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How to select rows from a DataFrame based on column values?
... 0 0
# 1 bar one 1 2
# 2 foo two 2 4
# 3 bar three 3 6
# 4 foo two 4 8
# 5 bar two 5 10
# 6 foo one 6 12
# 7 foo three 7 14
print(df.loc[df['A'] == 'foo'])
yields
A B C D
0 foo one 0 0
2 foo two 2 4
4 foo two 4 8
6 f...
How to append multiple values to a list in Python
...; lst.append(4)
>>> lst
[1, 2, 3, 4]
>>> lst.extend([5, 6, 7])
>>> lst.extend((8, 9, 10))
>>> lst
[1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
>>> lst.extend(range(11, 14))
>>> lst
[1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13]
So you can use list.append() t...
Can I initialize a C# attribute with an array or other variable number of arguments?
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edited Dec 1 '16 at 15:56
answered Nov 6 '08 at 20:51
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How to drop columns by name in a data frame
...r the subset function. For example :
R> df <- data.frame(x=1:5, y=2:6, z=3:7, u=4:8)
R> df
x y z u
1 1 2 3 4
2 2 3 4 5
3 3 4 5 6
4 4 5 6 7
5 5 6 7 8
Then you can use the which function and the - operator in column indexation :
R> df[ , -which(names(df) %in% c("z","u"))]
x y
1 1 2...
How to remove specific elements in a numpy array
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306
Use numpy.delete() - returns a new array with sub-arrays along an axis deleted
numpy.delete(a, ...
How do I make the scrollbar on a div only visible when necessary?
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Compare if two variables reference the same object in python
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Does ARC support dispatch queues?
...nd now for the long answer…
If your deployment target is lower than iOS 6.0 or Mac OS X 10.8
You need to use dispatch_retain and dispatch_release on your queue. ARC does not manage them.
If your deployment target is iOS 6.0 or Mac OS X 10.8 or later
ARC will manage your queue for you. You d...
Split a string on whitespace in Go?
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answered Dec 6 '12 at 6:05
I Hate LazyI Hate Lazy
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Aggregate function in an SQL update query?
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