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How to drop columns by name in a data frame
I have a large data set and I would like to read specific columns or drop all the others.
11 Answers
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ElasticSearch, Sphinx, Lucene, Solr, Xapian. Which fits for which usage? [closed]
...ethods rather than having a huge SQL query.
I saw elasticsearch recently and played with whoosh (a Python implementation of a search engine).
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How to undo “git commit --amend” done instead of “git commit”
...Note that HEAD@{1} is pointing somewhere different from the
# previous command. It's now pointing at the erroneously amended commit.)
git commit -C HEAD@{1}
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Using IQueryable with Linq
...ing data from a table in two ways, one which returns IEnumerable<T>, and one which returns an IQueryable<T>. Say, for example, you have a Products table, and you want to get all of the products whose cost is >$25.
If you do:
IEnumerable<Product> products = myORM.GetProducts(...
Remove secure warnings (_CRT_SECURE_NO_WARNINGS) from projects by default in Visual Studio
...ts in solution explorer.
Press Alt-F7 or right click in solution explorer and select "Properties"
Configurations:All Configurations
Click on the
Preprocessor Definitions line to invoke its editor
Choose
Edit...
Copy "_CRT_SECURE_NO_WARNINGS" into the Preprocessor Definitions white box on the ...
Scala list concatenation, ::: vs ++
Is there any difference between ::: and ++ for concatenating lists in Scala?
4 Answers
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Open file dialog and select a file using WPF controls and C#
I have a TextBox named textbox1 and a Button named button1 .
When I click on button1 I want to browse my files to search only for image files (type jpg, png, bmp...).
And when I select an image file and click Ok in the file dialog I want the file directory to be written in the textbox1.tex...
How do I use Node.js Crypto to create a HMAC-SHA1 hash?
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And to verify a hash, you should use crypto.timingSafeEqual(Buffer.from(a), Buffer.from(b)): stackoverflow.com/questions/31095905/…
– baptx
Aug 2 '19 at 15:19
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Flatten an irregular list of lists
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Using generator functions can make your example a little easier to read and probably boost the performance.
Python 2
def flatten(l):
for el in l:
if isinstance(el, collections.Iterable) and not isinstance(el, basestring):
for sub in flatten(el):
yield sub...
How do I convert between big-endian and little-endian values in C++?
How do I convert between big-endian and little-endian values in C++?
31 Answers
31
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