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Why do we need a pure virtual destructor in C++?
...dn't deduce a good reason to actually use a pure virtual destructor. For example, the following reason doesn't convince me at all:
Probably the real reason that pure virtual destructors are allowed is that to prohibit them would mean adding another rule to the language and there's no need for th...
What is the purpose of wrapping whole Javascript files in anonymous functions like “(function(){ … }
...
function private_function() {
//code
}
})();
In the first example, you would explicitly invoke globalFunction by name to run it. That is, you would just do globalFunction() to run it. But in the above example, you're not just defining a function; you're defining and invoking it in one...
How to go to a specific element on page? [duplicate]
...llIntoView(eleID) {
var e = document.getElementById(eleID);
if (!!e && e.scrollIntoView) {
e.scrollIntoView();
}
}
This even works in an IFrame on an iPhone.
Example of using getElementById:
http://www.w3schools.com/jsref/tryit.asp?filename=tryjsref_document_getelementbyid...
How do I check if an element is really visible with JavaScript? [duplicate]
... in_viewport = r.top > 0 ? r.top <= height : (r.bottom > 0 && r.bottom <= height);
if (in_viewport && on_top(r)) return true;
}
return false;
}
It checks that the element has an area > 0 and then it checks if any part of the element is within the viewpo...
How do I know the script file name in a Bash script?
... want to confuse the user this way), try:
me="$(basename "$(test -L "$0" && readlink "$0" || echo "$0")")"
IMO, that'll produce confusing output. "I ran foo.sh, but it's saying I'm running bar.sh!? Must be a bug!" Besides, one of the purposes of having differently-named symlinks is to...
Why do some C# lambda expressions compile to static methods?
...
This is most likely because there are no closures, for example:
int age = 25;
Action<string> withClosure = s => Console.WriteLine("My name is {0} and I am {1} years old", s, age);
Action<string> withoutClosure = s => Console.WriteLine("My name is {0}", s);
...
How do I open an old MVC project in Visual Studio 2012 or Visual Studio 2013?
...unsupported MVC project in Visual Studio 2012 or Visual Studio 2013 is actually pretty easy to accomplish with two steps. In fact, as bytebender’s comment indicates, these same steps should apply to and work for MVC 1 projects. However, I haven’t tested them and therefore cannot guarantee that t...
Convert Elixir string to integer or float
...at is tougher:
iex()> "1 2 3 10 100" |> String.split |> Enum.map(&String.to_integer/1)
[1, 2, 3, 10, 100]
iex()> "1.0 1 3 10 100" |> String.split |> Enum.map(&String.to_float/1)
** (ArgumentError) argument error
:erlang.binary_to_float("1")
(elixir) lib/enum.ex:127...
How do I install pip on macOS or OS X?
...d for me instead. curl https://bootstrap.pypa.io/get-pip.py -o get-pip.py && sudo python get-pip.py
– user2975337
Apr 22 '18 at 1:55
...
Transposing a NumPy array
...pair.
import numpy as np
a = np.array([[5, 4]])
a.T
More thorough example:
>>> a = [3,6,9]
>>> b = np.array(a)
>>> b.T
array([3, 6, 9]) #Here it didn't transpose because 'a' is 1 dimensional
>>> b = np.array([a])
>>> b.T
array([[3], ...