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Group by multiple columns in dplyr, using string vector input
...e so:
data = data.frame(
asihckhdoydkhxiydfgfTgdsx = sample(LETTERS[1:3], 100, replace=TRUE),
a30mvxigxkghc5cdsvxvyv0ja = sample(LETTERS[1:3], 100, replace=TRUE),
value = rnorm(100)
)
# get the columns we want to average within
columns = names(data)[-3]
library(dplyr)
df1 <- data %...
How to check iOS version?
I want to check if the iOS version of the device is greater than 3.1.3
I tried things like:
37 Answers
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Common elements in two lists
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163
Use Collection#retainAll().
listA.retainAll(listB);
// listA now contains only the elements whi...
How does Django's Meta class work?
...:55
Moon
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answered Apr 27 '12 at 3:04
TadeckTadeck
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How to know if two arrays have the same values
...
23 Answers
23
Active
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How to distinguish between left and right mouse click with jQuery
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As of jQuery version 1.1.3, event.which normalizes event.keyCode and event.charCode so you don't have to worry about browser compatibility issues. Documentation on event.which
event.which will give 1, 2 or 3 for left, middle and right mouse buttons ...
How to shift a column in Pandas DataFrame
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In [18]: a
Out[18]:
x1 x2
0 0 5
1 1 6
2 2 7
3 3 8
4 4 9
In [19]: a.x2 = a.x2.shift(1)
In [20]: a
Out[20]:
x1 x2
0 0 NaN
1 1 5
2 2 6
3 3 7
4 4 8
share
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From inside of a Docker container, how do I connect to the localhost of the machine?
...
30 Answers
30
Active
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Class 'DOMDocument' not found
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318
You need to install the DOM extension. You can do so on Debian / Ubuntu using:
sudo apt-get in...
Pip freeze vs. pip list
... be in a specific format for pip to understand, which is
feedparser==5.1.3
wsgiref==0.1.2
django==1.4.2
...
That is the "requirements format".
Here, django==1.4.2 implies install django version 1.4.2 (even though the latest is 1.6.x).
If you do not specify ==1.4.2, the latest version available ...