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Reshaping data.frame from wide to long format
...alues (as a result of the , in the numbers). You can repair that with gsub and as.numeric:
long$value <- as.numeric(gsub(",", "", long$value))
Or directly with data.table or dplyr:
# data.table
long <- melt(setDT(wide),
id.vars = c("Code","Country"),
variable.name...
Is it possible to animate scrollTop with jQuery?
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Why do you need both html and body? There is some insight here: stackoverflow.com/questions/2123690/…, but it is not a complete answer.
– Haralan Dobrev
Dec 13 '13 at 15:22
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What's the difference between std::move and std::forward
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std::move takes an object and allows you to treat it as a temporary (an rvalue). Although it isn't a semantic requirement, typically a function accepting a reference to an rvalue will invalidate it. When you see std::move, it indicates that the value ...
C#: Abstract classes need to implement interfaces?
...mpiler that you are deliberately passing the buck to concrete subclasses - and the above line of code shows how to do so.
The comments and downvotes complaining that this is not an answer to the question are missing the point. Someone coming to Stack Overflow, having received this compiler error, b...
Performance optimization strategies of last resort [closed]
...ite already, but it occurs to me that almost all are very problem-specific and fairly narrow. And almost all repeat the advice to avoid premature optimization.
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How to initialize private static members in C++?
...variable is of const int type (e.g. int, bool, char). You can then declare and initialize the member variable directly inside the class declaration in the header file:
class foo
{
private:
static int const i = 42;
};
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How to get the value from the GET parameters?
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JavaScript itself has nothing built in for handling query string parameters.
Code running in a (modern) browser you can use the URL object (which is part of the APIs provided by browsers to JS):
var url_string = "http://www.example.com/t.html?a=1&b=3&c=m...
Difference between local and global indexes in DynamoDB
I'm curious about these two secondary indexes and differences between them. It is hard to imagine how this looks like. And I think, this will help more people than just me.
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Chrome: Uncaught SyntaxError: Unexpected end of input
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ok Thanks alot i removed the json request all together and the error went away i've yet to figure out what exactly is wrong with my json request. i just had no idea where to start debugging. if i may ask how did you determine the root cause
– dlaurent86
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How to count the number of occurrences of an element in a List
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I'm pretty sure the static frequency-method in Collections would come in handy here:
int occurrences = Collections.frequency(animals, "bat");
That's how I'd do it anyway. I'm pretty sure this is jdk 1.6 straight up.
shar...