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Apply pandas function to column to create multiple new columns?
... updating the row directly like this ended up being surprisingly slow - an order of magnitude slower than the apply with 'expand' + pd.concat solutions
– Dmytro Bugayev
Jun 30 at 17:33
...
Could not load file or assembly 'System.Web.Http 4.0.0 after update from 2012 to 2013
... Be sure to add the needed update to any dependent projects such as tests, etc.
– DeeArgee
Feb 9 '15 at 15:40
I did th...
Is it possible to serialize and deserialize a class in C++?
...s to me that boost::serialization requires the caller to keep track of the order in which objects are written and read. Is that correct? So if there is a change in the order in which two fields are written between versions of a program then we have an incompatibility. Is this right?
...
EF Migrations: Rollback last applied migration?
...value. Likewise, if you have applied migrations A, B, C, D, and E (in that order), then the ordinal 1 should refer to A, ordinal 2 should refer to B, and so on. So to rollback to B you could use either:
Update-Database -TargetMigration:"B"
or
Update-Database -TargetMigration:2
Edit October 201...
Difference between FOR and AFTER triggers?
...t, and fires before and instead of the insert and can be used on views, in order to insert the appropriate values into the underlying tables.
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Node.js throws “btoa is not defined” error
...rs (i.e. if you plan to exchange base64 between Node.js and a browser). In order to make it work you have to mark the input text as 'binary'.
Buffer.from('Hélló wórld!!', 'binary').toString('base64')
This gives you SOlsbPMgd/NybGQhIQ==. If you make atob('SOlsbPMgd/NybGQhIQ==') in a browser it...
What is an SSTable?
...
"An SSTable provides a persistent,ordered immutable map from keys to values, where both keys and values are arbitrary byte strings. Operations are provided to look up the value associated with a specified key, and to iterate over all key/value pairs in a spec...
How to implement classic sorting algorithms in modern C++?
...tialization {} instead of the good old parenthesized initialization () (in order to side-step all most-vexing-parse issues in generic code).
Scott Meyers's "Prefer alias declarations to typedefs". For templates this is a must anyway, and using it everywhere instead of typedef saves time and adds con...
Rotating a two-dimensional array in Python
...breakdown:
[::-1] - makes a shallow copy of the original list in reverse order. Could also use reversed() which would produce a reverse iterator over the list rather than actually copying the list (more memory efficient).
* - makes each sublist in the original list a separate argument to zip() (i....
What is an abstract class in PHP?
...declared abstract.
Note: Traits support the use of abstract methods in order to impose requirements upon the exhibiting class.
Example below :
class Non_Abstract_Class
{
abstract protected function getValue();
public function printOut() {
echo "Hello how are you?";
}
}
$...