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How can I force division to be floating point? Division keeps rounding down to 0?
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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
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Why can't R's ifelse statements return vectors?
...tors, you will get longer results:
> ifelse(c(TRUE, FALSE), c(1, 2), c(3, 4))
[1] 1 4
So ifelse is intended for the specific purpose of testing a vector of booleans and returning a vector of the same length, filled with elements taken from the (vector) yes and no arguments.
It is a common con...
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...
Xcode/Simulator: How to run older iOS version?
...ut what I'm wondering is if I'll still be able to run the simulator as iOS 3.2. This is because I'm creating iAds for iPad but I still want to check if my program will run with iOS 3.2.
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Is generator.next() visible in Python 3?
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3 Answers
3
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Syntax error on print with Python 3 [duplicate]
Why do I receive a syntax error when printing a string in Python 3?
3 Answers
3
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汇编语言（王爽著）附书签 - 文档下载 - 清泛网 - 专注C/C++及内核技术
...自己学，看了很多书，国内像这样的好书真的是很难得。3、更珍贵的是老师的编排，可以说比国外的还好（当然从知识点来说不如国外的书，但是这是一本入门书）
我的感想：1、计算机科学方面的好书，中国基本上没有（运...
Repeat each row of data.frame the number of times specified in a column
...), 1:2]
Result:
var1 var2
1 a d
2 b e
2.1 b e
3 c f
3.1 c f
3.2 c f
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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: '...