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List of installed gems?
... >> Platform 0.4.0
# >> abstract 1.0.0
# >> actionmailer 3.0.5
# >> actionpack 3.0.5
# >> activemodel 3.0.5
# >> activerecord 3.0.5
Here's an updated way to get a list:
require 'rubygems'
def local_gems
Gem::Specification.sort_by{ |g| [g.name.downcase, g....
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...
in_array multiple values
...
answered Sep 24 '11 at 23:51
Mark ElliotMark Elliot
65.9k1818 gold badges132132 silver badges155155 bronze badges
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How do I install Python OpenCV through Conda?
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edited Jun 30 '17 at 10:00
Quanlong
18.4k88 gold badges5858 silver badges7474 bronze badges
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What exactly does += do in python?
...r
return self.num
>>> a = Adder(2)
>>> a += 3
in __iadd__ 3
>>> a
5
Hope this helps.
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Remove all values within one list from another list? [duplicate]
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>>> a = range(1, 10)
>>> [x for x in a if x not in [2, 3, 7]]
[1, 4, 5, 6, 8, 9]
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Cartesian product of x and y array points into single array of 2D points
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13 Answers
13
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What does the tilde (~) mean in my composer.json file?
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3 Answers
3
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Sublime Text 3 how to change the font size of the file sidebar?
... editor does not change at all. Is there anything different in sublime text3？
13 Answers
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Efficient way to rotate a list in python
...method.
from collections import deque
items = deque([1, 2])
items.append(3) # deque == [1, 2, 3]
items.rotate(1) # The deque is now: [3, 1, 2]
items.rotate(-1) # Returns deque to original state: [1, 2, 3]
item = items.popleft() # deque == [2, 3]
...