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How do I add files without dots in them (all extension-less files) to the gitignore file?
... Note: to work with other exclusion rules, this will need to be the first set of rules in your .gitignore file
– Erik
Jan 12 '15 at 22:41
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Python Dictionary Comprehension
...(5)}
>>> print d
{0: 0, 1: 1, 2: 4, 3: 9, 4: 16}
If you want to set them all to True:
>>> d = {n: True for n in range(5)}
>>> print d
{0: True, 1: True, 2: True, 3: True, 4: True}
What you seem to be asking for is a way to set multiple keys at once on an existing dict...
What does -> mean in Python function definitions?
...tly noticed something interesting when looking at Python 3.3 grammar specification :
7 Answers
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Is the Scala 2.8 collections library a case of “the longest suicide note in history”? [closed]
... pretty advanced. Consider this:
scala> import collection.immutable.BitSet
import collection.immutable.BitSet
scala> val bits = BitSet(1, 2, 3)
bits: scala.collection.immutable.BitSet = BitSet(1, 2, 3)
scala> val shifted = bits map { _ + 1 }
shifted: scala.collection.immutable.BitSet = B...
How to open, read, and write from serial port in C?
...om tcgetattr. You cannot zero-out a struct termios, configure it, and then set the tty with tcsetattr. If you use the zero-out method, then you will experience unexplained intermittent failures, especially on the BSDs and OS X. "Unexplained intermittent failures" include hanging in read(3).
#includ...
Integer.toString(int i) vs String.valueOf(int i)
I am wondering why the method String.valueOf(int i) exists ? I am using this method to convert int into String and just discovered the Integer.toString(int i) method.
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How to read data when some numbers contain commas as thousand separator?
...First create a new class definition, then create a conversion function and set it as an "as" method using the setAs function like so:
setClass("num.with.commas")
setAs("character", "num.with.commas",
function(from) as.numeric(gsub(",", "", from) ) )
Then run read.csv like:
DF <- read...
What guarantees are there on the run-time complexity (Big-O) of LINQ methods?
...on is O(1) instead of O(N).
Distinct, GroupBy Join, and I believe also the set-aggregation methods (Union, Intersect and Except) use hashing, so they should be close to O(N) instead of O(N²).
Contains checks for an ICollection implementation, so it may be O(1) if the underlying collection is also O...
Finding all possible combinations of numbers to reach a given sum
...d you go about testing all possible combinations of additions from a given set N of numbers so they add up to a given final number?
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LINQ with groupby and count
This is pretty simple but I'm at a loss:
Given this type of data set:
3 Answers
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