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Multiple levels of 'collection.defaultdict' in Python
...ng specific that you need help with? When d[new_key] is accessed, it will call the lambda which will create a new defaultdict(int). And when d[existing_key][new_key2] is accessed, a new int will be created.
– interjay
Oct 11 '13 at 12:53
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TypeError: module.__init__() takes at most 2 arguments (3 given)
...named Object.py . When I try to inherit from this class in another file, calling the constructor throws an exception:
5 An...
What is the difference between '/' and '//' when used for division?
...floating point division, and the latter is floor division, sometimes also called integer division.
In Python 2.2 or later in the 2.x line, there is no difference for integers unless you perform a from __future__ import division, which causes Python 2.x to adopt the 3.x behavior.
Regardless of the ...
Why is address zero used for the null pointer?
...non-protected-mode x86 CPU, for example, address 0 is the interrupt vector table.
– ChrisW
Aug 24 '15 at 13:53
@ChrisW...
Python argparse: How to insert newline in the help text?
...nfortunately Only the name of this class is considered a public API. All the methods provided by the class are considered an implementation detail. So probably not a great idea, although it might not matter, since 2.7 is meant to be the last 2.x python and you'll be expected to refactor lots ...
What's the difference between dist-packages and site-packages?
I'm a bit miffed by the python package installation process. Specifically, what's the difference between packages installed in the dist-packages directory and the site-packages directory?
...
Eclipse returns error message “Java was started but returned exit code = 1”
... message points to a problem with your Java version. Do you have a JDK installed?
Try adding the following (noting the new line):
/!\ make sure, that the -vm option occurs before the -vmargs command.
Everything after -vmargs is passed directly to the JVM.
-vm
c:/wherever/java/jdk1.6.0_21/...
How do you detect where two line segments intersect? [closed]
...f r × s = 0 and (q − p) × r ≠ 0, then the two lines are parallel and non-intersecting.
If r × s ≠ 0 and 0 ≤ t ≤ 1 and 0 ≤ u ≤ 1, the two line segments meet at the point p + t r = q + u s.
Otherwise, the two line segments are not parallel but do not intersect....
How can I force division to be floating point? Division keeps rounding down to 0?
... a floating point number in Python in the following?
c = a / b
What is really being asked here is:
"How do I force true division such that a / b will return a fraction?"
Upgrade to Python 3
In Python 3, to get true division, you simply do a / b.
>>> 1/2
0.5
Floor division, the classic di...
Hash function that produces short hashes?
...m that's strong against intentional modification, I've found an algorithm called adler32 that produces pretty short (~8 character) results. Choose it from the dropdown here to try it out:
http://www.sha1-online.com/
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