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Don't understand why UnboundLocalError occurs (closure) [duplicate]
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counter += 1
implicitly makes counter local to increment(). Trying to execute this line, though, will try to read the value of the local variable counter before it is assigned, resulting in an UnboundLocalError.[2]
If counter is a global variable, the global keyword will help. If increment() i...
Scroll to a div using jquery
so I have a page that has a fixed link bar on the side. I'd like to scroll to the different divs. Basically the page is just one long website, where I'd like to scroll to different divs using the menu box to the side.
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Haskell: How is pronounced? [closed]
...icative type class sits somewhere between Functor and Monad, so one would expect it to have a similar mathematical basis. The documentation for the Control.Applicative module begins with:
This module describes a structure intermediate between a functor and a monad: it provides pure expressions a...
Getting Checkbox Value in ASP.NET MVC 4
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@Html.EditorFor(x => x.Remember)
Will generate:
<input id="Remember" type="checkbox" value="true" name="Remember" />
<input type="hidden" value="false" name="Remember" />
How does it work:
If checkbox remains unchecked,...
Generate random number between two numbers in JavaScript
...esults into 0.99 our random value would be 7
– antitoxic
Dec 12 '13 at 16:15
29
This code not goo...
Why is NaN not equal to NaN? [duplicate]
...ulations, infecting them like a virus, so if somewhere in your deep, complex calculations you hit upon a NaN, you don't bubble out a seemingly sensible answer. Otherwise by identity NaN/NaN should equal 1, along with all the other consequences like (NaN/NaN)==1, (NaN*1)==NaN, etc. If you imagine tha...
Why does NULL = NULL evaluate to false in SQL server
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Think of the null as "unknown" in that case (or "does not exist"). In either of those cases, you can't say that they are equal, because you don't know the value of either of them. So, null=null evaluates to not true (false or null, depending on your system), because you don't know ...
What are the GCC default include directories?
...e default paths used by gcc/g++, as well as their priorities, you need to examine the output of the following commands:
For C:
gcc -xc -E -v -
For C++:
gcc -xc++ -E -v -
The credit goes to Qt Creator team.
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Aligning rotated xticklabels with their respective xticks
Check the x axis of the figure below. How can I move the labels a bit to the left so that they align with their respective ticks?
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Why is pow(a, d, n) so much faster than a**d % n?
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See the Wikipedia article on modular exponentiation. Basically, when you do a**d % n, you actually have to calculate a**d, which could be quite large. But there are ways of computing a**d % n without having to compute a**d itself, and that is what pow does. Th...