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Combine two columns of text in pandas dataframe
...tenate them directly:
df["period"] = df["Year"] + df["quarter"]
If one (or both) of the columns are not string typed, you should convert it (them) first,
df["period"] = df["Year"].astype(str) + df["quarter"]
Beware of NaNs when doing this!
If you need to join multiple string columns, you ca...
Naming convention for utility classes in Java
...
Like many such conventions, what's important is not so much what convention you use, as that you use it consistently. Like, if you have three utility classes and you call them CustomerUtil, ProductUtils, and StoreUtility, other people trying to use your classes a...
Send string to stdin
... above is the same as
cat <<EOF
This is coming from the stdin
EOF
or you can redirect output from a command, like
diff <(ls /bin) <(ls /usr/bin)
or you can read as
while read line
do
echo =$line=
done < some_file
or simply
echo something | read param
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Difference between `constexpr` and `const`
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Basic meaning and syntax
Both keywords can be used in the declaration of objects as well as functions. The basic difference when applied to objects is this:
const declares an object as constant. This implies a guarantee that once initialized, the value of th...
Tools for Generating Mock Data? [closed]
I'm looking for recommendations of a good, free tool for generating sample data for the purpose of loading into test databases. By analogy, something that produces " lorem ipsum " text for any RDBMS. Features I'm looking for include:
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How do you get AngularJS to bind to the title attribute of an A tag?
... tooltip of a thumbnail.
Browsers do not create a tooltip from "ng-title" or "ng-attr-title."
5 Answers
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Keystore type: which one to use?
By looking at the file java.security of my JRE , I see that the keystore type to use by default is set to JKS . Here , there is a list of the keystore types that can be used.
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Mismatched anonymous define() module
I'm getting this error when I browse my webapp for the first time (usually in a browser with disabled cache).
7 Answers
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DESTDIR and PREFIX of make
I am trying to make software install to a specific directory. I found several ways, but not sure what are the differences between them.
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iPhone UIView Animation Best Practice
What is considered best practice for animating view transitions on the iPhone?
8 Answers
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