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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...
Best way to store time (hh:mm) in a database
I want to store times in a database table but only need to store the hours and minutes.
I know I could just use DATETIME and ignore the other components of the date, but what's the best way to do this without storing more info than I actually need?
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I can’t find the Android keytool
I am trying to follow the Android mapping tutorial and got to this part where I had to get an API key .
10 Answers
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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...
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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What is the difference between 'protected' and 'protected internal'?
Can someone please elaborate me the difference between 'protected' and 'protected internal' modifiers in C#?
It looks they behave in same manner.
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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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What is the difference between “long”, “long long”, “long int”, and “long long int” in C++?
I am transitioning from Java to C++ and have some questions about the long data type. In Java, to hold an integer greater than 2 32 , you would simply write long x; . However, in C++, it seems that long is both a data type and a modifier.
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