[Tutor] How to plot graph?
hi all, i'm new to python and this is advanced for me. is there a way to plot data with python? i want to plot EyVt, EyHt on the Y-axis and Lane on the X-axis as attached or below. currently i'm using Python2.5 and Win XP. thanks a lot. Eg: Platform: PC Tempt : 25 TAP0 :0 TAP1 :1 + Port Chnl Lane EyVt EyHt + 0 1 1 75 55 0 1 2 10 35 0 1 3 25 35 0 1 4 35 25 0 1 5 10 20 + Time: 20s Platform: PC Tempt : 25 TAP0:0 TAP1:1 + PortChnlLaneEyVtEyHt + 01 1 75 55 01 2 10 35 01 3 25 35 01 4 35 25 01 5 10 20 + Time: 20s___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Tutor Digest, Vol 83, Issue 74
): a = self.sujet.getValue() self.text.set(data_base[a][2]) if __name__ == '__main__': app=App() app.mainloop() # - end of file - # class AbstractObserver(object): Interface general des observateurs def __init__(self, sujet): Constructeur self.sujet = sujet def update(self): Methode a implementer par les observateurs pass On 01/18/2011 02:32 AM, Alan G wrote: Steven D'Apranosteveat pearwood.info writes: fact that multiple inheritance itself is often the wrong thing to use, and even when it is right, it is often tricky to get it right. To put it another way: don't use multiple inheritance unless you have to, there are better ways, such as by composition. Or use a language where MI is the normal and idiomatic way to do things because the language assumes it and so it just works. There are very few such languages but Lisp is one :-) Sadly Python isn't, and when using MI I always avoid super() Which is a huge shame since MI is where super() should be most useful... But in my experience MI in Python is definitely a place where explicit is better than implicit. Alan G. ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor -- Message: 4 Date: Tue, 18 Jan 2011 07:35:30 +0100 From: Izz ad-Din Ruhulessin izzaddin.ruhules...@gmail.com To: Hugo Arts hugo.yo...@gmail.com Cc: tutor@python.org Subject: Re: [Tutor] Exactly duplicating strftime behavior? Message-ID: AANLkTin-GdXd0rfupKHa=-RN+6d_ywYawDrv2Nsw=m...@mail.gmail.com Content-Type: text/plain; charset=iso-8859-1 Hi Hugo, Problem solved, thanks! Kind regards, Izz ad-Din 2011/1/17 Hugo Arts hugo.yo...@gmail.com On Mon, Jan 17, 2011 at 8:29 PM, Izz ad-Din Ruhulessin izzaddin.ruhules...@gmail.com wrote: Hi all, I'm designing a module which aims to provide full compatibility with Pythons' datetime module. However, I can't find out how some operators in strftime function, namely: those who use the locale. (%a, %A, %b, etc.) How do I access this locale and it's values? Thanks in advance. Kind regards, Izz ad-Din Check out the locale module: http://docs.python.org/library/locale.html#locale.nl_langinfo HTH, Hugo -- next part -- An HTML attachment was scrubbed... URL: http://mail.python.org/pipermail/tutor/attachments/20110118/522e990e/attachment-0001.html -- Message: 5 Date: Tue, 18 Jan 2011 10:30:53 + From: tee chwee liong tc...@hotmail.com To: tutor@python.org Subject: [Tutor] How to plot graph? Message-ID: bay156-w28c9e6f96071b97a33cdfeb5...@phx.gbl Content-Type: text/plain; charset=iso-8859-1 hi all, i'm new to python and this is advanced for me. is there a way to plot data with python? i want to plot EyVt, EyHt on the Y-axis and Lane on the X-axis as attached or below. currently i'm using Python2.5 and Win XP. thanks a lot. Eg: Platform: PC Tempt : 25 TAP0 :0 TAP1 :1 + Port Chnl Lane EyVt EyHt + 0 1 1 75 55 0 1 2 10 35 0 1 3 25 35 0 1 4 35 25 0 1 5 10 20 + Time: 20s -- next part -- An HTML attachment was scrubbed... URL: http://mail.python.org/pipermail/tutor/attachments/20110118/80b250af/attachment.html -- next part -- An embedded and charset-unspecified text was scrubbed... Name: sampledata.txt URL: http://mail.python.org/pipermail/tutor/attachments/20110118/80b250af/attachment.txt -- ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor End of Tutor Digest, Vol 83, Issue 74 * ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] How to plot graph?
On Tue, Jan 18, 2011 at 4:30 AM, tee chwee liong tc...@hotmail.com wrote: hi all, i'm new to python and this is advanced for me. is there a way to plot data with python? i want to plot EyVt, EyHt on the Y-axis and Lane on the X-axis as attached or below. currently i'm using Python2.5 and Win XP. thanks a lot. Take a look at the matplotlib library: http://matplotlib.sourceforge.net/ http://matplotlib.sourceforge.net/Especially the gallery page - there are several examples of what you can do. It may not be the easiest thing to start into as a beginner, but it's definitely available. If you're interested in doing a lot of scientific stuff, I'd also recommend using Python(X, Y): http://www.pythonxy.com/ as it bundles most of the tools you'll need (such as matplotlib) into one easy installer. Give it a try and if you get stuck, send us another email with what you've done, what you expect it to do, and what it actually does instead (including the full text of any and all tracebacks). HTH, Wayne ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Why super does not work !
