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dplyr: “Error in n(): function should not be called directly”
...yr first
– hadley
Apr 10 '14 at 23:58
16
As @User1257894 says, use summarize with the package, so...
What is the difference between isinstance('aaa', basestring) and isinstance('aaa', str)?
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389
In Python versions prior to 3.0 there are two kinds of strings "plain strings" and "unicode str...
How to add a new row to an empty numpy array
...2,3*i+3])
.....: l = np.asarray(l)
.....:
1000 loops, best of 3: 1.18 ms per loop
In [211]: %%timeit
.....: a = np.empty((0,3), int)
.....: for i in xrange(1000):
.....: a = np.append(a, 3*i+np.array([[1,2,3]]), 0)
.....:
100 loops, best of 3: 18.5 ms per loop
In [214]: np....
How do I unset an element in an array in javascript?
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answered Aug 28 '09 at 5:08
goinggoing
8,47922 gold badges3333 silver badges3636 bronze badges
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How to download Xcode DMG or XIP file?
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9.3.1
9.2 (Last version supporting macOS 10.12.6 Sierra)
9.1
9.0.1
Xcode 8
8.3.3
8.2.1 (Last version supporting OS X 10.11.5 El Capitan)
8.1
8.0
Xcode 7
7.3.1
7.2.1 (Last version supporting OS X 10.10 Yosemite)
7.1.1
7.0.1
Xcode 6
6.4
6.3.2
6.2 (Last version supporting OS X 10.9.5 Mavericks)
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{version} wildcard in MVC4 Bundle
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178
The -{version} basically maps to a version regex, or to be precise: (\d+(?:\.\d+){1,3}).
Using *...
Javascript - sort array based on another array
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78
Something like:
items = [
['Anne', 'a'],
['Bob', 'b'],
['Henry', 'b'],
['Andre...
C char array initialization
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edited Jan 20 '15 at 18:53
answered Sep 8 '13 at 21:51
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Diff two tabs in Vim
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189
I suggest opening the second file in the same tab instead of a new one.
Here's what I usually ...
Difference between Activity and FragmentActivity
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Alex LockwoodAlex Lockwood
80.3k3636 gold badges196196 silver badges242242 bronze badges
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