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Sum a list of numbers in Python
... element 1) / 2, (element 1 + element 2) / 2, ... etc.
We make two lists: one of every element except the first, and one of every element except the last. Then the averages we want are the averages of each pair taken from the two lists. We use zip to take pairs from two lists.
I assume you want to...
Creating an instance using the class name and calling constructor
...fy it pretty easily.
Note that the class name has to be a fully-qualified one, i.e. including the namespace. For nested classes, you need to use a dollar (as that's what the compiler uses). For example:
package foo;
public class Outer
{
public static class Nested {}
}
To obtain the Class ob...
What is the colon operator in Ruby?
...
Just to demonstrate some of the things mentioned in the answers:
require 'benchmark'
n = 1_000_000
print '"foo".equal? "foo" -> ', ("foo".equal? "foo"), "\n"
print '"foo" == "foo" -> ', ("foo" == "foo" ), "\n"
print ':foo.equal? :foo -> ', (:foo.eq...
How to convert QString to std::string?
...
One of the things you should remember when converting QString to std::string is the fact that QString is UTF-16 encoded while std::string... May have any encodings.
So the best would be either:
QString qs;
// Either this i...
PHP 5.4 Call-time pass-by-reference - Easy fix available?
... on a function call - only on function definitions. Function definitions alone are enough to correctly pass the argument by reference. As of PHP 5.3.0, you will get a warning saying that "call-time pass-by-reference" is deprecated when you use & in foo(&$a);.
For example, instead of using:...
Return first N key:value pairs from dict
...s a list"
return list(islice(iterable, n))
See it working online: ideone
Update for Python 3.6
n_items = take(n, d.items())
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Regular Expression to get a string between parentheses in Javascript
...
\( : match an opening parentheses
( : begin capturing group
[^)]+: match one or more non ) characters
) : end capturing group
\) : match closing parentheses
Here is a visual explanation on RegExplained
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How to find index of all occurrences of element in array?
...UPDATE: As per VisioN's comment, a simple for loop would get the same job done more efficiently, and it is easier to understand and therefore easier to maintain:
function getAllIndexes(arr, val) {
var indexes = [], i;
for(i = 0; i < arr.length; i++)
if (arr[i] === val)
...
Quickly reading very large tables as dataframes
...e RODBC package, and the reverse depends section of the DBI package page. MonetDB.R gives you a data type that pretends to be a data frame but is really a MonetDB underneath, increasing performance. Import data with its monetdb.read.csv function. dplyr allows you to work directly with data stored ...
bundle install fails with SSL certificate verification error
...
Update
Now that I've karma wh..err mined enough from this answer everyone should know that this should have been fixed.
re: via Ownatik again bundle install fails with SSL certificate verification error
gem update --system
My answer is still correct and left below for reference if that ends...