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How can I obtain the element-wise logical NOT of a pandas Series?
...n error, instead you'll get a garbage mask of ints that won't work as you expect.
In[1]: df = pd.DataFrame({'A':[True, False, np.nan], 'B':[True, False, True]})
In[2]: df.dropna(inplace=True)
In[3]: df['A']
Out[3]:
0 True
1 False
Name: A, dtype object
In[4]: ~df['A']
Out[4]:
0 -2
0 -1
Name...
If vs. Switch Speed
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The compiler can build jump tables where applicable. For example, when you use the reflector to look at the code produced, you will see that for huge switches on strings, the compiler will actually generate code that uses a hash table to dispatch these. The hash table uses the strin...
How to convert SSH keypairs generated using PuTTYgen (Windows) into key-pairs used by ssh-agent and
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puttygen supports exporting your private key to an OpenSSH compatible format. You can then use OpenSSH tools to recreate the public key.
Open PuttyGen
Click Load
Load your private key
Go to Conversions->Export OpenSSH and export your priv...
Missing return statement in a non-void method compiles
...nts after the while loop are unreachable (dead code) and would never be executed. But why doesn't the compiler even warn about returning something? Or why would a language allow us to have a non-void method having an infinite loop and not returning anything?
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Python AttributeError: 'module' object has no attribute 'Serial' [duplicate]
...rstand why it does work in some cases (for instance when you look at some examples in the serial website)
– VGO
Jul 9 '12 at 22:39
33
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What does the tilde (~) mean in my composer.json file?
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Tilde means next significant release. In your case, it is equivalent to >= 2.0, < 3.0.
The full explanation is at Tilde Version Range docs page:
The ~ operator is best explained by example: ~1.2 is equivalent to >=1.2 <2.0...
Algorithm to find Largest prime factor of a number
...1
return factors
pfs = prime_factors(1000)
largest_prime_factor = max(pfs) # The largest element in the prime factor list
The above method runs in O(n) in the worst case (when the input is a prime number).
EDIT:
Below is the O(sqrt(n)) version, as suggested in the comment. Here is the code...
if A vs if A is not None:
...the is None test was indeed the slowest for me. In pypy they all measured exactly the same :)
– John La Rooy
Mar 25 '13 at 6:09
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Downloading a picture via urllib and python
...ng urllib.request.urlretrieve (part of Python 3's legacy interface, works exactly the same)
import urllib.request
urllib.request.urlretrieve("http://www.gunnerkrigg.com//comics/00000001.jpg", "00000001.jpg")
share
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Unmount the directory which is mounted by sshfs in Mac [closed]
I've installed OSXFUSE in my mac and used sshfs to mount a remote directory. Now I would like to unmount it, but can't find the way.
My OS is OSX 10.8 Mountain.
Can anyone help?
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