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Relative frequencies / proportions with dplyr
...
Try this:
mtcars %>%
group_by(am, gear) %>%
summarise(n = n()) %>%
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 vigne...
Creating and playing a sound in swift
...member to run it this way do { (player object) } catch _ { } or your will get a bug! :)
– ParisNakitaKejser
Jun 26 '15 at 20:02
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How to create default value for function argument in Clojure
...ach is you can assign the default function a different name (decimal, hex, etc) which may be more descriptive and/or a different scope (var, local). The partial function can also be mixed with some of the approaches above if desired:
(defn string->integer
([s] (string->integer s 10))
([b...
XML serialization in Java? [closed]
...t's right, JAXB is definitely the best option!
– ivan_ivanovich_ivanoff
Apr 9 '09 at 16:55
1
JAXB...
Difference between Lookup() and Dictionary(Of list())
...alue>, which means that it's efficient to use with Count(), ElementAt() etc.
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Does a finally block always run?
...led. Is there a catch that I am missing? download.oracle.com/docs/cd/E17476_01/javase/1.5.0/docs/guide/…
– spurserh
Jul 18 '10 at 14:40
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How can I check if a file exists in Perl?
...mething exists at given path using the -e file-test operator.
print "$base_path exists!\n" if -e $base_path;
However, this test is probably broader than you intend. The code above will generate output if a plain file exists at that path, but it will also fire for a directory, a named pipe, a syml...
How to sort Map values by key in Java?
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@cricket_007 the code is demonstrating specifically how to iterate across they keys for a map that isn't already sorted.
– Jherico
Mar 2 '16 at 17:47
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How do I extend a class with c# extension methods?
...Check the full example here
http://www.dotnetreaders.com/articles/Extension_methods_in_C-sharp.net,Methods_in_C_-sharp/201
Example:
class Extension
{
static void Main(string[] args)
{
string s = "sudhakar";
Console.WriteLine(s.GetWordCount());
...
Hash String via SHA-256 in Java
...e this to UTF-16 if needed
md.update(text.getBytes(StandardCharsets.UTF_8));
byte[] digest = md.digest();
String hex = String.format("%064x", new BigInteger(1, digest));
System.out.println(hex);
}
}
In the snippet above, digest contains the hashed string and hex contains a hexad...