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Checking if array is multidimensional or not?
...will recursively count the array. This is particularly useful for counting all the elements of a multidimensional array. count() does not detect infinite recursion.
However this method does not detect array(array()).
share...
Python multiprocessing PicklingError: Can't pickle
...the one you posted:
Exception in thread Thread-2:
Traceback (most recent call last):
File "/usr/lib/python2.7/threading.py", line 552, in __bootstrap_inner
self.run()
File "/usr/lib/python2.7/threading.py", line 505, in run
self.__target(*self.__args, **self.__kwargs)
File "/usr/lib/p...
Do zombies exist … in .NET?
I was having a discussion with a teammate about locking in .NET. He's a really bright guy with an extensive background in both lower-level and higher-level programming, but his experience with lower level programming far exceeds mine. Anyway, He argued that .NET locking should be avoided on critic...
What is 'Pattern Matching' in functional languages?
...wesome.
Algebraic data types in a nutshell
ML-like functional languages allow you define simple data types called "disjoint unions" or "algebraic data types". These data structures are simple containers, and can be recursively defined. For example:
type 'a list =
| Nil
| Cons of 'a * 'a ...
How to print a groupby object
...like a bug to me. I created an issue.
But a groupby operation doesn't actually return a DataFrame sorted by group. The .head() method is a little misleading here -- it's just a convenience feature to let you re-examine the object (in this case, df) that you grouped. The result of groupby is separat...
Why return NotImplemented instead of raising NotImplementedError
...
It's because __lt__() and related comparison methods are quite commonly used indirectly in list sorts and such. Sometimes the algorithm will choose to try another way or pick a default winner. Raising an exception would break out of the s...
Python circular importing?
... of it) for the first time, the code inside the module is executed sequentially like any other code; e.g., it is not treated any differently that the body of a function. An import is just a command like any other (assignment, a function call, def, class). Assuming your imports occur at the top of th...
How to empty a list?
...
This actually removes the contents from the list, but doesn't replace the old label with a new empty list:
del lst[:]
Here's an example:
lst1 = [1, 2, 3]
lst2 = lst1
del lst1[:]
print(lst2)
For the sake of completeness, the slic...
Handling a colon in an element ID in a CSS selector [duplicate]
...mpatibility mode. This other answer to this same question did work. basically \3A instead of \:.
– Merlyn Morgan-Graham
Mar 30 '12 at 2:32
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Iterate two Lists or Arrays with one ForEach statement in C#
... Did not know anything about those Zip operations, I'll make a small research on that topic. Thanks!
– Hugo
Dec 23 '09 at 23:02
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