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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...
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...
Equation (expression) parser with precedence?
...
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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) # -> ...
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...
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 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...
Count number of records returned by group by
... COUNT(*) OVER () AS TotalRecords
from temptable
group by column_1, column_2, column_3, column_4
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How to reshape data from long to wide format
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268
Using reshape function:
reshape(dat1, idvar = "name", timevar = "numbers", direction = "wide"...
Some built-in to pad a list in python
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oyvind
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answered Aug 9 '10 at 9:43
John La RooyJohn La ...