By the way Tkinter does not support super() seems to be an 'old style'
class, this is perhaps the raison why MI does not work in this context:
*Python 2.7.1rc1 (r271rc1:86455, Nov 16 2010, 21:53:40)
[GCC 4.4.3] on linux2
Type help, copyright, credits or license for more information.
import Tkinter.Frame
Traceback (most recent call last):
File stdin, line 1, in module
ImportError: No module named Frame
from Tkinter import Frame
class App(Frame):
... def __init__(self):
... super(App, self).__init__()
...
a=App()
Traceback (most recent call last):
File stdin, line 1, in module
File stdin, line 3, in __init__
TypeError: must be type, not classobj
*
Steven, I corrected my code (even if I have a double Inheritance which
is ok in this context):
* class ListObservable(Listbox, Observable):
def __init__(self):
Observable.__init__(self)
self.listeContenu = StringVar()
self.listeContenu.set(' '.join(sorted(data_base.keys(
Listbox.__init__(self, listvariable=self.listeContenu,
selectmode='single')
self.grid(row=0, column=1, sticky=N+S+W)
self.bind('ListboxSelect', self.onSelect)
self._value = None
def onSelect(self, e):
if not self.curselection():
self.setValue(0)
else:
self.setValue(self.get(self.curselection()))
self.notify()
def setValue(self, select):
self._value = select
def getValue(self):
return self._value
class Entry1Observer(Entry, AbstractObserver):
def __init__(self, sujet=None):
AbstractObserver.__init__(self, sujet)
self.text = StringVar()
Entry.__init__(self, textvariable=self.text)
self.grid(row=2, column=2)
def update(self):
a = self.sujet.getValue()
self.text.set(data_base[a][0])*
I still need a advice about the possible improvement specially for
Entry observer object.
Regards
Karim
On 01/18/2011 07:31 AM, Karim wrote:
Thanks Izz, Luke, Steven and Alan!
That's I figured out with MI and super.
Steven I understand the point to have Listbox contains a Listbox.
Before the code was in App class and I extracted it to do an outside
class making the mistake.
But magic of Python it's working (but I know it's awful).
The code is working but I am not totally happy because of many
EntryObserver almost identical objects (except from update and grid()
options)
Is it possible to simplify this structure?
Regards
Karim
The rest of the code is below:
#!/usr/bin/env python2.7
Module ObserverGraphique.py
Une implementation du design pattern Observer.
from Tkinter import *
from observable import Observable
from observer import AbstractObserver
data_base = {
'Employe1': ['Joel', 'Durant', '0623'],
'Employe2': ['Marc', 'Donce', '0624'],
'Employe3': ['George', 'Roux','0625'],
'Employe4': ['Alain', 'Richard', '0626']
}
__all__ = ['App', 'ListObservable', 'Entry1Observer',
'Entry2Observer', 'Entry3Observer']
class App(Frame):
Application graphique avec Tkinter implementant un Observer
Design Pattern.
def __init__(self, master=None):
Frame.__init__(self, master)
self.master.title(Exemple : Observer Design Pattern)
self.grid()
self.createLabels()
self.createObservable()
self.createObservers()
self.registerObservers()
def createLabels(self):
Creation de widgets Label
self.label1 = Label(text=Nom :)
self.label2 = Label(text=Prenom :)
self.label3 = Label(text=Poste :)
self.label1.grid(row=1, column=1, sticky=W)
self.label2.grid(row=2, column=1, sticky=W)
self.label3.grid(row=3, column=1, sticky=W)
def createObservable(self):
Creation de la listBox observable.
self.sujet = ListObservable()
def createObservers(self):
Creation des champs d'entre texte observateurs de la liste.
self.nom= Entry1Observer(self.sujet)
self.prenom = Entry2Observer(self.sujet)
self.poste = Entry3Observer(self.sujet)
def registerObservers(self):
Enregistrement des observateurs.
self.sujet.attach(self.nom)
self.sujet.attach(self.prenom)
self.sujet.attach(self.poste)
class ListObservable(Listbox, Observable):
Creation de widget Listbox
def __init__(self):
#super(ListObservable, self).__init__()
Observable.__init__(self)
self._value = None
self.listeContenu = StringVar()
self.listeContenu.set(' '.join(sorted(data_base.keys(
self.liste = Listbox(listvariable=self.listeContenu,
selectmode='single')
self.liste.grid(row=0, column=1, sticky=N+S+W)
self.liste.bind('Double-1', self.onSelect)
self.liste.selection_set(0)
def onSelect(self, e):
if not self.liste.curselection():
self.setValue(0)
[Tutor] Convert an IP address from binary to decimal
Hi guys,
Please help me with this:
Convert an IP address from binary string to decimal format.There are
some preconditions:
1.IP address is in the form of '10010001100'.32 bits with no dot.
2.int(string, base) is not allowed, You have to implement the conversion .
3.Performance should be considered.
For example an IP address like ' '
would be converted to '255.255.255.255'
That's how I implement it. But I think it looks ugly and I wonder if
there is a better way to do this.
import re
import sys
def convert(bin_ip):
patt = re.compile(r'\d{8}')
bin_list = patt.findall(str(bin_ip))
dec_list = []
for bin in bin_list:
sum = 0
i = 7
for n in bin:
if int(n):
sum = sum + 2**i
i = i - 1
dec_list.append(str(sum))
dec_ip = '.'.join(dec_list)
print dec_ip
if __name__ == '__main__':
bin_ip = sys.argv[1:]
convert(bin_ip)
Thanks in advance and excuse my poor English.
Best regards,
Tom
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Re: [Tutor] Convert an IP address from binary to decimal
On 18/01/2011 14:45, Tom Lin wrote:
Hi guys,
Please help me with this:
Convert an IP address from binary string to decimal format.There are
some preconditions:
1.IP address is in the form of '10010001100'.32 bits with no dot.
2.int(string, base) is not allowed, You have to implement the conversion .
3.Performance should be considered.
For example an IP address like ' '
would be converted to '255.255.255.255'
That's how I implement it. But I think it looks ugly and I wonder if
there is a better way to do this.
import re
import sys
def convert(bin_ip):
patt = re.compile(r'\d{8}')
bin_list = patt.findall(str(bin_ip))
dec_list = []
for bin in bin_list:
sum = 0
i = 7
for n in bin:
if int(n):
sum = sum + 2**i
i = i - 1
dec_list.append(str(sum))
dec_ip = '.'.join(dec_list)
print dec_ip
if __name__ == '__main__':
bin_ip = sys.argv[1:]
convert(bin_ip)
Thanks in advance and excuse my poor English.
Best regards,
Tom
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If I knew the input to be perfect it would be a simple matter
'.'.join((str(int(input_ip[x:x+8], 2)) for x in range(4)))
--
Kind Regards,
Christian Witts
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Re: [Tutor] What is __weakref__ ?
