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Why does X[Y] join of data.tables not allow a full outer join, or a left join?
...bit of a philosophical question about data.table join syntax. I am finding more and more uses for data.tables, but still learning...
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Easiest way to detect Internet connection on iOS?
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I did a little more research and I am updating my answer with a more current solution. I am not sure if you have already looked at it but there is a nice sample code provided by Apple.
Download the sample code here
Include the Reachab...
Why switch is faster than if
... Please constrain "long". Greater than 5? Greater than 10? or more like 20 - 30?
– egerardus
Jan 17 '12 at 18:25
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Effective way to find any file's Encoding
...king at the reference source for StreamReader, that implementation is what more people will want. They make new encodings rather than using the existing Encoding.Unicode objects, so equality checks will fail (which might rarely happen anyway because, for instance, Encoding.UTF8 can return different ...
How does Python's super() work with multiple inheritance?
...t have the attribute, then it will look at Second.
This situation becomes more complex when inheritance starts crossing paths (for example if First inherited from Second). Read the link above for more details, but, in a nutshell, Python will try to maintain the order in which each class appears on ...
Counting DISTINCT over multiple columns
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Excellent suggestion! The more I read, the more I am realizing that SQL is less about knowing syntax and functions and more about applying pure logic.. I wish I had 2 upvotes!
– tumchaaditya
Oct 4 '13 at 22:48
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Why malloc+memset is slower than calloc?
...) will first try to get 16 bytes out of one of its pools, and then ask for more memory from the kernel when the pool runs dry. However, since the program you're asking about is allocating for a large amount of memory at once, malloc() and calloc() will just ask for that memory directly from the ker...
Why we should not use protected static in java
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It's more a stylistic thing than a direct problem. It suggests that you haven't properly thought through what is going on with the class.
Think about what static means:
This variable exists at class level, it does not exist s...
What is the benefit of using $() instead of backticks in shell scripts?
...kdb you're right about the x=$(f) working without quotes. I should've been more specific; I was proposing to use libdir=$(dirname "$(dirname "$(which gcc)")")/lib (quotes around the inner command substitutions). If left unquoted, you are still subject to the usual word splitting and glob expansion.
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