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What are the advantages of NumPy over regular Python lists?
...pointers which double in size) -- a much costlier piece of hardware!
The difference is mostly due to "indirectness" -- a Python list is an array of pointers to Python objects, at least 4 bytes per pointer plus 16 bytes for even the smallest Python object (4 for type pointer, 4 for reference count, ...
Why extend the Android Application class?
...ither preferable to another approach or necessary to accomplish something. If you have an expensive, frequently used object you can initialize it in an IntentService when you detect that the object isn't currently present. Application itself runs on the UI thread, while IntentService runs on its own...
How to create a template function within a class? (C++)
...hem, but you cannot partially specialize them. Unfortunately I don't know if this is a compiler-specific extension, or C++ standard.
– Patrick Johnmeyer
Jun 10 '09 at 1:14
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How should you build your database from source control?
... Do NOT copy data between the environments
How do you deal with potential differences between test and production environments in deployment scripts?
Use templates, so that actually you would produce different set of scripts for each environment (ex. references to external systems, linked databases,...
Delete all local git branches
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The 'git branch -d' subcommand can delete more than one branch. So, simplifying @sblom's answer but adding a critical xargs:
git branch -D `git branch --merged | grep -v \* | xargs`
or, further simplified to:
git branch --merged | grep -v \* | xargs git branch -D
Importantly, as noted by @A...
What is the Comonad typeclass in Haskell?
...ng with a comonad".
Sequences, streams, and segments
Comonads in everyday life
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How does Rails keep track of which migrations have run for a database?
...ile name and inserts a row for that "version", indicating it has been run. If you roll back that migration, Rails will delete the corresponding row from schema_migrations.
For example, running a migration file named 20120620193144_create_users.rb will insert a new row with a version of 201206201931...
Copying files from Docker container to host
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Here's a handy way to get at your latest container if you're simply using docker for a temp Linux environment: docker ps -alq.
– Josh Habdas
Jun 3 '15 at 15:29
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Clearing coverage highlighting in Eclipse
...ghts. Sadly eCobertura plugins seems to be not maintained anymore. However if you start writing into the class, its gone. So type a space, and then undo, and its gone.
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Change a Django form field to a hidden field
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If you have a custom template and view you may exclude the field and use {{ modelform.instance.field }} to get the value.
also you may prefer to use in the view:
form.fields['field_name'].widget = forms.HiddenInput()
but...