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efficient circular buffer?
...in xrange(20):
... d.append(i)
...
>>> d
deque([10, 11, 12, 13, 14, 15, 16, 17, 18, 19], maxlen=10)
There is a recipe in the docs for deque that is similar to what you want. My assertion that it's the most efficient rests entirely on the fact that it's implemented in C by an incredib...
Extract a dplyr tbl column as a vector
...s2 %>% pull(5)
Resulting in...
[1] 21.0 21.0 22.8 21.4 18.7 18.1 14.3 24.4 22.8 19.2 17.8 16.4 17.3 15.2 10.4 10.4 14.7 32.4 30.4 33.9 21.5 15.5 15.2 13.3 19.2 27.3 26.0 30.4 15.8 19.7 15.0 21.4
And it also works fine with data frames:
> mtcars %>% pull(5)
[1] 3.90 3.90 3.85 3.08 3....
What does 'synchronized' mean?
...
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edited Mar 30 '18 at 7:18
Paolo Forgia
5,49477 gold badges3434 silver badges5555 bronze badges
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Where is Maven' settings.xml located on mac os?
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133
If you use brew to install maven, then the settings file should be in
/usr/local/Cellar/maven/...
Installing Ruby Gem in Windows
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73
I recommend you just use rubyinstaller
It is recommended by the official Ruby page - see https:...
Can you delete multiple branches in one command with Git?
...lean up my local repository, which has a ton of old branches: for example 3.2 , 3.2.1 , 3.2.2 , etc.
29 Answers
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Iterate a list with indexes in Python
...ld swear I've seen the function (or method) that takes a list, like this [3, 7, 19] and makes it into iterable list of tuples, like so: [(0,3), (1,7), (2,19)] to use it instead of:
...
How to find third or nth maximum salary from salary table?
...
83
Use ROW_NUMBER(if you want a single) or DENSE_RANK(for all related rows):
WITH CTE AS
(
SEL...
Is there an equivalent for the Zip function in Clojure Core or Contrib?
...
(map vector '(1 2 3) '(4 5 6))
does what you want:
=> ([1 4] [2 5] [3 6])
Haskell needs a collection of zipWith (zipWith3, zipWith4, ...) functions, because they all need to be of a specific type; in particular, the number of input lis...