Hello Steven, (1) slots = [] doesn't do anything special. You have misspelled __slots__. Yes sorry my mistake :-[ (2) Classes don't become read only just because you add __slots__ to them. All you prevent is adding extra attributes, and why would you wish to do that? I know this is ugly but until now it is the only way (with this side effect) I found to declare Enums class that I _understand_: *class CategoryType(object): Implements the enumeration and prevent associated newly created instances to redefine enums value via special class variable '__slots__' definition. It makes also, instances have no attributes at all. __slots__ = () TRANSISTOR, MOS, BIPOLAR, CAPACITOR, RESISTOR, DIODE, ESD, PAD, \ COMPARATOR, OPAMP, ADC, DAC, PLL, OTHER = range(14) def toString ( self, litteral ): Convert the litteral integer number to its associated string representation. if litteral == self.TRANSISTOR: return 'transistor' elif litteral == self.MOS: return 'mos' elif litteral == self.BIPOLAR:* [...] I discovered recently that I could configure __setattr__(self, name, value) by raising AttributeError to prevent to set up a new attribute value. Or use an conditional statement to avoid to define it twice. If you have good advice for enum (I hope I could understand) you welcome ;-) . Thus I use __slots__, __dict__ (in __setattr__) and I wanted to about much for __weakref__ Have you read the Fine Manual? http://docs.python.org/reference/datamodel.html#slots In fact, I already read that. But I am searching for doc about what is a weak reference. class K1(object): ... __slots__ = [] # Don't support weak-refs. ... class K2(object): ...__slots__ = '__weakref__' # Do support weak-refs. ... import weakref k1 = K1() k2 = K2() weakref.ref(k1) Traceback (most recent call last): File stdin, line 1, in module TypeError: cannot create weak reference to 'K1' object weakref.ref(k2) weakref at 0xb7c6661c; to 'K2' at 0xb7ee762c Same thing I don't know what to do with this object weakref :-[ as I don't know its meaning. That was my true question in fact; Regards ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] How to plot graph?
Thank you for seeking help. Next time please start a new thread rather than hijacking an existing one. -- Bob Gailer 919-636-4239 Chapel Hill NC ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Convert an IP address from binary to decimal
On 1/18/2011 8:08 AM, Christian Witts wrote:
On 18/01/2011 14:45, Tom Lin wrote:
Hi guys,
Please help me with this:
Convert an IP address from binary string to decimal format.There are
some preconditions:
1.IP address is in the form of '10010001100'.32 bits with no dot.
2.int(string, base) is not allowed, You have to implement the conversion .
Christian: note rule 2!
3.Performance should be considered.
For example an IP address like ' '
would be converted to '255.255.255.255'
That's how I implement it. But I think it looks ugly
Tom:
What exactly do you mean by ugly?
and I wonder if there is a better way to do this.
What do you mean by better?
The algorithm you programmed is one good way to accomplish your result.
The only problems I see are using re, ** and int() which are less
efficient than other ways.
The best might be - use slicing to get the 8 bit substrings, == to
test for 1 and bit shifting.
Start with 0, add1 if current bit == 1 and shift left.
Then try * 2 instead of shift left.
Run timing tests on the various approaches. Given that this is a very
fast algorithm timing tests might not be useful.
import re
import sys
def convert(bin_ip):
patt = re.compile(r'\d{8}')
bin_list = patt.findall(str(bin_ip))
dec_list = []
for bin in bin_list:
sum = 0
i = 7
for n in bin:
if int(n):
sum = sum + 2**i
i = i - 1
dec_list.append(str(sum))
dec_ip = '.'.join(dec_list)
print dec_ip
if __name__ == '__main__':
bin_ip = sys.argv[1:]
convert(bin_ip)
If I knew the input to be perfect it would be a simple matter
'.'.join((str(int(input_ip[x:x+8], 2)) for x in range(4)))
--
Bob Gailer
919-636-4239
Chapel Hill NC
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Re: [Tutor] Convert an IP address from binary to decimal
Tom Lin wrote:
Hi guys,
Please help me with this:
We don't do homework. We'll give you some hints but not do the work.
Convert an IP address from binary string to decimal format.There are
some preconditions:
1.IP address is in the form of '10010001100'.32 bits with no dot.
2.int(string, base) is not allowed, You have to implement the conversion .
3.Performance should be considered.
For example an IP address like ' '
would be converted to '255.255.255.255'
That's how I implement it. But I think it looks ugly and I wonder if
there is a better way to do this.
import re
import sys
def convert(bin_ip):
patt = re.compile(r'\d{8}')
bin_list = patt.findall(str(bin_ip))
The question does not say Search a string for zero or more IP addresses
in binary and convert them all. It says to convert an IP address
written in binary to dotted format. So throw away the regular
expression. It's wrong anyway: it would accept input like this:
1234
and try to convert that to an IP address.
Think about the problem you have. You are given as input a string of 32
0 or 1 characters. Anything else is an error -- there is no need to go
searching through a string looking for sequences of digits.
Once you have 32 characters, you can split it into four lots of eight
characters. How? Not with a regular expression!!! That is like using a
sledge-hammer to crack a peanut. Use slicing:
s = + x*24
s
''
s[0:8]
''
So you can take one 32-character string and slice it into four
8-character strings. Then *each* of the substrings can be converted from
binary into decimal. If you find a character other than 0 or 1, stop
immediately and raise an exception.
In pseudo-code:
Is the string exactly 32 characters? If not, then FAIL.
Split the string into four groups of eight.
For each group of eight, convert from binary to decimal. If you find
something other than 0 or 1, then FAIL.
Join the four groups with dots.
--
Steven
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Re: [Tutor] What is __weakref__ ?
On 1/18/2011 8:08 AM, Karim wrote:
I know this is ugly but until now it is the only way (with this side
effect) I found to declare Enums class that I _understand_:
*class CategoryType(object):
Implements the enumeration and prevent associated newly created
instances to redefine enums value via special class variable
'__slots__'
definition. It makes also, instances have no attributes at all.
