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Relative frequencies / proportions with dplyr
...()) %>%
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 ea...
java: HashMap not working
...difference in the code. Auto-boxing means you can write:
myMap.put("foo", 3);
instead of:
myMap.put("foo", new Integer(3));
Auto-boxing means the first version is implicitly converted to the second. Auto-unboxing means you can write:
int i = myMap.get("foo");
instead of:
int i = myMap.get(...
Where does Jenkins store configuration files for the jobs it runs?
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130
Jenkins stores the configuration for each job within an eponymous directory in jobs/. The job c...
How to match “any character” in regular expression?
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answered May 26 '10 at 12:31
Delan AzabaniDelan Azabani
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How do I specify the Linq OrderBy argument dynamically?
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3
But is it true when it comes to Linq expressions interpreted by providers, like Entity Framework (sql server, or other ) ??
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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 ver...
Library not loaded: /usr/local/opt/readline/lib/libreadline.6.2.dylib
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379
I was getting the exact same error, but the above answers didn't work for me. I had to reinsta...
Overriding id on create in ActiveRecord
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13 Answers
13
Active
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How to import module when module name has a '-' dash or hyphen in it?
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edited Dec 2 '11 at 13:56
answered Dec 2 '11 at 2:00
S...
Why are data transfer objects (DTOs) an anti-pattern?
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edited Jan 25 '10 at 3:40
Jim Ferrans
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ans...