I read a .INI file using ConfigParser, just similar sections (in
> > my opinion) to make one object which i can then pass to different
> > classes. E.G.
>
> Ok then I suggest configobj, less buggy and much more powerful than ConfigParser:http://www.voidspace.org.uk/python/configobj.html
>
> (and included from python 2.7).
> In this way you can also simply just carry around that dictionary, and it will be correctly
> typed if you validate the input.

That is interesting however I am using python 2.6 so I guess I shall
have to stick as I am for the moment. I think the way I used it above
was quite straight forward? It seemed OK? What are the issues?

On Feb 12, 8:06*pm, Martin De Kauwe <mdeka...@gmail.com> wrote:
> On Feb 12, 7:21*pm, Andrea Crotti <andrea.crott...@gmail.com> wrote:
>
> > Il giorno 12/feb/2011, alle ore 00.45, Martin De Kauwe ha scritto:
>
> > > Hi,
>
> > > yes I read a .INI file using ConfigParser, just similar sections (in
> > > my opinion) to make one object which i can then pass to different
> > > classes. E.G.
>
> > Ok then I suggest configobj, less buggy and much more powerful than ConfigParser:http://www.voidspace.org.uk/python/configobj.html
>
> > (and included from python 2.7).
> > In this way you can also simply just carry around that dictionary, and it will be correctly
> > typed if you validate the input.
>
> That is interesting however I am using python 2.6 so I guess I shall
> have to stick as I am for the moment. I think the way I used it above
> was quite straight forward? It seemed OK? What are the issues?

Ignore that I have just tested it (it works in 2.6), much better!
Thanks!!

On 2/12/2011 1:24 AM, Martin De Kauwe wrote:

> The point of this posting was just to ask those that know, whether it
> was a bad idea to use the class object in the way I had or was that
> OK? And if I should have just used a dictionary, why?

Did you miss my suggestion to use a module rather than a class?
Modules do not have some of the disadvantages of classes listed by J. Nagle.

--
Terry Jan Reedy

On Feb 13, 5:12*am, Terry Reedy <tjre...@udel.edu> wrote:
> On 2/12/2011 1:24 AM, Martin De Kauwe wrote:
>
> > The point of this posting was just to ask those that know, whether it
> > was a bad idea to use the class object in the way I had or was that
> > OK? And if I should have just used a dictionary, why?
>
> Did you miss my suggestion to use a module rather than a class?
> Modules do not have some of the disadvantages of classes listed by J. Nagle.
>
> --
> Terry Jan Reedy

Hi, sorry I did. I just re-read it, could you provide an example?
Sorry i am having a major mind blank this morning (I think this is
obvious!?). And it would meet all of the criteria outlined by John
Nagle?

On Fri, Feb 11, 2011 at 10:20 PM, Steven D'Aprano
<steve+> wrote:
> On Fri, 11 Feb 2011 21:47:32 -0800, Dan Stromberg wrote:
>
>> Did you have some sort of bad experience with pylint? *Do you resent the
>> 20 minutes it takes to set it up?
>
> If you read my post more carefully and less defensively, you'll see that
> nothing I said was *opposed* to the use of pylint, merely that pylint is
> not a substitute of a good, thorough test suite.

Actually, I mentioned the value of pylint. Then you asked me if my
unit tests were broken.

What would you infer from such a question?

On 2/12/2011 9:20 PM, Martin De Kauwe wrote:
> On Feb 13, 5:12 am, Terry Reedy<tjre...@udel.edu> wrote:
>> On 2/12/2011 1:24 AM, Martin De Kauwe wrote:
>>
>>> The point of this posting was just to ask those that know, whether it
>>> was a bad idea to use the class object in the way I had or was that
>>> OK? And if I should have just used a dictionary, why?
>>
>> Did you miss my suggestion to use a module rather than a class?
>> Modules do not have some of the disadvantages of classes listed by J. Nagle.
>>
>> --
>> Terry Jan Reedy
>
> Hi, sorry I did. I just re-read it, could you provide an example?

