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Read an Excel file directly from a R script
...d to look at your numbers" ... what is the issue with "-" fields? does na.strings="-" address the problem? How many of these issues are generic and how many of them (e.g. numeric fields with commas) can be addressed with other tools such as XLConnect ...?
– Ben Bolker
...
MySQL “NOT IN” query
... it is possible that the code responsible for EXISTS makes some kind of an extra check which takes extra time.
[…]
MySQL can optimize all three methods to do a sort of NESTED LOOPS ANTI JOIN.
[…]
However, these three methods generate three different plans which are executed by three di...
Really Cheap Command-Line Option Parsing in Ruby
...eractive, "Be interactive"
opt :filename, "File to process", :type => String
end
And that's it. opts is now a hash with keys :quiet, :interactive, and :filename. You can do whatever you want with it. And you get a beautiful help page, formatted to fit your screen width, automatic short argume...
What's “requestCode” used for on PendingIntent?
...e Context target, and the Intent object you are passing differ only in the EXTRA_DATA (which specifies the date that should be open). If you provide the same requestCode when obtaining the PendingIntent object, then you will end up with the same PendingIntent object. So, when creating the second not...
How to implement classic sorting algorithms in modern C++?
... cmp = Compare{});
In C++11, one can define a reusable template alias to extract an iterator's value type which adds minor clutter to the sort algorithms' signatures:
template<class It>
using value_type_t = typename std::iterator_traits<It>::value_type;
template<class It, class Co...
event Action vs event EventHandler
... you don't get named parameters, so if you're passing 3 bool's an int, two string's, and a DateTime, you have no idea what the meaning of those values are. As a side note, you can still have a "Fire this event safely method while still using Action<T1, T2, T2... >".
Secondly, consistency impl...
Why it's not possible to use regex to parse HTML/XML: a formal explanation in layman's terms
... of regular expressions is equivalent to the fact that a test of whether a string matches the pattern can be performed by a finite automaton (one different automaton for each pattern). A finite automaton has no memory - no stack, no heap, no infinite tape to scribble on. All it has is a finite numbe...
Favorite Visual Studio keyboard shortcuts [closed]
...and keeps you in search mode (which means you can add or change the search string). The search box is for suckers!
– Aardvark
Oct 4 '08 at 19:59
9
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if (key in object) or if(object.hasOwnProperty(key)
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@Lor: ({foo:"bar"}).hasOwnProperty("toString") vs "toString" in ({foo:"bar"})
– I Hate Lazy
Nov 29 '12 at 19:24
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Determining memory usage of objects? [duplicate]
... 4125 1359 6963 49425
special builtin char logical integer double complex
173 1562 20652 7383 13212 4137 1
(There's another function, memory.size() but i have heard and read that it only seems to...