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How to convert a scala.List to a java.util.List?
...ort scala.collection.jcl.ArrayList
unconvertList(new ArrayList ++ List(1,2,3))
From Scala 2.8 onwards:
import scala.collection.JavaConversions._
import scala.collection.mutable.ListBuffer
asList(ListBuffer(List(1,2,3): _*))
val x: java.util.List[Int] = ListBuffer(List(1,2,3): _*)
However, asLis...
How do I add the contents of an iterable to a set?
...
231
You can add elements of a list to a set like this:
>>> foo = set(range(0, 4))
>>...
HTML5 Canvas Resize (Downscale) Image High Quality?
...e. )
Here's an example of canvas scale vs my pixel perfect scale on a 1/3 scale of a zombat.
Notice that the picture might get scaled in your Browser, and is .jpegized by S.O..
Yet we see that there's much less noise especially in the grass behind the wombat, and the branches on its right. The n...
How can I force division to be floating point? Division keeps rounding down to 0?
...
In Python 2, division of two ints produces an int. In Python 3, it produces a float. We can get the new behaviour by importing from __future__.
>>> from __future__ import division
>>> a = 4
>>> b = 6
>>> c = a / b
>>> c
0.66666666666666663
...
Is generator.next() visible in Python 3?
...
3 Answers
3
Active
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Python “extend” for a dictionary
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phoenix
3,20611 gold badge2727 silver badges3131 bronze badges
answered Feb 23 '09 at 11:01
Nick FortescueNic...
Pandas groupby: How to get a union of strings
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In [5]: df
Out[5]:
A B C
0 1 0.749065 This
1 2 0.301084 is
2 3 0.463468 a
3 4 0.643961 random
4 1 0.866521 string
5 2 0.120737 !
In [6]: df.dtypes
Out[6]:
A int64
B float64
C object
dtype: object
When you apply your own function, t...
What's the difference between lists enclosed by square brackets and parentheses in Python?
...you can change its contents:
>>> x = [1,2]
>>> x.append(3)
>>> x
[1, 2, 3]
while tuples are not:
>>> x = (1,2)
>>> x
(1, 2)
>>> x.append(3)
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
AttributeError: '...
Numbering rows within groups in a data frame
...
answered Oct 16 '12 at 23:41
mnelmnel
103k2424 gold badges240240 silver badges239239 bronze badges
...