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Append an object to a list in R in amortized constant time, O(1)?
...irthday. Some kind readers keep repeating any shortcomings with it, so by all means also see some of the comments below. One suggestion for list types:
newlist <- list(oldlist, list(someobj))
In general, R types can make it hard to have one and just one idiom for all types and uses.
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What is the best project structure for a Python application? [closed]
...l architecture of your application.
/foo
/bar
/baz
I recommend putting all of this under the "name-of-my-product" directory. So, if you're writing an application named quux, the directory that contains all this stuff is named /quux.
Another project's PYTHONPATH, then, can include /path/to/quu...
Django: How to completely uninstall a Django app?
What is the procedure for completely uninstalling a Django app, complete with database removal?
5 Answers
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How do you generate dynamic (parameterized) unit tests in python?
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This is called "parametrization".
There are several tools that support this approach. E.g.:
pytest's decorator
parameterized
The resulting code looks like this:
from parameterized import parameterized
class TestSequence(unittes...
What does $_ mean in PowerShell?
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This is the variable for the current value in the pipe line, which is called $PSItem in Powershell 3 and newer.
1,2,3 | %{ write-host $_ }
or
1,2,3 | %{ write-host $PSItem }
For example in the above code the %{} block is called for every value in the array. The $_ or $PSItem variable ...
Correct owner/group/permissions for Apache 2 site files/folders under Mac OS X?
...go-rwx DIR (nobody other than owner can access content)
chmod go+x DIR (to allow "users" including _www to "enter" the dir)
sudo chgrp -R _www ~/my/web/root (all web content is now group _www)
chmod -R go-rwx ~/my/web/root (nobody other than owner can access web content)
chmod -R g+rx ~/my/web/root...
How many GCC optimization levels are there?
..., the default if no optimization level is specified)
-O1 (optimize minimally)
-O2 (optimize more)
-O3 (optimize even more)
-Ofast (optimize very aggressively to the point of breaking standard compliance)
-Og (Optimize debugging experience. -Og enables optimizations that do not interfere...
How can I handle time zones in my webapp?
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The majority of your users probably will not change timezones much, or at all. For the most part, the situation you outlined is uncommon. By implementing a dropdown with a suitable default, you should be able to make things easy enough for those who do move around (because they typically have a bet...
Importing from builtin library when module with same name exists
Situation:
- There is a module in my project_folder called calendar
- I would like to use the built-in Calendar class from the Python libraries
- When I use from calendar import Calendar it complains because it's trying to load from my module.
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Abstract classes in Swift Language
... importantly, notice that there is no dynamic dispatch. When logSalary is called on the instance that is stored as a SoftwareEngineer it calls the overridden version of the method. When logSalary is called on the instance after it has been cast to an Employee, it calls the original implementation (i...