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Should I use Java date and time classes or go with a 3rd party library like Joda Time?
I'm creating a web based system which will be used in countries from all over the world. One type of data which must be stored is dates and times.
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How to do a simple file search in cmd
...y occurrence of the specified file name within the
specified directory and all subdirectories.
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Omit rows containing specific column of NA
...# 2 2 10 33
EDIT: Only return rows with no NAs
If you want to eliminate all rows with at least one NA in any column, just use the complete.cases function straight up:
DF[complete.cases(DF), ]
# x y z
# 2 2 10 33
Or if completeFun is already ingrained in your workflow ;)
completeFun(DF, na...
Why do you not use C for your web apps?
...t a C program correct and secure. That care means that you need to have really good people writing your programs. That means you pay more.
Also, C doesn't have the benefit of drawing from an enormous single standard library of functionality as .NET (and the other major web-centric platforms) ha...
'any' vs 'Object'
...ate an error telling you exactly that. If you use any instead you are basically telling the transpiler that anything goes, you are providing no information about what is stored in a - it can be anything! And therefore the transpiler will allow you to do whatever you want with something defined as an...
How to clear variables in ipython?
...nd I get bad surprises when variables haven't been cleared. How do I clear all variables?
And is it possible to force this somehow every time I invoke the magic command %run?
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Difference between Visibility.Collapsed and Visibility.Hidden
...have focus, you can't navigate to the control using the TAB key, etcetera, all of which still can if it would have a height and width of zero. But again, in terms of layout, you could say that.
– Razzie
May 20 '09 at 8:45
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Searching word in vim?
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Because the OP asked to search specifically for "word". The solution posted here basically does a search for %word%, whether its thiswordisawesome or word56 or 26word.
– Jguy
Jan 6 '16 at 16:21
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What is the difference between RegExp’s exec() function and String’s match() function?
...egular expression is meant to be used in a loop, as it will still retrieve all matched subexpressions. So:
var re = /[^\/]+/g;
var match;
while (match = re.exec('/a/b/c/d')) {
// match is now the next match, in array form.
}
// No more matches.
String.match does this for you and discards th...
When to use Preorder, Postorder, and Inorder Binary Search Tree Traversal strategies
...efore inspecting any leaves, you pick pre-order because you will encounter all the roots before all of the leaves.
If you know you need to explore all the leaves before any nodes, you select post-order because you don't waste any time inspecting roots in search for leaves.
If you know that the tre...