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How can I setup & run PhantomJS on Ubuntu?
...re
sudo wget https://bitbucket.org/ariya/phantomjs/downloads/phantomjs-1.9.7-linux-x86_64.tar.bz2
sudo tar xjf phantomjs-1.9.7-linux-x86_64.tar.bz2
sudo ln -s /usr/local/share/phantomjs-1.9.7-linux-x86_64/bin/phantomjs /usr/local/share/phantomjs
sudo ln -s /usr/local/share/phantomjs-1.9.7-linux-x86_...
Relative frequencies / proportions with dplyr
...t;%
mutate(freq = n / sum(n))
# am gear n freq
# 1 0 3 15 0.7894737
# 2 0 4 4 0.2105263
# 3 1 4 8 0.6153846
# 4 1 5 5 0.3846154
From the dplyr vignette:
When you group by multiple variables, each summary peels off one level of the grouping. That makes it easy to p...
Is a `=default` move constructor equivalent to a member-wise move constructor?
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answered Aug 17 '13 at 16:11
Pierre FourgeaudPierre Fourgeaud
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What is hashCode used for? Is it unique?
I notice there is a getHashCode() method in every controls, items, in WP7, which return a sequence of number. Can I use this hashcode to identify an item? For example I want to identify a picture or a song in the device, and check it whereabout. This could be done if the hashcode given for specifi...
What does f+++++++++ mean in rsync logs?
...ll also be output, but only if the receiving rsync is at least version 2.6.7 (you can use -vv with older versions of rsync, but that also turns on the output of other verbose mes-
sages).
The "%i" escape has a cryptic output that is 11 letters long. The general format is like the string YXcstpoguax...
Measuring function execution time in R
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edited Aug 24 '14 at 16:57
Pertinax
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answered Jul 23 '13 at 6:00
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Why does X[Y] join of data.tables not allow a full outer join, or a left join?
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To quote from the data.table FAQ 1.11 What is the difference between X[Y] and merge(X, Y)?
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What is the difference between “#!/usr/bin/env bash” and “#!/usr/bin/bash”?
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337
Running a command through /usr/bin/env has the benefit of looking for whatever the default versi...
Where does Scala look for implicits?
...l type, not type parameter: it is a type argument to Ordering. See section 7.2 of the Scala specification.
This is available since Scala 2.8.0.
Outer Objects for Nested Types
I haven't actually seen examples of this. I'd be grateful if someone could share one. The principle is simple:
class A(va...
How to recursively find the latest modified file in a directory?
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plundraplundra
15k33 gold badges2727 silver badges2323 bronze badges
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