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Remove NA values from a vector

...values, and I'm trying to find the max value in that vector (the vector is all numbers), but I can't do this because of the NA values. ...
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If i synchronized two methods on the same class, can they run simultaneously?

... a add on to this question. Suppose both method are static now methodA is called using Class while methodB is called using object like A.methodA() in t1 and obj.methodB() in t2. What will happen now, will they block???? – amod Mar 21 '13 at 12:16 ...
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Is jQuery “each()” function synchronous?

... Yes, the jQuery each method is synchronous. Nearly ALL JavaScript is synchronous. The only exceptions are AJAX, timers (setTimeout and setInterval), and HTML5 Web Workers. Your problem is probably somewhere else in your code. ...
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What is the real overhead of try/catch in C#?

... to make here: Firstly, there is little or NO performance penalty in actually having try-catch blocks in your code. This should not be a consideration when trying to avoid having them in your application. The performance hit only comes into play when an exception is thrown. When an exception is th...
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Bash script error [: !=: unary operator expected

... Or for what seems like rampant overkill, but is actually simplistic ... Pretty much covers all of your cases, and no empty string or unary concerns. In the case the first arg is '-v', then do your conditional ps -ef, else in all other cases throw the usage. #!/bin/sh case $1...
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How to loop over directories in Linux?

I am writing a script in bash on Linux and need to go through all subdirectory names in a given directory. How can I loop through these directories (and skip regular files)? ...
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Fetch the row which has the Max value for a column

... This will retrieve all rows for which the my_date column value is equal to the maximum value of my_date for that userid. This may retrieve multiple rows for the userid where the maximum date is on multiple rows. select userid, my_date, ...
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How to show git log history for a sub directory of a git repo?

...ne -- src/nvfs d6f6b3b Changes for Mac OS X 803fcc3 Initial Commit # Show all changes (one additional commit besides in src/nvfs). $ git log --oneline d6f6b3b Changes for Mac OS X 96cbb79 gitignore 803fcc3 Initial Commit s...
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jquery's append not working with svg element?

...you easy access to the namespaced methods needed to create SVG elements. Really jQuery isn't designed for use with SVG at all and many operations may fail. HTML5 promises to let you use <svg> without an xmlns inside a plain HTML (text/html) document in the future. But this is just a parser ha...
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Cannot install node modules that require compilation on Windows 7 x64/VS2012

I cannot install any of the modules that require compilation. All they fail with the following error: 17 Answers ...