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How do I make a column unique and index it in a Ruby on Rails migration?
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answered Sep 19 '09 at 20:39
ndpndp
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removeEventListener on anonymous functions in JavaScript
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Mean per group in a data.frame [duplicate]
....table(text=
'Name Month Rate1 Rate2
Aira 1 12 23
Aira 2 18 73
Aira 3 19 45
Ben 1 53 19
Ben 2 22 87
Ben 3 19 45
Cat 1 22 87
Cat 2 67 43
Cat ...
if arguments is equal to this string, define a variable like this string
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Methods inside enum in C#
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answered May 12 '11 at 23:30
MarkPflugMarkPflug
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C++ const map element access
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edited Aug 28 '13 at 14:38
user283145
answered Feb 27 '11 at 17:29
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How can I pass a parameter to a Java Thread?
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377
You need to pass the parameter in the constructor to the Runnable object:
public class MyRunn...
IEnumerable vs List - What to Use? How do they work?
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edited Nov 22 '15 at 20:53
Amirhossein Mehrvarzi
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Extract date (yyyy/mm/dd) from a timestamp in PostgreSQL
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kworr
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answered May 26 '11 at 2:40
Wayne ConradWayne ...
how does multiplication differ for NumPy Matrix vs Array classes?
...find it more trouble than it's worth, though.
For arrays (prior to Python 3.5), use dot instead of matrixmultiply.
E.g.
import numpy as np
x = np.arange(9).reshape((3,3))
y = np.arange(3)
print np.dot(x,y)
Or in newer versions of numpy, simply use x.dot(y)
Personally, I find it much more read...