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Assigning a variable NaN in python without numpy
...e 1, in <module>
File "C:\Python35\lib\fractions.py", line 146, in __new__
numerator)
ValueError: Invalid literal for Fraction: 'nan'
>>>
>>> Fraction(float('nan'))
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "C:\Python35\...
Will the base class constructor be automatically called?
...ered Oct 31 '12 at 19:21
Science_FictionScience_Fiction
3,2131414 silver badges2424 bronze badges
...
Efficient way to apply multiple filters to pandas DataFrame or Series
...turn op(x[col],n)
In [15]: def f(x, *b):
return x[(np.logical_and(*b))]
In [16]: b1 = b(df, 'col1', ge, 1)
In [17]: b2 = b(df, 'col1', le, 1)
In [18]: f(df, b1, b2)
Out[18]:
col1 col2
1 1 11
Update: pandas 0.13 has a query method for these kind of use cases, assuming c...
How to do Base64 encoding in node.js?
...wered May 31 '11 at 2:46
onteria_onteria_
57.1k66 gold badges6363 silver badges6060 bronze badges
...
How is a CRC32 checksum calculated?
... 1100001010 = Quotient (nobody cares about the quotient)
_______________
10011 ) 11010110110000 = Augmented message (1101011011 + 0000)
=Poly 10011,,.,,....
-----,,.,,....
10011,.,,....
10011,.,,....
-----,.,,....
00001.,,....
...
Using Core Data, iCloud and CloudKit for syncing and backup and how it works together
I am in the early stages of creating an app where I would like to save, sync and backup data. The app will not store any files just data in a database. It is going to be iOS 8 and up so I am able to use CloudKit. I did some research and still not clear on how Core Data, iCloud and CloudKit work to...
How to create a self-signed certificate for a domain name for development?
I have subdomain.example.com that I use for development purposes. My web application solution contains a web API etc, that I need to call from external systems, hence I am not using localhost.
...
Python multiprocessing PicklingError: Can't pickle
...as mp
class Foo():
@staticmethod
def work(self):
pass
if __name__ == '__main__':
pool = mp.Pool()
foo = Foo()
pool.apply_async(foo.work)
pool.close()
pool.join()
yields an error almost identical to the one you posted:
Exception in thread Thread-2:
Tracebac...
How to check if the string is empty?
... the fact that empty sequences are false.
So you should use:
if not some_string:
or:
if some_string:
Just to clarify, sequences are evaluated to False or True in a Boolean context if they are empty or not. They are not equal to False or True.
...
Error: “The sandbox is not in sync with the Podfile.lock…” after installing RestKit with cocoapods
...ocoaPods/Specs.git' I also added this link in the pod file but same thing happened. please suggest.
– Mitesh Khatri
Oct 22 '14 at 6:09
...