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How to combine multiple conditions to subset a data-frame using “OR”?
... the following syntax before with lot of success when I wanted to use the "AND" condition.
3 Answers
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Difference between reduce and foldLeft/fold in functional programming (particularly Scala and Scala
Why do Scala and frameworks like Spark and Scalding have both reduce and foldLeft ? So then what's the difference between reduce and fold ?
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Why can't I initialize non-const static member or static array in class?
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Why I can't initialize static data members in class?
The C++ standard allows only static constant integral or enumeration types to be initialized inside the class. This is the reason a is allowed to be initialized while others are not.
Reference:
C++03 9.4.2 Static data members
§4
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Why does SIGPIPE exist?
From my understanding, SIGPIPE can only occur as the result of a write() , which can (and does) return -1 and set errno to EPIPE ... So why do we have the extra overhead of a signal? Every time I work with pipes I ignore SIGPIPE and have never felt any pain as a result, am I missing somethin...
How do I address unchecked cast warnings?
...d have the generic parameters <String, String>. You must know beforehand what the parameters should be (or you'll find out when you get a ClassCastException). This is why the code generates a warning, because the compiler can't possibly know whether is safe.
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Intellij IDEA Java classes not auto compiling on save
...+Shift+A on Mac) type Registry once the registry windows is open, locate and enable compiler.automake.allow.when.app.running, see here:
For versions older than 12, you can use the EclipseMode plugin to make IDEA automatically compile the saved files.
For more tips see the "Migrating From Eclips...
How to overload std::swap()
std::swap() is used by many std containers (such as std::list and std::vector ) during sorting and even assignment.
4 A...
Using Rails 3.1, where do you put your “page specific” JavaScript code?
To my understanding, all of your JavaScript gets merged into 1 file. Rails does this by default when it adds //= require_tree . to the bottom of your application.js manifest file.
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Combine the first two commits of a Git repository?
Suppose you have a history containing the three commits A, B and C :
8 Answers
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Wget output document and headers to STDOUT
I'm trying to output document body and its headers to stdout with wget by wget -S -O - http://google.com
5 Answers
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