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Not class selector in jQuery
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answered Jan 6 '11 at 10:53
lonesomedaylonesomeday
207k4545 gold badges296296 silver badges306306 bronze badges
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How to convert a data frame column to numeric type?
...ac num
1 a 1 1 a 1
2 b 2 2 b 2
3 c 3 3 c 3
4 d 4 4 d 4
5 e 5 5 e 5
and let us run:
> sapply(d, mode)
char fake_char fac char_fac num
"character" "character...
Entity Framework Join 3 Tables
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answered Jan 10 '14 at 18:30
MarcinJuraszekMarcinJuraszek
116k1313 gold badges164164 silver badges235235 bronze badges
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In git, is there a way to show untracked stashed files without applying the stash?
...ut is pretty obvious from The commit which introduced the -u feature, 787513..., and the way the rest of the documentation for git-stash phrases things... or just by doing git log --graph stash@{0})
You can view just the "untracked" portion of the stash via:
git show stash@{0}^3
or, just the "un...
how does multiplication differ for NumPy Matrix vs Array classes?
...find it more trouble than it's worth, though.
For arrays (prior to Python 3.5), use dot instead of matrixmultiply.
E.g.
import numpy as np
x = np.arange(9).reshape((3,3))
y = np.arange(3)
print np.dot(x,y)
Or in newer versions of numpy, simply use x.dot(y)
Personally, I find it much more read...
The Ruby %r{ } expression
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Matthew
30611 silver badge1818 bronze badges
answered Sep 12 '12 at 9:10
EurekaEureka
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Remove duplicated rows using dplyr
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139
Note: dplyr now contains the distinct function for this purpose.
Original answer below:
lib...
How can I specify working directory for popen
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answered Nov 6 '09 at 3:10
Mark RushakoffMark Rushakoff
214k3737 gold badges383383 silver badges383383 bronze badges
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Is a Python list guaranteed to have its elements stay in the order they are inserted in?
...nd places it behind the content of another.
If we have
list1 = [0, 1, 2, 3, 4]
list2 = [5, 6, 7, 8, 9]
Then
list1 + list2
Is the same as
[0, 1, 2, 3, 4] + [5, 6, 7, 8, 9]
Which evaluates to
[0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
Much like
"abdcde" + "fghijk"
Produces
"abdcdefghijk"
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Asynchronous shell commands
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answered Mar 3 '10 at 1:06
Carl NorumCarl Norum
195k2525 gold badges378378 silver badges444444 bronze badges
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