A good way to make classes for more complex playing card types than those found in a standard deck? Question: I am extremely new to object-oriented programming, and am trying to begin learning in python by making a simple card game (as seems to be traditional!). I have done the following example which works fine, …
Setting default/empty attributes for user classes in __init__ Question: When I am creating a new class, should I set all instance attributes in __init__, even if they are None and in fact later assigned values in class methods? See example below for the attribute results of MyClass: class MyClass: def __init__(self,df): self.df = df self.results …
django – TypeError how to get instance of a foreignkey from the user instance Question: I am getting the following type error and its due to this instance in view. The model as you can see below where Employee is onetoone relation to User and Company is the foreignkey to the Employee. How would I …
Python : class definition with **kwargs Question: When trying to instantiate the following class I am getting the following error : “TypeError: __init__() takes exactly 2 arguments (3 given)” Do you know what would be the issue ? Here is the class definition : class db_create_table(): ”’ doc here ”’ def __init__(self,TableName, **kwargs ): self.TableName …
In Python, how can I inherit and override a method on a class instance, assigning this new version to the same name as the old one? Question: In Matplotlib, a common problem are unwanted white lines between Patch objects drawn with pcolor, pcolormesh, and contourf (see this question for the former two and this question …
Python Classes ( AttributeError: '' object has no attribute '') Question: Having trouble understanding the problem in my code, new to classes (generally python too, so sorry if I name things wrong). I receive this error: I think my code is too long winded to include in here, so I made a simplified version to …
Why won't dynamically adding a `__call__` method to an instance work? Question: In both Python 2 and Python 3 the code: class Foo(object): pass f = Foo() f.__call__ = lambda *args : args f(1, 2, 3) returns as error Foo object is not callable. Why does that happen? PS: With old-style classes it works as …
Why doesn't assigning to the loop variable modify the original list? How can I assign back to the list in a loop? Question: When I try this code: bar = [1,2,3] print(bar) for foo in bar: print(id(foo)) foo = 0 print(id(foo)) print(bar) I get this result: [1, 2, 3] 5169664 5169676 5169652 5169676 5169640 5169676 …
Create an anonymous class instance in python Question: Sometimes I need to create an anonymous class instance in python, just like c#: var o = new {attr1="something", attr2=344}; but in python I do it in this way: class Dummy: pass o = Dummy() o.attr1 = ‘something’ o.attr2 = 344 # EDIT 1 print o.attr1, o.attr2 …
How to keep track of class instances? Question: Toward the end of a program I’m looking to load a specific variable from all the instances of a class into a dictionary. For example: class Foo(): def __init__(self): self.x = {} foo1 = Foo() foo2 = Foo() … Let’s say the number of instances will vary …
