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What does .SD stand for in data.table in R
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How do you copy the contents of an array to a std::vector in C++ without looping?
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phoenix
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answered Nov 3 '08 at 17:38
Drew HallDrew Hall...
object==null or null==object?
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answered Mar 3 '10 at 6:39
Laurence GonsalvesLaurence Gonsalves
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Variable declared in for-loop is local variable?
...l variable declared in a for-initializer of a for
statement (Section 8.8.3) is the for-initializer, the for-condition,
the for-iterator, and the contained statement of the for statement.
And also: Local variable declarations (Section 8.5.1 of the C# specification)
Specifically:
The scope ...
count the frequency that a value occurs in a dataframe column
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What is the difference between ui-bootstrap-tpls.min.js and ui-bootstrap.min.js?
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Python 3 turn range to a list
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You can just construct a list from the range object:
my_list = list(range(1, 1001))
This is ...
Apply pandas function to column to create multiple new columns?
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Efficient way to apply multiple filters to pandas DataFrame or Series
...'col1'] >= 1]
Out[12]:
col1 col2
1 1 11
2 2 12
In [13]: df[(df['col1'] >= 1) & (df['col1'] <=1 )]
Out[13]:
col1 col2
1 1 11
If you want to write helper functions for this, consider something along these lines:
In [14]: def b(x, col, op, n):
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Delete specific line number(s) from a text file using sed?
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384
If you want to delete lines 5 through 10 and 12:
sed -e '5,10d;12d' file
This will print th...