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data.table vs dplyr: can one do something well the other can't or does poorly?
...n shallow copied DT
DT[x > 2L, x := 3L] ## have to copy (like base R / dplyr does always); otherwise original DT will
## also get modified.
}
By not using shallow(), the old functionality is retained:
bar <- function(DT) {
DT[, newcol := 1L] ...
Hidden Features of Java
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So you interview based on Java trivia rather than on aptitude to solve problems and think through designs. I'll make sure I never interview with your company. :)
– Javid Jamae
Aug 24 '10 at 20:35
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Disable spell-checking on HTML textfields
... for help, clarification, or responding to other answers.Making statements based on opinion; back them up with references or personal experience.To learn more, see our tips on writing great answers.
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How to make a Python script run like a service or daemon in Linux
...ass the Daemon class and override the run() method
"""
def __init__(self, pidfile, stdin='/dev/null', stdout='/dev/null', stderr='/dev/null'):
self.stdin = stdin
self.stdout = stdout
self.stderr = stderr
self.pidfile = p...
Alter Table Add Column Syntax
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In a relational database, you should never have a need for the ordinality of the columns so if you are trying to neatly order the columns, the question is why? If column ordinality was so important, why isn't there a trivial function to swap or ...
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if (isset($_COOKIE['remember_user'])) {
unset($_COOKIE['remember_user']);
setcookie('remember_user', null, -1, '/');
return true;
} else {
return false;
}
...
Cleanest way to get last item from Python iterator
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item = defaultvalue
for item in my_iter:
pass
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How do I run Python code from Sublime Text 2?
... find out where your Break key is here: http://en.wikipedia.org/wiki/Break_key.
Note: CTRL + C will NOT work.
What to do when Ctrl + Break does not work:
Go to:
Preferences -> Key Bindings - User
and paste the line below:
{"keys": ["ctrl+shift+c"], "command": "exec", "args": {"k...
Why can templates only be implemented in the header file?
... sentence at the very start of this answer to clarify that the question is based on a false premise. If somebody asks "Why is X true?" when in fact X is not true, we should quickly reject that assumption.
– Aaron McDaid
Aug 5 '15 at 9:39
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TypeError: 'NoneType' object is not iterable in Python
...r a variable containing None. The operation was performed by invoking the __iter__ method on the None.
None has no __iter__ method defined, so Python's virtual machine tells you what it sees: that NoneType has no __iter__ method.
This is why Python's duck-typing ideology is considered bad. The...