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Is it fine to have foreign key as primary key?
...n to this are tables with a one-to-one relationship, where the foreign key and primary key of the linked table are one and the same.
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Remove empty elements from an array in Javascript
...that are falsy, which include an empty string "", 0, NaN, null, undefined, and false.
You can pass to the filter method, the Boolean constructor function, or return the same element in the filter criteria function, for example:
var filtered = array.filter(Boolean);
Or
var filtered = array.filte...
HTML: Include, or exclude, optional closing tags?
...unless I have a very good reason not to) because it lends to more readable and updateable code.
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Why does Math.Round(2.5) return 2 instead of 3?
...ug. C# is the language - it doesn't decide how Math.Round is implemented.
And secondly, no - if you read the docs, you'll see that the default rounding is "round to even" (banker's rounding):
Return ValueType: System.DoubleThe integer nearest a. If the
fractional component of a is halfway
b...
This app won't run unless you update Google Play Services (via Bazaar)
I'm testing out the new Google Maps API V2 for Android, and I'm getting this message when the app launches:
12 Answers
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Moving average or running mean
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UPD: more efficient solutions have been proposed by Alleo and jasaarim.
You can use np.convolve for that:
np.convolve(x, np.ones((N,))/N, mode='valid')
Explanation
The running mean is a case of the mathematical operation of convolution. For the running mean, you slide a win...
How do SO_REUSEADDR and SO_REUSEPORT differ?
The man pages and programmer documentations for the socket options SO_REUSEADDR and SO_REUSEPORT are different for different operating systems and often highly confusing. Some operating systems don't even have the option SO_REUSEPORT . The WEB is full of contradicting information regarding th...
Generating a UUID in Postgres for Insert statement?
My question is rather simple. I'm aware of the concept of a UUID and I want to generate one to refer to each 'item' from a 'store' in my DB with. Seems reasonable right?
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Why is argc not a constant?
...this case, history is a factor. C defined these inputs as "not constant", and compatibility with (a good portion of) existing C code was an early goal of C++.
Some UNIX APIs, such as getopt, actually do manipulate argv[], so it can't be made const for that reason also.
(Aside: Interestingly, al...
How are msys, msys2, and msysgit related to each other?
.... (It's entirely possible I just don't know what to look for.) I do understand that MSYS is a minimal port of Linux tools to support development using MinGW, but I'm not clear on the relationship between the three of them or the teams that developed/maintain them.
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