__slots__ = ()
TRANSISTOR, MOS, BIPOLAR, CAPACITOR, RESISTOR, DIODE, ESD, PAD, \
COMPARATOR, OPAMP, ADC, DAC, PLL, OTHER = range(14)
def toString ( self, litteral ):
Convert the litteral integer number to its associated
string representation.
if litteral == self.TRANSISTOR:
return 'transistor'
elif litteral == self.MOS:
return 'mos'
elif litteral == self.BIPOLAR:*
[...]
IMHO this just cries out for a dictionary:
class CategoryType(object):
__slots__ = ()
enums = {
0: 'transistor',
1: 'mos',
...
}
def toString(self, literal):
Convert the literal integer number to its associated string
representation.
return self.enums[literal]
Note this does not handle invalid literal.
If you are happy with range 14) you could alternatively use a list:
enums = ['transistor, 'mos', ...]
--
Bob Gailer
919-636-4239
Chapel Hill NC
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Re: [Tutor] What is __weakref__ ?
Hello Bob,
Thanks for this better and simple approach!
To be perfect I would like to be able to do.
type = CategoryType()
type.TRANSISTOR
0
I will use your enums declaration and the range part to use as keys for
enums.
And I will raise a KeyError in toString() to handle invalid litteral.
Thanks!
Regards
Karim
On 01/18/2011 02:24 PM, bob gailer wrote:
On 1/18/2011 8:08 AM, Karim wrote:
I know this is ugly but until now it is the only way (with this side
effect) I found to declare Enums class that I _understand_:
*class CategoryType(object):
Implements the enumeration and prevent associated newly created
instances to redefine enums value via special class variable
'__slots__'
definition. It makes also, instances have no attributes at all.
__slots__ = ()
TRANSISTOR, MOS, BIPOLAR, CAPACITOR, RESISTOR, DIODE, ESD, PAD, \
COMPARATOR, OPAMP, ADC, DAC, PLL, OTHER = range(14)
def toString ( self, litteral ):
Convert the litteral integer number to its associated
string representation.
if litteral == self.TRANSISTOR:
return 'transistor'
elif litteral == self.MOS:
return 'mos'
elif litteral == self.BIPOLAR:*
[...]
IMHO this just cries out for a dictionary:
class CategoryType(object):
__slots__ = ()
enums = {
0: 'transistor',
1: 'mos',
...
}
def toString(self, literal):
Convert the literal integer number to its associated string
representation.
return self.enums[literal]
Note this does not handle invalid literal.
If you are happy with range 14) you could alternatively use a list:
enums = ['transistor, 'mos', ...]
--
Bob Gailer
919-636-4239
Chapel Hill NC
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Re: [Tutor] Convert an IP address from binary to decimal
于 2011-1-18 21:08, Christian Witts 写道:
On 18/01/2011 14:45, Tom Lin wrote:
Hi guys,
Please help me with this:
Convert an IP address from binary string to decimal format.There are
some preconditions:
1.IP address is in the form of '10010001100'.32 bits with no dot.
2.int(string, base) is not allowed, You have to implement the conversion .
3.Performance should be considered.
For example an IP address like ' '
would be converted to '255.255.255.255'
That's how I implement it. But I think it looks ugly and I wonder if
there is a better way to do this.
import re
import sys
def convert(bin_ip):
patt = re.compile(r'\d{8}')
bin_list = patt.findall(str(bin_ip))
dec_list = []
for bin in bin_list:
sum = 0
i = 7
for n in bin:
if int(n):
sum = sum + 2**i
i = i - 1
dec_list.append(str(sum))
dec_ip = '.'.join(dec_list)
print dec_ip
if __name__ == '__main__':
bin_ip = sys.argv[1:]
convert(bin_ip)
Thanks in advance and excuse my poor English.
Best regards,
Tom
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If I knew the input to be perfect it would be a simple matter
'.'.join((str(int(input_ip[x:x+8], 2)) for x in range(4)))
Thanks, Chris. Your code looks pretty simple. Awesome!
But one precondition is not to use int(string, base). How would you
implement the conversion?
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Re: [Tutor] Why super does not work !
Alan G wrote: Steven D'Aprano steve at pearwood.info writes: fact that multiple inheritance itself is often the wrong thing to use, and even when it is right, it is often tricky to get it right. To put it another way: don't use multiple inheritance unless you have to, there are better ways, such as by composition. Or use a language where MI is the normal and idiomatic way to do things because the language assumes it and so it just works. There are very few such languages but Lisp is one :-) I'm sorry, but I don't believe you :/ If it just works in Lisp, why does Lisp allow you to override the default linearization? I point you again at the series of articles by Michele Simionato in my previous post. The problems he points out with MI are mostly general to MI itself, and not to any one specific language implementation. Here's another one where he discusses implementing mixins without inheritance, and traits: http://www.artima.com/weblogs/viewpost.jsp?thread=246488 One problem with MI (another is that it encourages huge hierarchies that are impractical to use) is when you have diamond diagrams. This is unavoidable in languages where all objects have a common superclass, such as Python (new style classes only) and Lisp. http://en.wikipedia.org/wiki/Diamond_problem As you can see from the multiple designs chosen by different languages, there is no one right way to resolve the problem, but it's generally agreed that the least-worst (or most desirable, if you prefer) resolution is the so-called C3 linearization pioneered in Dylan and implemented by Python. The problem with Lisp's default linearization is that it is not monotomic. See this paper for details: http://192.220.96.201/dylan/linearization-oopsla96.html Converted to Python, if you have this class hierarchy: class Boat(object): pass class Dayboat(Boat): pass class Wheelboat(Boat): pass class Engineless(Dayboat): pass class SmallMultihull(Dayboat): pass class PedalWheelboat(Engineless, Wheelboat): pass class SmallCatamaran(SmallMultihull): pass class Pedalo(PedalWheelboat, SmallCatamaran): pass both Dylan and Python generate the optimal linearization: Pedalo, PedalWheelboat, Engineless, SmallCatamaran, SmallMultihull, Dayboat, Wheelboat, Boat, object while CLOS gives (or at least gave, at the time the paper was written) the surprising result that Wheelboat is promoted ahead of Dayboat: Pedalo, PedalWheelboat, Engineless, Wheelboat, SmallCatamaran, SmallMultihull, Dayboat, Boat, object Why is this surprising? Because Dayboat is more specific in the linearization of *both* of Pedalo's direct parents, and yet it is less specific in Pedalo itself. This is a bad thing. Both Lisp and Python/Dylan agree that there are potential class diagrams that are inconsistent. Here's an example from Python: class A(object): ... pass ... class B(object): ... pass ... class C(A, B): ... pass ... class D(B, A): ... pass ... class E(C, D): ... pass ... Traceback (most recent call last): File stdin, line 1, in module TypeError: Error when calling the metaclass bases Cannot create a consistent method resolution order (MRO) for bases B, A This gives you a clue as to part of the problem with MI: in general, multiple