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Why isn't `int pow(int base, int exponent)` in the standard C++ libraries?
...nity cost). If all that stuff was added, the next standard C++ would be C++215x and would probably be fully implemented by compiler developers three hundred years after that.
Anyway, that's my (rather voluminous) thoughts on the matter. If only votes were handed out bases on quantity rather than qu...
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:
...
Equation (expression) parser with precedence?
...
22 Answers
22
Active
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Saving an Object (Data persistence)
...40)
pickle.dump(company1, output, pickle.HIGHEST_PROTOCOL)
company2 = Company('spam', 42)
pickle.dump(company2, output, pickle.HIGHEST_PROTOCOL)
del company1
del company2
with open('company_data.pkl', 'rb') as input:
company1 = pickle.load(input)
print(company1.name) # -> ...
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...
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...
Show pending migrations in rails
...
261
rake db:migrate:status (Rails 3 to 5) or rails db:migrate:status (Rails 5) will accomplish thi...
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...
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...