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Grouping functions (tapply, by, aggregate) and the *apply family
...ed by the extremely popular plyr package, the base functions remain useful and worth knowing.
This answer is intended to act as a sort of signpost for new useRs to help direct them to the correct *apply function for their particular problem. Note, this is not intended to simply regurgitate or repla...
What is the difference between a Docker image and a container?
...en using Docker, we start with a base image. We boot it up, create changes and those changes are saved in layers forming another image.
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What is The Rule of Three?
...antics.
This means that objects are implicitly copied in various contexts,
and we should understand what "copying an object" actually means.
Let us consider a simple example:
class person
{
std::string name;
int age;
public:
person(const std::string& name, int age) : name(name), ag...
Why does 2 mod 4 = 2?
...ion. My term does not start for two more weeks so I can't ask a professor, and the suspense would kill me.
19 Answers
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What's the difference between a word and byte?
I've done some research.
A byte is 8 bits and a word is the smallest unit that can be addressed on memory. The exact length of a word varies. What I don't understand is what's the point of having a byte? Why not say 8 bits?
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iOS 6: How do I restrict some views to portrait and allow others to rotate?
...vels deep. I want the first three views restricted to portrait orientation and only the last view should be allowed to rotate to landscape. When returning from the fourth view to the third and the fourth view was in landscape orientation I want everything to rotate back to portrait.
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List of macOS text editors and code editors [closed]
I searched for this and found Maudite's question about text editors but they were all for Windows.
39 Answers
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Android Studio: how to remove/update the “Created by” comment added to all new classes?
By default Android Studio automatically adds a header comment to all new classes, e.g.
9 Answers
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What's the point of Spring MVC's DelegatingFilterProxy?
...ds a bean ("target bean" or "delegate") in your Spring application context and invokes it. How is it possible? Because this bean implements javax.servlet.Filter, its doFilter method is called.
Which bean is called? the DelegatingFilterProxy "Supports a "targetBeanName" [...], specifying the name of...
Returning a boolean from a Bash function
... want to write a bash function that check if a file has certain properties and returns true or false. Then I can use it in my scripts in the "if". But what should I return?
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