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How unique is UUID?
...ify something (I'm using it for files uploaded to the server)? As I understand it, it is based off random numbers. However, it seems to me that given enough time, it would eventually repeat it self, just by pure chance. Is there a better system or a pattern of some type to alleviate this issue?
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Remove rows with all or some NAs (missing values) in data.frame
... 1 2 3 2
but using complete.cases is quite a lot more clear, and faster.
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Does Notepad++ show all hidden characters?
... *Show All Characters`
or
Menu View → Show Symbol → Show White Space and TAB
(Thanks to bers' comment and bkaid's answers below for these updated locations.)
On older versions you can look for:
Menu View → Show all characters
or
Menu View → Show White Space and TAB
...
What should I name a table that maps two tables together? [closed]
...There are only two hard things in
Computer Science: cache invalidation
and naming things-- Phil Karlton
Coming up with a good name for a table that represents a many-to-many relationship makes the relationship easier to read and understand. Sometimes finding a great name is not trivial but usu...
Should I put #! (shebang) in Python scripts, and what form should it take?
...line in any script determines the script's ability to be executed like a standalone executable without typing python beforehand in the terminal or when double clicking it in a file manager (when configured properly). It isn't necessary but generally put there so when someone sees the file opened in ...
Including all the jars in a directory within the Java classpath
...ion. See also: Execute jar file with multiple classpath libraries from command prompt)
Understanding Wildcards
From the Classpath document:
Class path entries can contain the basename wildcard character *, which is considered equivalent to specifying a list of all the files
in the directory with th...
What are the pros and cons of git-flow vs github-flow? [closed]
...a process for managing changes in Git that was created by Vincent Driessen and accompanied by some Git extensions for managing that flow.
The general idea behind git-flow is to have several separate branches that always exist, each for a different purpose: master, develop, feature, release, and ho...
Returning multiple values from a C++ function
...a C++ function? For example, imagine a function that divides two integers and returns both the quotient and the remainder. One way I commonly see is to use reference parameters:
...
OAuth: how to test with local URLs?
...ake sure that www.publicdomain.com points to 127.0.0.1 in your hosts file, AND that twitter can do a successful DNS lookup on www.publicdomain.com, i.e the domain needs to exist and the specific callback should probably return a 200 status message if requested.
EDIT:
I just read the following articl...
Why does ~True result in -2?
...
int(True) is 1.
1 is:
00000001
and ~1 is:
11111110
Which is -2 in Two's complement1
1 Flip all the bits, add 1 to the resulting number and interpret the result as a binary representation of the magnitude and add a negative sign (since the number begins...