I am not sure what you are asking. tkinter.contants is one example.

> Sorry i am having a major mind blank this morning (I think this is
> obvious!?). And it would meet all of the criteria outlined by John
> Nagle?

A module will work fine if but only if you commit yourself to having all
keys be legal Python identifiers. But that is usually not a problem with
configuration values.


--
Terry Jan Reedy

On Sat, 12 Feb 2011 19:45:55 -0800, Dan Stromberg wrote:

> On Fri, Feb 11, 2011 at 10:20 PM, Steven D'Aprano
> <steve+> wrote:
>> On Fri, 11 Feb 2011 21:47:32 -0800, Dan Stromberg wrote:
>>
>>> Did you have some sort of bad experience with pylint? Â*Do you resent
>>> the 20 minutes it takes to set it up?
>>
>> If you read my post more carefully and less defensively, you'll see
>> that nothing I said was *opposed* to the use of pylint, merely that
>> pylint is not a substitute of a good, thorough test suite.
>
> Actually, I mentioned the value of pylint. Then you asked me if my unit
> tests were broken.
>
> What would you infer from such a question?


That I believed that you are using pylint as a substitute for unit tests,
instead of in conjunction with unit tests.



--
Steven

On Feb 13, 6:35*pm, Terry Reedy <tjre...@udel.edu> wrote:
> On 2/12/2011 9:20 PM, Martin De Kauwe wrote:
>
> > On Feb 13, 5:12 am, Terry Reedy<tjre...@udel.edu> *wrote:
> >> On 2/12/2011 1:24 AM, Martin De Kauwe wrote:
>
> >>> The point of this posting was just to ask those that know, whether it
> >>> was a bad idea to use the class object in the way I had or was that
> >>> OK? And if I should have just used a dictionary, why?
>
> >> Did you miss my suggestion to use a module rather than a class?
> >> Modules do not have some of the disadvantages of classes listed by J. Nagle.
>
> >> --
> >> Terry Jan Reedy
>
> > Hi, sorry I did. I just re-read it, could you provide an example?
>
> I am not sure what you are asking. tkinter.contants is one example.
>
> > Sorry i am having a major mind blank this morning (I think this is
> > obvious!?). And it would meet all of the criteria outlined by John
> > Nagle?
>
> A module will work fine if but only if you commit yourself to having all
> keys be legal Python identifiers. But that is usually not a problem with
> configuration values.
>
> --
> Terry Jan Reedy

I think I got it, did you mean something like this?


class Constants:

radius_of_earth = 6.37122E+6
days_as_yrs = 1.0 / 365.25
m2_as_ha = 1E-4 # metres squared as hectares
g_as_tonnes = 1E-6 # grammes as tonnes
kg_as_tonnes = 1E-3 # kg as tonnes
kg_as_g = 1E+3

def __init__(self):

self.radius_of_earth = self.__class__.radius_of_earth
self.days_as_yrs = self.__class__.days_as_yrs
self.m2_as_ha = self.__class__.m2_as_ha
self.g_as_tonnes = self.__class__.g_as_tonnes
self.kg_as_tonnes = self.__class__.kg_as_tonnes
self.kg_as_g = self.__class__.kg_as_g


usage something like

>>>from constants import Constants
>>>Constants.kg_as_g
>>>1000.0

Something similar for the params?

