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What is the difference between NaN and None?
...13]: dtype('O')
In [14]: s_good.dtype
Out[14]: dtype('float64')
Jeff comm>me m>nts (below) on this:
np.nan allows for vectorized operations; its a float value, while None, by definition, forces object type, which basically disables all efficiency in numpy.
So repeat 3 tim>me m>s fast: objec...
Undo a Git m>me m>rge that hasn't been pushed yet
Within my master branch, I did a git m>me m>rge som>me m>-other-branch locally, but never pushed the changes to origin master. I didn't m>me m>an to m>me m>rge, so I'd like to undo it. When doing a git status after my m>me m>rge, I was getting this m>me m>ssage:
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virtualenv --no-site-packages and pip still finding global packages?
...te-packages would create a completely separate and isolated Python environm>me m>nt, but it doesn't seem to.
13 Answers
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Passing command line argum>me m>nts from Maven as properties in pom.xml
Is it possible to pass argum>me m>nts from command line to properties in pom.xml file ?
for example I run mvn ... argum>me m>nt
5 ...
Why use argparse rather than optparse?
I noticed that the Python 2.7 docum>me m>ntation includes yet another command-line parsing module. In addition to getopt and optparse we now have argparse .
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How to install Java SDK on CentOS?
...install java-1.7.0-openjdk-devel installs JDK.
– Thamm>me m> Gowda
Jan 9 '14 at 12:23
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SignalR: Why choose Hub vs. Persistent Connection?
...aying the lower-level persistent connections.
From the highly up-voted comm>me m>nt below:
Partially correct. You can get topics or groups in persistent connections as well. The big difference is dispatching different types of m>me m>ssages. For example you have different kinds of m>me m>ssages and you want ...
Writing a Python list of lists to a csv file
... "wb") as f:
writer = csv.writer(f)
writer.writerows(a)
This assum>me m>s your list is defined as a, as it is in your question. You can tweak the exact format of the output CSV via the various optional param>me m>ters to csv.writer() as docum>me m>nted in the library reference page linked above.
Update ...
Accessing last x characters of a string in Bash
...an access the first 3 characters of a string. Is there a equivalently easy m>me m>thod to access the last three characters?
4 A...
How to declare std::unique_ptr and what is the use of it?
... to understand how std::unique_ptr works and for that I found this docum>me m>nt. The author starts from the following example:
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