inheritance is inconsistent. It's only usable at all by imposing certain restrictions on it. Clearly there are no such impossible or inconsistent class diagrams if you limit yourself to single inheritance. MI is inherently more complicated. Sadly Python isn't, and when using MI I always avoid super() Diamonds were rare in old-style classes in Python, but when they occurred, Python's MI was potentially buggy. That is, there were combinations of class order that lead to real bugs (although other combinations did not). Unfortunately, *all* new-style classes form a diamond in MI. This is the problem that linearization solves for new-style classes, but only if you use super(). If you call the methods explicitly, you're doing it wrong, and it's only by chance (or by hard work, or by duplicating the logic of Python's MRO!) that your class hierarchy is not buggy. One problem with MI is that automatic method resolution does not play well with manual method resolution, and so mixing classes that use super() with classes that don't is a recipe for trouble. This is not a problem with MI, or with super, but with the classes that don't use super(). So if you're avoiding super(), you're classes are unsafe for others to inherit from using MI. In practice, unless you control the class and can take responsibility for it, or if it is documented as being MI friendly, you should never inherit from it except using single inheritance. -- Steven ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Convert an IP address from binary to decimal
Tom Lin wrote: But one precondition is not to use int(string, base). How would you implement the conversion? It's not hard. You have two choices: each character of the string represents a bit, and should be either a 0 or a 1 (anything else is an error). In which case its numeric value is either 0 or 1. if bit == '0': value = 0 elif bit == '1': value = 1 else: raise ValueError(not a binary IP address) If you are allowed to assume that the characters will only by 0 or 1, and that there will never be anything else, you can do something even smarter and faster. Here's a clue: total = 0 s = abaa for c in s: ... total += (c == a) ... total 3 The boolean flags True and False are actually disguised numbers with values 1 and 0. -- Steven ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] What is __weakref__ ?
On 1/18/2011 9:34 AM, Karim wrote: Hello Bob, Thanks for this better and simple approach! To be perfect I would like to be able to do. type = CategoryType() type.TRANSISTOR Add to the class: def __getattr__(self, name): return self.enums[name] Note this does not handle the upper/lower case issue. -- Bob Gailer 919-636-4239 Chapel Hill NC ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
[Tutor] OOP question
Hey guys, I'm trying to get a version of Roulette working and I had a quick question. Here is my code: class Outcome: def __init__(self, name, odds): self.name = name self.odds = odds def winAmount(self, amount): return odds*amount def __eq__(self, other): if (self == other): return True else: return False def __ne__(self, other): if (self != other): return True else: return False def __str__(self): return %s (%d:1) % ( self.name, self.odds ) Now whenever I try to call the winAmount method, I get the following error: NameError: global name 'odds' is not defined I'm wondering the following: I had thought that by initializing odds in the first initialization method that odds should then be accessible to all the other methods in the class. This does not seem to be the case. So what is the ideal fix? On the one hand I still need to initialize odds, right? But if odds is within the initialization method, how else can it be accessed by the other methods? Thanks so much! Ben ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] OOP question
Updated inline. Check the updated definiton of winAmount. Nick On Tue, Jan 18, 2011 at 9:25 AM, Ben Ganzfried ben.ganzfr...@gmail.comwrote: Hey guys, I'm trying to get a version of Roulette working and I had a quick question. Here is my code: class Outcome: def __init__(self, name, odds): self.name = name self.odds = odds def winAmount(self, amount): return self.odds*amount def __eq__(self, other): if (self == other): return True else: return False def __ne__(self, other): if (self != other): return True else: return False def __str__(self): return %s (%d:1) % ( self.name, self.odds ) Now whenever I try to call the winAmount method, I get the following error: NameError: global name 'odds' is not defined I'm wondering the following: I had thought that by initializing odds in the first initialization method that odds should then be accessible to all the other methods in the class. This does not seem to be the case. So what is the ideal fix? On the one hand I still need to initialize odds, right? But if odds is within the initialization method, how else can it be accessed by the other methods? Thanks so much! Ben ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] What is __weakref__ ?
On 01/18/2011 03:38 PM, bob gailer wrote: def __getattr__(self, name): return self.enums[name] Note this does not handle the upper/lower case issue. Thanks for the trick! works perfect! Regards Karim ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
[Tutor] Trying to import matplotlib : ImportError: No module named dateutil.rrule
Hello everyone, I am completely new in learning python and have a little background in programing. My problem occurs with the importation of matplotlib. I did download the module from http://sourceforge.net/projects/matplotlib/ . and I believe successfully install the corresping .egg file. a simple import matplotlib does not generate any errors. However, import matplotlib.pyplot or import pylab does generate the following error. Traceback (most recent call last): File stdin, line 1, in module File /Library/Frameworks/Python.framework/Versions/2.6/lib/ python2.6/site-packages/matplotlib.egg/pylab.py, line 1, in module from matplotlib.pylab import * File /Library/Frameworks/Python.framework/Versions/2.6/lib/ python2.6/site-packages/matplotlib.egg/matplotlib/pylab.py, line 220, in module from matplotlib import mpl # pulls in most modules File /Library/Frameworks/Python.framework/Versions/2.6/lib/ python2.6/site-packages/matplotlib.egg/matplotlib/mpl.py, line 3, in module from matplotlib import axes File /Library/Frameworks/Python.framework/Versions/2.6/lib/ python2.6/site-packages/matplotlib.egg/matplotlib/axes.py, line 19, in module import matplotlib.dates as mdates File /Library/Frameworks/Python.framework/Versions/2.6/lib/ python2.6/site-packages/matplotlib.egg/matplotlib/dates.py, line 119, in module from dateutil.rrule import rrule, MO, TU, WE, TH, FR, SA, SU, YEARLY, \ ImportError: No module named dateutil.rrule I would really appreciate if someone can help me out with this. As I said, I am pretty new and would need detailed explanation about how to solve the problem. I might need to let you know that I'm working on mac OS X version 10.5.8 Thanks by advance, Thierry ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Why super does not work !
