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Open Redis port for remote connections
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edited Sep 7 '17 at 13:00
answered Sep 30 '13 at 9:53
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Is R's apply family more than syntactic sugar?
... makeSOCKcluster(c("localhost","localhost"))
parSapply(cl, 1:20, get("+"), 3)
This example uses a socket cluster, for which no additional software needs to be installed; otherwise you will need something like PVM or MPI (see Tierney's clustering page). snow has the following apply functions:
par...
List comprehension vs map
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$ python -mtimeit -s'xs=range(10)' 'map(hex, xs)'
100000 loops, best of 3: 4.86 usec per loop
$ python -mtimeit -s'xs=range(10)' '[hex(x) for x in xs]'
100000 loops, best of 3: 5.58 usec per loop
An example of how performance comparison gets completely reversed when map needs a lambda:
$ pytho...
Define a lambda expression that raises an Exception
...7,'|\0\0\202\1\0',(),(),('x',),'','',1,''),{}
)(Exception())
And a python3 strong stomach solution:
type(lambda: 0)(type((lambda: 0).__code__)(
1,0,1,1,67,b'|\0\202\1\0',(),(),('x',),'','',1,b''),{}
)(Exception())
Thanks @WarrenSpencer for pointing out a very simple answer if you don't ca...
How is “int* ptr = int()” value initialization not illegal?
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3
+1, the constant expression bit is important and missing from the top-2 upvoted answers.
– David Rodríguez - dribeas
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Custom Python list sorting
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edited Feb 5 '15 at 17:33
Charlie
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answered Aug 7 '12 at 16:...
How can I initialize a String array with length 0 in Java?
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232
As others have said,
new String[0]
will indeed create an empty array. However, there's one n...
Convert columns to string in Pandas
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355
One way to convert to string is to use astype:
total_rows['ColumnID'] = total_rows['ColumnID'...