thanks

On Feb 14, 10:16*am, Martin De Kauwe <mdeka...@gmail.com> wrote:
> On Feb 13, 6:35*pm, Terry Reedy <tjre...@udel.edu> wrote:
>
>
>
>
>
> > On 2/12/2011 9:20 PM, Martin De Kauwe wrote:
>
> > > On Feb 13, 5:12 am, Terry Reedy<tjre...@udel.edu> *wrote:
> > >> On 2/12/2011 1:24 AM, Martin De Kauwe wrote:
>
> > >>> The point of this posting was just to ask those that know, whether it
> > >>> was a bad idea to use the class object in the way I had or was that
> > >>> OK? And if I should have just used a dictionary, why?
>
> > >> Did you miss my suggestion to use a module rather than a class?
> > >> Modules do not have some of the disadvantages of classes listed by J.. Nagle.
>
> > >> --
> > >> Terry Jan Reedy
>
> > > Hi, sorry I did. I just re-read it, could you provide an example?
>
> > I am not sure what you are asking. tkinter.contants is one example.
>
> > > Sorry i am having a major mind blank this morning (I think this is
> > > obvious!?). And it would meet all of the criteria outlined by John
> > > Nagle?
>
> > A module will work fine if but only if you commit yourself to having all
> > keys be legal Python identifiers. But that is usually not a problem with
> > configuration values.
>
> > --
> > Terry Jan Reedy
>
> I think I got it, did you mean something like this?
>
> class Constants:
>
> * * radius_of_earth = 6.37122E+6
> * * days_as_yrs = 1.0 / 365.25
> * * m2_as_ha = 1E-4 *# metres squared as hectares
> * * g_as_tonnes = 1E-6 *# grammes as tonnes
> * * kg_as_tonnes = 1E-3 *# kg as tonnes
> * * kg_as_g = 1E+3
>
> * * def __init__(self):
>
> * * * * self.radius_of_earth = self.__class__.radius_of_earth
> * * * * self.days_as_yrs = self.__class__.days_as_yrs
> * * * * self.m2_as_ha = self.__class__.m2_as_ha
> * * * * self.g_as_tonnes = self.__class__.g_as_tonnes
> * * * * self.kg_as_tonnes = self.__class__.kg_as_tonnes
> * * * * self.kg_as_g = self.__class__.kg_as_g
>
> usage something like
>
> >>>from constants import Constants
> >>>Constants.kg_as_g
> >>>1000.0
>
> Something similar for the params?
>
> thanks

And then I guess define some default parameters and then use configobj
to parse a .INI file. Then adjust those parameters change in the .INI
file?

e.g.

from parameters import DefaultParameters as params
# d -> comes from .INI file
p = params()
for key, value in d.iteritems():
# change anything read from file
p.__dict__[key] = value

?

On 2/13/2011 6:16 PM, Martin De Kauwe wrote:

> I think I got it, did you mean something like this?
>
>
> class Constants:
>
> radius_of_earth = 6.37122E+6
> days_as_yrs = 1.0 / 365.25
> m2_as_ha = 1E-4 # metres squared as hectares
> g_as_tonnes = 1E-6 # grammes as tonnes
> kg_as_tonnes = 1E-3 # kg as tonnes
> kg_as_g = 1E+3
>
> def __init__(self):
>
> self.radius_of_earth = self.__class__.radius_of_earth
> self.days_as_yrs = self.__class__.days_as_yrs
> self.m2_as_ha = self.__class__.m2_as_ha
> self.g_as_tonnes = self.__class__.g_as_tonnes
> self.kg_as_tonnes = self.__class__.kg_as_tonnes
> self.kg_as_g = self.__class__.kg_as_g
>
>
> usage something like
>
>>> >from constants import Constants
>>>> Constants.kg_as_g
>>>> 1000.0

No, simpler. No class statememt necessarily needed.

module constants
----------------

radius_of_earth = 6.37122E+6
days_as_yrs = 1.0 / 365.25
m2_as_ha = 1E-4 # metres squared as hectares
g_as_tonnes = 1E-6 # grammes as tonnes
kg_as_tonnes = 1E-3 # kg as tonnes
kg_as_g = 1E+3
# could also have code to load stuff from other files


usage
=====
>>> import constants
>>> constants.kg_as_g
1000.0

Real example
>>> import math
>>> math.pi, math.e
(3.141592653589793, 2.718281828459045)


--
Terry Jan Reedy