On 01/17/2011 11:36 PM, Dave Angel wrote:
On 01/-10/-28163 02:59 PM, Karim wrote:
Hello,
I implemented Observer DP on a listbox (Tkinter) as follows and I don't
understand why super() is not working and Observable.__init__(self) is
working, cf below:
class ListObservable(Listbox, Observable):
Creation de widget Listbox
def __init__(self):
super(ListObservable, self).__init__()
#Observable.__init__(self)
self._value = None
self.listeContenu = StringVar()
self.listeContenu.set(' '.join(sorted(data_base.keys(
self.liste = Listbox(listvariable=self.listeContenu,
selectmode='single')
self.liste.grid(row=0, column=1, sticky=N+S+W)
self.liste.bind('Button-1', self.onSelect)
_The error is:_
Traceback (most recent call last):
File ./observerAppliGraphique.py, line 118, in module
app=App()
File ./observerAppliGraphique.py, line 37, in __init__
self.sujet.attach(self.nom)
File /home/karim/guiObserver/observable.py, line 11, in attach
self._observers.append(observer)
AttributeError: 'ListObservable' object has no attribute '_observers'
And the Observable class is:
class Observable(object):
Sujet a observer
def __init__(self):
self._observers = []
print('constructeur observable')
def attach(self, observer):
Attache un nouvel observateur
self._observers.append(observer)
def detach(self, observer):
Retire un nouvel observateur
self._observers.remove(observer)
def notify(self):
Avertit tous les observateurs que l'observable change d'etat
for observer in self._observers:
observer.update()
Just looking at what you supply, I'd suppose that ListBox doesn't
correctly call super() in its own __init__() method.
So I took a look at Tkinter.py, and sure enough, it just calls its own
direct parent, Widget.l
super() only works if all the classes you use are done consistently.
DaveA
Thanks for this precision!
Regards
Karim
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Re: [Tutor] OOP question
Ben Ganzfried wrote: Hey guys, I'm trying to get a version of Roulette working and I had a quick question. There's a quick answer and long answer. The quick answer is, you have to refer to self.odds, not just odds. The long answer is below: Here is my code: [...] Now whenever I try to call the winAmount method, I get the following error: NameError: global name 'odds' is not defined I'm wondering the following: I had thought that by initializing odds in the first initialization method that odds should then be accessible to all the other methods in the class. This does not seem to be the case. So what is the ideal fix? On the one hand I still need to initialize odds, right? But if odds is within the initialization method, how else can it be accessed by the other methods? The relevant method here is: def winAmount(self, amount): return odds*amount This tells Python: Look up the value for the name 'odds', and the name 'amount', multiply the two values, and return the result. How does Python look up names? It looks in *namespaces* -- first it looks in the function's local namespace (local variables like 'amount'), then it looks in the global namespace (global variables), and finally it looks in the builtin namespace (built-in functions like len, min, max, etc). You get a NameError, because there is no name 'odds' in any of those namespaces. To look for attributes, you have to look in the instance namespace: return self.odds*amount This looks up 'self' as above, and finds it as a local variable. Then it looks for an attribute 'odds' inside self, which is the result you want. This is much more general than just methods inside classes. The same process occurs whenever you use attribute access: import math math.sin(x) s = hello sailor s.upper() -- Steven ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
[Tutor] Problems passing a parameter in a GUI
Hi All, I hope this makes sense I am trying to write a GUI where you click on a button and each time you click on the button it shows in the entry text how many times you have clicked. However when I changed an earlier version of the code to pass a parameter it errors. This works :- from Tkinter import * class Application(Frame): GUI App def __init__(self, master): Initialize the frame. Frame.__init__(self, master) self.grid() self.create_widgets() def create_widgets(self): self.inst_lbl=Label(self, text=Click on the button to get instructions) self.inst_lbl.grid(row=0, column=0, columnspan=2, sticky=W) self.pw_lbl=Label(self, text=Password) self.submit_bttn=Button(self, text=Submit, command=self.reveal) self.submit_bttn.grid(row=1, column=1, columnspan=2, sticky=W) self.secret_text=Text(self, width=35, height=5, wrap=WORD) self.secret_text.grid(row=2, column=1, columnspan=2, sticky=W) self.helpinfo() def reveal(self): Calmexob = Calmex() results = Calmexob.getmess() self.secret_text.delete(0.0, END) self.secret_text.insert(0.0,results) def helpinfo(self): self.secret_text.insert(0.0,Start) class Calmex(object): def __init__(self): Default arg def getmess(self): mesg=Test return mesg #main root=Tk() root.title(Test) root.geometry(400x300) app=Application(root) root.mainloop() But when I changed it to use a number I get an error message. Here is the code from Tkinter import * class Application(Frame): GUI App def __init__(self, master): Initialize the frame. Frame.__init__(self, master) self.grid() x=0 self.create_widgets(x) def create_widgets(self,x): self.inst_lbl=Label(self, text=Click on the button to get instructions) self.inst_lbl.grid(row=0, column=0, columnspan=2, sticky=W) self.pw_lbl=Label(self, text=Password) x= self.submit_bttn=Button(self, text=Submit, command=self.reveal(x)) self.submit_bttn.grid(row=1, column=1, columnspan=2, sticky=W) self.secret_text=Text(self, width=35, height=5, wrap=WORD) self.secret_text.grid(row=2, column=1, columnspan=2, sticky=W) self.helpinfo() def reveal(self, x): Calmexob = Calmex(x) results = Calmexob.getmess(x) self.secret_text.delete(0.0, END) self.secret_text.insert(0.0,results) x=x+1 return x def helpinfo(self): self.secret_text.insert(0.0,Start) class Calmex(object): def __init__(self,x): Default arg def getmess(self,x): mesg=Test+str(x) return mesg #main root=Tk() root.title(Test) root.geometry(400x300) app=Application(root) root.mainloop() The error message is AttributeError: Application instance has no attribute 'secret_text' The only change is that I have declared x and changed the function reveal to take and pass x as an arguement. Thanks in advance. I hope this makes sense. ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Why super does not work !
