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data.table vs dplyr: can one do something well the other can't or does poorly?
...ll become a column in result. You can use c(), as.list(), lapply(), list() etc... base functions to accomplish this, without having to learn any new functions.
You will need to learn just the special variables - .N and .SD at least. The equivalent in dplyr are n() and .
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dplyr provides s...
SQL Server equivalent to MySQL enum data type?
...ION ActionState_Unassigned()
RETURNS tinyint
AS
BEGIN
RETURN 1
END
-- etc...
Where performance matters, still use the hard values.
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What is object serialization?
... // machine, a database, an in memory array, etc.
new FileOutputStream(new File("o.ser")));
// do the magic
oos.writeObject( instance );
// close the writing.
oos.close();
}
}
When we run this progr...
How to reference generic classes and methods in xml documentation
... For example you need to use Int32 instead of int, Single instead of float etc. (Putting this info here in case anyone else stumbles on this)
– AnorZaken
Mar 13 '15 at 22:17
a...
Inline elements shifting when made bold on hover
...fter, in other words — reset all padding/marging/line-heights/font-sizes etc.
– 350D
Mar 25 '15 at 20:10
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How do I add more members to my ENUM-type column in MySQL?
...UM. ENUM is, at it's core, a mapping of 0 -> Option 1, 1-> Option 2, etc. Adding to that shouldn't cause an issue.
– JoshStrange
Feb 10 '15 at 20:07
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How to find the size of localStorage
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Depends on the character set (i.e. utf8, etc) which that doesn't account for
– jas-
Sep 24 '14 at 11:18
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Replacing NAs with latest non-NA value
...ewhat slower because it does some more checks and handles multiple columns etc.
– Achim Zeileis
Mar 2 '17 at 15:28
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Any reason not to use '+' to concatenate two strings?
... matter of other Python implementations, such as pypy, jython, ironpython, etc...
– jsbueno
Apr 6 '12 at 13:50
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How to tell if a string is not defined in a Bash shell script
... value, ${foo:?error message} to display an error message if foo is unset, etc.
– Jouni K. Seppänen
Oct 23 '08 at 4:54
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