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Why shouldn't I use PyPy over CPython if PyPy is 6.3 times faster?
...to mention, has tenuous support for C extensions. It has support, but typically at slower-than-Python speeds and it's iffy at best. Hence a lot of modules simply require CPython. PyPy doesn't support numpy PyPy now supports numpy. Some extensions are still not supported (Pandas, SciPy, etc.), take a...
Logical operators for boolean indexing in Pandas
...Error: The truth value of an array is ambiguous. Use a.empty, a.any() or a.all().
when used as a boolean value. That's because its unclear when it should be True or False. Some users might assume they are True if they have non-zero length, like a Python list. Others might desire for it to be True ...
What does “program to interfaces, not implementations” mean?
...t worried about implementation and the interface signature determines what all operations can be done. This can be used to change the behavior of a program at run-time. It also helps you to write far better programs from the maintenance point of view.
Here's a basic example for you.
public enum La...
How to validate an email address in PHP
...($email, FILTER_VALIDATE_EMAIL)) {
// invalid emailaddress
}
Additionally you can check whether the domain defines an MX record:
if (!checkdnsrr($domain, 'MX')) {
// domain is not valid
}
But this still doesn't guarantee that the mail exists. The only way to find that out is by sending ...
Can you determine if Chrome is in incognito mode via a script?
...his, or the accepted answer should change. Not to take away from the originally accepted answer as it was the correct solution at the time.
– Cruncher
Aug 12 '19 at 15:13
1
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What are all the common undefined behaviours that a C++ programmer should know about? [closed]
What are all the common undefined behaviours that a C++ programmer should know about?
11 Answers
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Need to list all triggers in SQL Server database with table name and table's schema
I need to list all triggers in SQL Server database with table name and table's schema.
19 Answers
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Returning IEnumerable vs. IQueryable
...ecution.
The difference is that IQueryable<T> is the interface that allows LINQ-to-SQL (LINQ.-to-anything really) to work. So if you further refine your query on an IQueryable<T>, that query will be executed in the database, if possible.
For the IEnumerable<T> case, it will be L...
Repository Pattern Step by Step Explanation [closed]
...a summary, I would describe the wider impact of the repository pattern. It allows all of your code to use objects without having to know how the objects are persisted. All of the knowledge of persistence, including mapping from tables to objects, is safely contained in the repository.
Very often, y...
Getting the IP address of the current machine using Java
... has the following effect: it sets the destination for Send/Recv, discards all packets from other addresses, and - which is what we use - transfers the socket into "connected" state, settings its appropriate fields. This includes checking the existence of the route to the destination according to th...