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How to force R to use a specified factor level as reference in a regression?
...ommand which is the best solution if you want to change the base level for all analyses on your data (or are willing to live with changing the data).
If you don't want to change the data (this is a one time change, but in the future you want the default behavior again), then you can use a combinati...
How to make/get a multi size .ico file? [closed]
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I had all the images already, delivered by the artist for mac. All I had to do was open one of them in Gimp, and the choose "Open as layers.." on the remaining ones. All layers are automatically created in the correct size, export ...
What characters are valid for JavaScript variable names?
...ou an idea of how wrong Anthony Mills' answer is: if you were to summarize all these rules in a single ASCII-only regular expression for JavaScript, it would be 11,236 characters long. Here it is:
// ES5.1 / Unicode 6.1
/^(?!(?:do|if|in|for|let|new|try|var|case|else|enum|eval|false|null|this|true|v...
Why is sed not recognizing \t as a tab?
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Not all versions of sed understand \t. Just insert a literal tab instead (press Ctrl-V then Tab).
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What is The Rule of Three?
...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), age(age)
{
}
};
int main()
{
person a("Bjar...
How to query MongoDB with “like”?
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Actually, it depends. If the query doesn't use an index, and must do a table scan, then it can certainly be expensive. If you're doing a 'starts with' regex query, then that can use an index. Best to run an explain() to see what'...
Check if list contains any of another list
...ould be to project parameters to source and then use Intersect which internally uses a HashSet<T> so instead of O(n^2) for the first approach (the equivalent of two nested loops) you can do the check in O(n) :
bool hasMatch = parameters.Select(x => x.source)
.Inte...
How do you install Boost on MacOS?
How do you install Boost on MacOS?
Right now I can't find bjam for the Mac.
10 Answers
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Automatically plot different colored lines
...t several kernel density estimations on the same graph, and I want them to all be different colors. I have a kludged solution using a string 'rgbcmyk' and stepping through it for each separate plot, but I start having duplicates after 7 iterations. Is there an easier/more efficient way to do this,...
Why do I have to access template base class members through the this pointer?
...emplate parameter. Others are deferred until the parameter is known. It's called two-phase compilation, and MSVC doesn't do it but it's required by the standard and implemented by the other major compilers. If you like, the compiler must compile the template as soon as it sees it (to some kind of in...