Steven D'Aprano wrote: Alan G wrote: Or use a language where MI is the normal and idiomatic way to do things because the language assumes it and so it just works. There are very few such languages but Lisp is one :-) I'm sorry, but I don't believe you :/ That's a bit harsh... Let me rephrase that as I'm sorry, I find that hard to believe. -- Steven ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] What is __weakref__ ?
Karim wrote: Same thing I don't know what to do with this object weakref :-[ as I don't know its meaning. That was my true question in fact; http://mindtrove.info/python-weak-references/ http://www.doughellmann.com/PyMOTW-ja/weakref/index.html -- Steven ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Problems passing a parameter in a GUI
You have other issues at play here, but to answer your question from below: You are calling the method reveal prior to creating the global object secret_text You can try moving: x= self.submit_bttn=Button(self, text=Submit, command=self.reveal(x)) below self.secret_text = You will also find that you have not defined something called self.submit_bttn and there are more errors beyond that, but that's past the scope of your question. On Tue, Jan 18, 2011 at 4:36 PM, David Holland davholla2...@yahoo.co.ukwrote: Hi All, I hope this makes sense I am trying to write a GUI where you click on a button and each time you click on the button it shows in the entry text how many times you have clicked. However when I changed an earlier version of the code to pass a parameter it errors. This works :- from Tkinter import * class Application(Frame): GUI App def __init__(self, master): Initialize the frame. Frame.__init__(self, master) self.grid() self.create_widgets() def create_widgets(self): self.inst_lbl=Label(self, text=Click on the button to get instructions) self.inst_lbl.grid(row=0, column=0, columnspan=2, sticky=W) self.pw_lbl=Label(self, text=Password) self.submit_bttn=Button(self, text=Submit, command=self.reveal) self.submit_bttn.grid(row=1, column=1, columnspan=2, sticky=W) self.secret_text=Text(self, width=35, height=5, wrap=WORD) self.secret_text.grid(row=2, column=1, columnspan=2, sticky=W) self.helpinfo() def reveal(self): Calmexob = Calmex() results = Calmexob.getmess() self.secret_text.delete(0.0, END) self.secret_text.insert(0.0,results) def helpinfo(self): self.secret_text.insert(0.0,Start) class Calmex(object): def __init__(self): Default arg def getmess(self): mesg=Test return mesg #main root=Tk() root.title(Test) root.geometry(400x300) app=Application(root) root.mainloop() But when I changed it to use a number I get an error message. Here is the code from Tkinter import * class Application(Frame): GUI App def __init__(self, master): Initialize the frame. Frame.__init__(self, master) self.grid() x=0 self.create_widgets(x) def create_widgets(self,x): self.inst_lbl=Label(self, text=Click on the button to get instructions) self.inst_lbl.grid(row=0, column=0, columnspan=2, sticky=W) self.pw_lbl=Label(self, text=Password) x= self.submit_bttn=Button(self, text=Submit, command=self.reveal(x)) self.submit_bttn.grid(row=1, column=1, columnspan=2, sticky=W) self.secret_text=Text(self, width=35, height=5, wrap=WORD) self.secret_text.grid(row=2, column=1, columnspan=2, sticky=W) self.helpinfo() def reveal(self, x): Calmexob = Calmex(x) results = Calmexob.getmess(x) self.secret_text.delete(0.0, END) self.secret_text.insert(0.0,results) x=x+1 return x def helpinfo(self): self.secret_text.insert(0.0,Start) class Calmex(object): def __init__(self,x): Default arg def getmess(self,x): mesg=Test+str(x) return mesg #main root=Tk() root.title(Test) root.geometry(400x300) app=Application(root) root.mainloop() The error message is AttributeError: Application instance has no attribute 'secret_text' The only change is that I have declared x and changed the function reveal to take and pass x as an arguement. Thanks in advance. I hope this makes sense. ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Problems passing a parameter in a GUI
I took another look at what you are trying to do, and if I wanted to count the number of times the button was pressed in the same way you are trying I would do something like this instead: from Tkinter import * class Application(Frame): GUI App def __init__(self, master): Initialize the frame. Frame.__init__(self, master) self.grid() self.create_widgets() self.c = Counter() def create_widgets(self): self.inst_lbl=Label(self, text=Click on the button to get instructions) self.inst_lbl.grid(row=0, column=0, columnspan=2, sticky=W) self.pw_lbl=Label(self, text=Password) self.submit_bttn=Button(self, text=Submit, command=self.reveal) self.submit_bttn.grid(row=1, column=1, columnspan=2, sticky=W) self.secret_text=Text(self, width=35, height=5, wrap=WORD) self.secret_text.grid(row=2, column=1, columnspan=2, sticky=W) self.helpinfo() def reveal(self): self.c.a +=1 Calmexob = Calmex(self.c.a) results = Calmexob.getmess() self.secret_text.delete(0.0, END) self.secret_text.insert(0.0,results) def helpinfo(self): self.secret_text.insert(0.0,Start) class Counter: a = 0 class Calmex(object): def __init__(self,a): Default arg self.a = a def getmess(self): mesg=Test + str(self.a) return mesg #main root=Tk() root.title(Test) root.geometry(400x300) app=Application(root) root.mainloop() I haven't looked at the whole program, just what you have already done. Really, all you want to do is keep track of how many times reveal gets called, or at least I think that is what you are trying to do, so just add a simple counter, which I chose to use an object to do. I then passed the attribute holding this value to instantiate your Calmex instance and once getmess gets called it should do the right thing. This might not be what you are after though, at the end of the day. On Tue, Jan 18, 2011 at 5:02 PM, James Reynolds eire1...