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Replacing NAs with latest non-NA value

...ewhat slower because it does some more checks and handles multiple columns etc. – Achim Zeileis Mar 2 '17 at 15:28 add a comment  |  ...
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Any reason not to use '+' to concatenate two strings?

... matter of other Python implementations, such as pypy, jython, ironpython, etc... – jsbueno Apr 6 '12 at 13:50 add a comment  |  ...
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How to tell if a string is not defined in a Bash shell script

... value, ${foo:?error message} to display an error message if foo is unset, etc. – Jouni K. Seppänen Oct 23 '08 at 4:54 add a comment  |  ...
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getenv() vs. $_ENV in PHP

...or the getenv function, this is because there are three ways that PHP can fetch the environment variable: Via sapi_getenv (e.g. if it's getting the environment variable from Apache) If on Windows, from GetEnvironmentVariableA. If on non-Windows, from the getenv function provided by libc. As far ...
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DESTDIR and PREFIX of make

...hat it's worth, in a cmake-based build you can emulate "case 4" (for stow, etc) by running cmake -DCMAKE_INSTALL_PREFIX=/foo/bar/baz -P cmake_install.cmake in the build directory. – Ryan Pavlik Sep 6 '12 at 17:12 ...
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Twitter API returns error 215, Bad Authentication Data

... A very concise code without any other php file include of oauth etc. Please note to obtain following keys you need to sign up with https://dev.twitter.com and create application. <?php $token = 'YOUR_TOKEN'; $token_secret = 'YOUR_TOKEN_SECRET'; $consumer_key = 'CONSUMER_KEY'; $consume...
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jQuery .hasClass() vs .is()

... is is multi-purpose, you can for example do is('.class'), is(':checked'), etc which means is has more to do where is hasClass is limited which only checks for a class being set or not. Hence, hasClass should be faster if performance at any level is your priority. ...
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How can I get nth element from a list?

...hat the standard library contains some such partial functions (head, last, etc.). For safety, use an option type Maybe, or the Safe module. Example of a reasonably efficient, robust total (for indices ≥ 0) indexing function: data Maybe a = Nothing | Just a lookup :: Int -> [a] -> Maybe a ...
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What is the difference between “def” and “val” to define a function

... x % 2 == 0)" function (not any other statement before i.e. println("val") etc. Invoking event2 with different parameters will actually invoke "(x => x % 2 == 0)" code, as only that is saved with event2. scala> even2(2) res7: Boolean = true scala> even2(3) res8: Boolean = false Just to ...
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jQuery: keyPress Backspace won't fire?

...is; setTimeout( function(){ /** Code that processes backspace, etc. **/ }, 100 ); } ); share | improve this answer | follow | ...