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How to convert a factor to integer\numeric without loss of information?
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The most easiest way would be to use unfactor function from package varhandle
unfactor(your_factor_variable)
This example can be a quick start:
x <- rep(c("a", "b", "c"), 20)
y <- rep(c(1, 1, 0), 20)
class(x) # -> "character"
class(y) # -> "numeric"
x <- fa...
Wrapping null-returning method in Java with Option in Scala?
...don't know whether it will return you a string or a null, because it comes from Java.
4 Answers
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Maintaining the final state at end of a CSS3 animation
...ion class is applied onClick, and, using keyframes, it changes the opacity from 0 to 1 (among other things).
4 Answers
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How to make pipes work with Runtime.exec()?
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Create a Runtime to run each of the process. Get the OutputStream from the first Runtime and copy it into the InputStream from the second one.
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simulate background-size:cover on or
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just a comment to prevent newbies from pulling their hair out: #video_background{ should be #videobackground{.
– carrabino
Oct 28 '13 at 2:26
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How to dynamically build a JSON object with Python?
...e a preferred representation of your concept.
pip install objdict first.
from objdict import ObjDict
data = ObjDict()
data.key = 'value'
json_data = data.dumps()
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What is “(program)” in Chrome debugger’s profiler?
... the root of the tree calling all other code...it's there because the jump from native code to JavaScript, resource loading, etc. has to start somewhere :)
You can see examples of the treeview in the Chrome developer tool docs.
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Why is i++ not atomic?
...d be inappropriate to use the atomic i++. What's worse, programmers coming from C or other C-like languages to Java would use i++ anyway, resulting in unnecessary use of atomic instructions.
Even at the machine instruction set level, an increment type operation is usually not atomic for performance...
Pragma in define macro
..._pragma() preprocessor operator, which unfortunately is slightly different from C99's _Pragma() operator (C99's takes a string literal, MSVC's takes tokens that aren't in a string): msdn.microsoft.com/en-us/library/d9x1s805.aspx
– Michael Burr
Jun 13 '10 at 16:...
Is there anything like .NET's NotImplementedException in Java?
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It appears that NotImplementedException has been removed from Commons Lang 3.0.
– Michael Younkin
Aug 19 '11 at 15:17
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