@gmail.com wrote: You have other issues at play here, but to answer your question from below: You are calling the method reveal prior to creating the global object secret_text You can try moving: x= self.submit_bttn=Button(self, text=Submit, command=self.reveal(x)) below self.secret_text = You will also find that you have not defined something called self.submit_bttn and there are more errors beyond that, but that's past the scope of your question. On Tue, Jan 18, 2011 at 4:36 PM, David Holland davholla2...@yahoo.co.ukwrote: Hi All, I hope this makes sense I am trying to write a GUI where you click on a button and each time you click on the button it shows in the entry text how many times you have clicked. However when I changed an earlier version of the code to pass a parameter it errors. This works :- from Tkinter import * class Application(Frame): GUI App def __init__(self, master): Initialize the frame. Frame.__init__(self, master) self.grid() self.create_widgets() def create_widgets(self): self.inst_lbl=Label(self, text=Click on the button to get instructions) self.inst_lbl.grid(row=0, column=0, columnspan=2, sticky=W) self.pw_lbl=Label(self, text=Password) self.submit_bttn=Button(self, text=Submit, command=self.reveal) self.submit_bttn.grid(row=1, column=1, columnspan=2, sticky=W) self.secret_text=Text(self, width=35, height=5, wrap=WORD) self.secret_text.grid(row=2, column=1, columnspan=2, sticky=W) self.helpinfo() def reveal(self): Calmexob = Calmex() results = Calmexob.getmess() self.secret_text.delete(0.0, END) self.secret_text.insert(0.0,results) def helpinfo(self): self.secret_text.insert(0.0,Start) class Calmex(object): def __init__(self): Default arg def getmess(self): mesg=Test return mesg #main root=Tk() root.title(Test) root.geometry(400x300) app=Application(root) root.mainloop() But when I changed it to use a number I get an error message. Here is the code from Tkinter import * class Application(Frame): GUI App def __init__(self, master): Initialize the frame. Frame.__init__(self, master) self.grid() x=0 self.create_widgets(x) def create_widgets(self,x): self.inst_lbl=Label(self, text=Click on the button to get instructions) self.inst_lbl.grid(row=0, column=0, columnspan=2, sticky=W) self.pw_lbl=Label(self, text=Password) x= self.submit_bttn=Button(self, text=Submit, command=self.reveal(x)) self.submit_bttn.grid(row=1, column=1, columnspan=2, sticky=W) self.secret_text=Text(self, width=35, height=5, wrap=WORD)
Re: [Tutor] Problems passing a parameter in a GUI
On 01/-10/-28163 02:59 PM, David Holland wrote: Hi All, I hope this makes sense I am trying to write a GUI where you click on a button and each time you click on the button it shows in the entry text how many times you have clicked. However when I changed an earlier version of the code to pass a parameter it errors. This works :- from Tkinter import * class Application(Frame): GUI App def __init__(self, master): Initialize the frame. Frame.__init__(self, master) self.grid() self.create_widgets() def create_widgets(self): self.inst_lbl=Label(self, text=Click on the button to get instructions) self.inst_lbl.grid(row=0, column=0, columnspan=2, sticky=W) self.pw_lbl=Label(self, text=Password) self.submit_bttn=Button(self, text=Submit, command=self.reveal) self.submit_bttn.grid(row=1, column=1, columnspan=2, sticky=W) self.secret_text=Text(self, width=35, height=5, wrap=WORD) self.secret_text.grid(row=2, column=1, columnspan=2, sticky=W) self.helpinfo() def reveal(self): Calmexob = Calmex() results = Calmexob.getmess() self.secret_text.delete(0.0, END) self.secret_text.insert(0.0,results) def helpinfo(self): self.secret_text.insert(0.0,Start) class Calmex(object): def __init__(self): Default arg def getmess(self): mesg=Test return mesg #main root=Tk() root.title(Test) root.geometry(400x300) app=Application(root) root.mainloop() But when I changed it to use a number I get an error message. Here is the code from Tkinter import * class Application(Frame): GUI App def __init__(self, master): Initialize the frame. Frame.__init__(self, master) self.grid() x=0 self.create_widgets(x) def create_widgets(self,x): self.inst_lbl=Label(self, text=Click on the button to get instructions) self.inst_lbl.grid(row=0, column=0, columnspan=2, sticky=W) self.pw_lbl=Label(self, text=Password) x= self.submit_bttn=Button(self, text=Submit, command=self.reveal(x)) self.submit_bttn.grid(row=1, column=1, columnspan=2, sticky=W) self.secret_text=Text(self, width=35, height=5, wrap=WORD) self.secret_text.grid(row=2, column=1, columnspan=2, sticky=W) self.helpinfo() def reveal(self, x): Calmexob = Calmex(x) results = Calmexob.getmess(x) self.secret_text.delete(0.0, END) self.secret_text.insert(0.0,results) x=x+1 return x def helpinfo(self): self.secret_text.insert(0.0,Start) class Calmex(object): def __init__(self,x): Default arg def getmess(self,x): mesg=Test+str(x) return mesg #main root=Tk() root.title(Test) root.geometry(400x300) app=Application(root) root.mainloop() The error message is AttributeError: Application instance has no attribute 'secret_text' The only change is that I have declared x and changed the function reveal to take and pass x as an arguement. Thanks in advance. I hope this makes sense. I don't have time to try to understand all the tk stuff. And it sure would have been nice if you showed the whole error message, including the traceback. You didn't even tell us what line it was on. But your problem is that you have an instance of Application without the secret_text attribute, but you're trying to use it. You should get in the habit of initializing all attributes in __init__(). Anyway, it looks like the only places that could get the error are inside the methods reveal() and selfinfo(). If either gets called before create_widget() finishes, you could get this error. The stack trace would show just what combination of method calls is making this happen. DaveA ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] What is __weakref__ ?
Thanks for the links Steven! Regards Karim On 01/18/2011 10:49 PM, Steven D'Aprano wrote: Karim wrote: Same thing I don't know what to do with this object weakref :-[ as I don't know its meaning. That was my true question in fact; http://mindtrove.info/python-weak-references/ http://www.doughellmann.com/PyMOTW-ja/weakref/index.html ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
