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Is arr.__len__() the preferred way to get the length of an array in Python?
...ples:
my_tuple = (1,2,3,4,5)
len(my_tuple)
# 5
And strings, which are really just arrays of characters:
my_string = 'hello world'
len(my_string)
# 11
It was intentionally done this way so that lists, tuples and other container types or iterables didn't all need to explicitly implement a public...
How to list imported modules?
How to enumerate all imported modules?
9 Answers
9
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Extract traceback info from an exception object
...ion("foo occurred").with_traceback(tracebackobj)
These features are minimally described as part of the raise documentation.
All credit for this part of the answer should go to Vyctor, who first posted this information. I'm including it here only because this answer is stuck at the top, and Python...
Assigning a variable NaN in python without numpy
...aking) be said to be equal to one another -- see What is the rationale for all comparisons returning false for IEEE754 NaN values? for more details and information.
Instead, use math.isnan(...) if you need to determine if a value is NaN or not.
Furthermore, the exact semantics of the == operation...
Creating an abstract class in Objective-C
I'm originally a Java programmer who now works with Objective-C. I'd like to create an abstract class, but that doesn't appear to be possible in Objective-C. Is this possible?
...
“Private” (implementation) class in Python
I am coding a small Python module composed of two parts:
7 Answers
7
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Proper way to declare custom exceptions in modern Python?
...tionError(Exception):
def __init__(self, message, errors):
# Call the base class constructor with the parameters it needs
super(ValidationError, self).__init__(message)
# Now for your custom code...
self.errors = errors
That way you could pass dict of error me...
Traverse a list in reverse order in Python
... are reversed on the fly while traversing! This is an important feature of all these iteration functions (which all end on “ed”).
– Konrad Rudolph
Feb 9 '09 at 19:10
9
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PowerShell script to return versions of .NET Framework on a machine?
...t). It also outputs both Client and Full on 4.0 (if you have them both installed):
Get-ChildItem 'HKLM:\SOFTWARE\Microsoft\NET Framework Setup\NDP' -recurse |
Get-ItemProperty -name Version,Release -EA 0 |
Where { $_.PSChildName -match '^(?!S)\p{L}'} |
Select PSChildName, Version, Release
Based o...
Leaflet - How to find existing markers, and delete markers?
...
Should be a way to collect all of the layers used by Leaflet. :/
– jackyalcine
Aug 1 '12 at 21:39
10
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