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Sample random rows in dataframe
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460
First make some data:
> df = data.frame(matrix(rnorm(20), nrow=10))
> df
X1 ...
How to concatenate twice with the C preprocessor and expand a macro as in “arg ## _ ## MACRO”?
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edited May 23 '17 at 11:47
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answered Sep 29 '09 at 0:23
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How to overcome TypeError: unhashable type: 'list'
...split('x')"
– Keenan
Dec 3 '12 at 0:43
1
@user1871081 Ah, are you using Python 3.x? I'll post an ...
Difference between '..' (double-dot) and '…' (triple-dot) in range generation?
...e?(5) #=> true
(1...5).include?(5) #=> false
(1..4).include?(4.1) #=> false
(1...5).include?(4.1) #=> true
(1..4).to_a == (1...5).to_a #=> true
(1..4) == (1...5) #=> false
†The docs used to not include this, instead requiring read...
How to delete an element from an array in C#
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342
If you want to remove all instances of 4 without needing to know the index:
LINQ: (.NET Framew...
Exception NoClassDefFoundError for CacheProvider
...ing to implement some simple web application based on Spring 3 + hibernate 4
while I start tomcat I have this exception:
4 ...
How to iterate for loop in reverse order in swift?
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14 Answers
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Append a NumPy array to a NumPy array
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234
In [1]: import numpy as np
In [2]: a = np.array([[1, 2, 3], [4, 5, 6]])
In [3]: b = np.array([...