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Applying a function to every row of a table using dplyr?
...mically formed datatframe? So in this data frame the column names are not known. I am able to add if column names are known.
– Arun Raja
May 4 '15 at 7:49
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What algorithm can be used for packing rectangles of different sizes into the smallest rectangle pos
... I was just playing with something like that on a bit of paper, right now looks fairly optimal in most cases, even without rotating the rectangles or anything
– Fire Lancer
Jul 31 '09 at 16:37
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DateTime vs DateTimeOffset
... Whenever we produce a DateTime we do it in UTC (e.g. using DateTime.UtcNow ), and whenever we display one, we convert back from UTC to the user's local time.
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Parse JSON in TSQL
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Update: As of SQL Server 2016 parsing JSON in TSQL is now possible.
Natively, there is no support. You'll have to use CLR. It is as simple as that, unless you have a huge masochistic streak and want to write a JSON parser in SQL
Normally, folk ask for JSON output from the DB ...
What's the difference between lapply and do.call?
...he above means something like below.
list( sum( L[[1]]) , sum( L[[2]]))
Now let us do the same thing for do.call
do.call(sum, L)
It means
sum( L[[1]], L[[2]])
In our example, it returns 21. In short, lapply always returns a list while the return type of do.call really depends on the funct...
Programmatic equivalent of default(Type)
...oop through a Type 's properties and set certain types to their default. Now, I could do a switch on the type and set the default(Type) explicitly, but I'd rather do it in one line. Is there a programmatic equivalent of default?
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Why are function pointers and data pointers incompatible in C/C++?
... pointer to objects.
The C99 Rationale says:
6.3.2.3 Pointers
C has now been implemented on a wide range of architectures. While some of these
architectures feature uniform pointers which are the size of some integer type, maximally
portable code cannot assume any necessary correspondence...
Why was the arguments.callee.caller property deprecated in JavaScript?
...ifficult.
Eg. if we can't guarantee that a function f will not call an unknown function, then it is not possible to inline f. Basically it means that any call site that may have been trivially inlinable accumulates a large number of guards, take:
function f(a, b, c, d, e) { return a ? b * c : d *...
Difference between Pragma and Cache-Control headers?
...that actually might mean to returning stale content to the clients, WHAT?? Now you forget this and read the above simple answer and enjoy your life, don't dig it too hard lol
– sotn
Mar 3 '16 at 21:29
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How can I open a Shell inside a Vim Window?
...y horizontal splits without a patch) to split your terminal. But I do not know the way to have one instance of Vim in both panes.
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