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Grouping functions (tapply, by, aggregate) and the *apply family
Whenever I want to do something "map"py in R, I usually try to use a function in the apply family.
10 Answers
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How do exceptions work (behind the scenes) in c++
I keep seeing people say that exceptions are slow, but I never see any proof. So, instead of asking if they are, I will ask how do exceptions work behind the scenes, so I can make decisions of when to use them and whether they are slow.
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How do you redirect HTTPS to HTTP?
How do you redirect HTTPS to HTTP?. That is, the opposite of what (seemingly) everyone teaches.
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Scala how can I count the number of occurrences in a list
I want to implement it like this: list.count(2) (returns 3).
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How do you iterate through every file/directory recursively in standard C++?
How do you iterate through every file/directory recursively in standard C++?
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Repeat command automatically in Linux
Is it possible in Linux command line to have a command repeat every n seconds?
13 Answers
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What is the argument for printf that formats a long?
...h as %d or %i for a signed int . However, I don't see anything for a long value.
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Telling gcc directly to link a library statically
It feels strange to me to use -Wl,-Bstatic in order to tell gcc which libraries I want to link with statically. After all I'm telling gcc directly all other information about linking with libraries ( -Ldir , -llibname ).
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Way to get number of digits in an int?
Is there a neater way for getting the length of an int than this method?
30 Answers
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Converting Long to Date in Java returns 1970
I have list with long values (for example: 1220227200, 1220832000, 1221436800...) which I downloaded from web service. I must convert it to Dates. Unfortunately this way, for example:
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