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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 to get the nth element of a python list or a default if not available
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gruszczygruszczy
35.8k2626 gold badges113113 silver badges163163 bronze badges
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Read user input inside a loop
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answered Jul 30 '11 at 13:42
dankdank
1,13411 gold badge77 silver badges22 bronze badges
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How do I add the contents of an iterable to a set?
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231
You can add elements of a list to a set like this:
>>> foo = set(range(0, 4))
>>...
Pass a data.frame column name to a function
... just use the column name directly:
df <- data.frame(A=1:10, B=2:11, C=3:12)
fun1 <- function(x, column){
max(x[,column])
}
fun1(df, "B")
fun1(df, c("B","A"))
There's no need to use substitute, eval, etc.
You can even pass the desired function as a parameter:
fun1 <- function(x, colu...
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...
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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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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