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Remove empty elements from an array in Javascript
...ments that pass the criteria of the callback function you provide to it.
For example, if you want to remove null or undefined values:
var array = [0, 1, null, 2, "", 3, undefined, 3,,,,,, 4,, 4,, 5,, 6,,,,];
var filtered = array.filter(function (el) {
return el != null;
});
console....
When you exit a C application, is the malloc-ed memory automatically freed?
...
It depends on the operating system. The majority of modern (and all major) operating systems will free memory not freed by the program when it ends.
Relying on this is bad practice and it is better to free it explicitly. The issue isn't just that your code looks bad....
How to redirect to Index from another controller?
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Ok this worked. I tried this earlier must of been a typo when I did it before.
– cjohnson2136
Oct 25 '11 at 16:05
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How to overload functions in javascript?
...rguments passed to it.
Default arguments - You can define a default value for an argument if it is not passed.
Named arguments - Argument order becomes irrelevant and you just name which arguments you want to pass to the function.
Below is a section on each of these categories of argument handling...
The term “Context” in programming? [closed]
I have been programming for some months now and a frequently used word is "context" in classes. Like ServletContext (Java), Activity (Android), Service (Java, Android), NSManagedContext (Objective-C, iOS).
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Why does auto a=1; compile in C?
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auto is an old C keyword that means "local scope". auto a is the same as auto int a, and because local scope is the default for a variable declared inside a function, it's also the same as int a in this example.
This keyword is actually a leftov...
decimal vs double! - Which one should I use and when? [duplicate]
...use a double and when should I use a decimal type?
Which type is suitable for money computations? (ie. greater than $100 million)
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biggest integer that can be stored in a double
What is the biggest "no-floating" integer that can be stored in an IEEE 754 double type without losing precision ?
7 Answer...
What is
...s of T, it is saying it has to be a superclass of T. The distinction is important because extends tells you what you can get out of a class (you get at least this, perhaps a subclass). super tells you what you can put into the class (at most this, perhaps a superclass).
In this specific case, what ...
To find whether a column exists in data frame or not
... dat and that your column name to check is "d", you can use the %in% operator:
if("d" %in% colnames(dat))
{
cat("Yep, it's in there!\n");
}
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