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Adding new column to existing DataFrame in Python pandas
... because if you have multiple rows, and you use the assignment, it assigns all rows of the new column with that value ( in your case e) which is usually undesirable.
– Paniz
Apr 27 '19 at 22:42
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Is there a way for multiple processes to share a listening socket?
...POSIX type OS), using fork() will cause the forked child to have copies of all the parent's file descriptors. Any that it does not close will continue to be shared, and (for example with a TCP listening socket) can be used to accept() new sockets for clients. This is how many servers, including Apac...
Django: How to manage development and production settings?
...s you define environment variables in an "environment" (.env) file.
Finally, note that you can take advantage of the PYTHONPATH variable to store the settings in a completely different location (e.g. on a production server, storing them in /etc/). This allows for separating configuration from ap...
Combining two expressions (Expression)
...m);
}
Starting from .NET 4.0, there is the ExpressionVisitor class which allows you to build expressions that are EF safe.
public static Expression<Func<T, bool>> AndAlso<T>(
this Expression<Func<T, bool>> expr1,
Expression<Func<T, bool>&...
system(“pause”); - Why is it wrong?
...upon because it's a platform-specific hack that has nothing to do with actually learning programming, but instead to get around a feature of the IDE/OS - the console window launched from Visual Studio closes when the program has finished execution, and so the new user doesn't get to see the output o...
One SVN repository or many?
... its own tags, trunk and branches. If one gets too big or I need to physically isolate a customer's code for their comfort, I can quickly and easily create a new repository.
I recently consulted with a relatively large firm on migrating multiple source code control systems to Subversion. They have...
One-liner to recursively list directories in Ruby?
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Dir.glob("**/*/") # for directories
Dir.glob("**/*") # for all files
Instead of Dir.glob(foo) you can also write Dir[foo] (however Dir.glob can also take a block, in which case it will yield each path instead of creating an array).
Ruby Glob Docs
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How to know if two arrays have the same values
..., i.e. ['a', 'b'] and ['a,b']. I would only recommend this technique for small throwaway scripts.
– alex
Mar 7 '16 at 16:23
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How to make a python, command-line program autocomplete arbitrary things NOT interpreter
...ts, i.e. --help, --verbose and --version. For your purposes, you'll essentially want to customise the values that are put into opts.
Do have a look at the example on the linked page, it's all pretty straightforward.
share
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What's the cleanest way of applying map() to a dictionary in Swift?
I'd like to map a function on all keys in the dictionary. I was hoping something like the following would work, but filter cannot be applied to dictionary directly. What's the cleanest way of achieving this?
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