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What's the safest way to iterate through the keys of a Perl hash?
...eys with doubled values works fine using keys():
%h = (a => 1, b => 2);
foreach my $k (keys %h)
{
$h{uc $k} = $h{$k} * 2;
}
producing the expected resulting hash:
(a => 1, A => 2, b => 2, B => 4)
But using each() to do the same thing:
%h = (a => 1, b => 2);
keys %h...
How can I use map and receive an index as well in Scala?
...ls.zipWithIndex.foreach{ case (e, i) => println(i+" "+e) }
0 Mary
1 had
2 a
3 little
4 lamb
From: http://www.artima.com/forums/flat.jsp?forum=283&thread=243570
You also have variations like:
for((e,i) <- List("Mary", "had", "a", "little", "lamb").zipWithIndex) println(i+" "+e)
or:
...
Maven 3 warnings about build.plugins.plugin.version
...lt;artifactId>maven-compiler-plugin</artifactId>
<version>2.3.2</version>
The warning should be resolved.
Regarding this:
'build.plugins.plugin.version' for
org.apache.maven.plugins:maven-compiler-plugin is missing
Many people have mentioned why the issue is happeni...
Analyze audio using Fast Fourier Transform
...
209
The array you are showing is the Fourier Transform coefficients of the audio signal. These coe...
Reading an Excel file in python using pandas
...
229
Close: first you call ExcelFile, but then you call the .parse method and pass it the sheet nam...
How can I suppress all output from a command using Bash?
...rk in all shells):
scriptname &>/dev/null
scriptname >/dev/null 2>&1
scriptname >/dev/null 2>/dev/null
And, if you want to record the messages, but not see them, replace /dev/null with an actual file, such as:
scriptname &>scriptname.out
For completeness, under Wi...
How do you use the ? : (conditional) operator in JavaScript?
...userType = "Minor";
} else {
userType = "Adult";
}
if (userIsYoungerThan21) {
serveDrink("Grape Juice");
} else {
serveDrink("Wine");
}
This can be shortened with the ?: like so:
var userType = userIsYoungerThan18 ? "Minor" : "Adult";
serveDrink(userIsYoungerThan21 ? "Grape Juice" : "Wine...
Center a column using Twitter Bootstrap 3
How do I center a div of one column size within the container (12 columns) in Twitter Bootstrap 3 ?
34 Answers
...
Show pending migrations in rails
...
261
rake db:migrate:status (Rails 3 to 5) or rails db:migrate:status (Rails 5) will accomplish thi...