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What does {0} mean when initializing an object?
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What's happening here is called aggregate initialization. Here is the (abbreviated) definition of an aggregate from section 8.5.1 of the ISO spec:
An aggregate is an array or a class with no user-declared constructors, no private or protected non...
How to change default timezone for Active Record in Rails?
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I have decided to compile this answer because all others seem to be incomplete.
config.active_record.default_timezone determines whether to use Time.local (if set to :local) or Time.utc (if set to :utc) when pulling dates and times from the database. The default is :...
Are there disadvantages to using a generic varchar(255) for all text-based fields?
...stcode , first name , last name , town , country , phone number etc, all of which are defined as VARCHAR(255) even though none of these fields will ever come close to having 255 characters. (If you're wondering, it's this way because Ruby on Rails migrations map String fields to VARCHAR(25...
Aggregate / summarize multiple variables per group (e.g. sum, mean)
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what if I instead of x1 and x2 I want to use all the remaining variables (other than year, month)
– Clock Slave
Mar 16 '16 at 11:22
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Static Classes In Java
...ion by client code as it makes no sense to instantiate a static class
Make all the members and functions of the class static - Since the class cannot be instantiated no instance methods can be called or instance fields accessed
Note that the compiler will not prevent you from declaring an instance ...
How to set a single, main title above all the subplots with Pyplot?
...m using pyplot . I have 4 subplots. How to set a single, main title above all the subplots? title() sets it above the last subplot.
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recursively add file extension to all files
...rectories containing files with no file extension. I want to add .jpg to all the files contained within these directories. I've seen bash scripts for changing the file extension but not for just adding one. It also needs to be recursive, can someone help please?
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How to call an external command?
How do you call an external command (as if I'd typed it at the Unix shell or Windows command prompt) from within a Python script?
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MongoDB or CouchDB - fit for production? [closed]
...re is a list of other people using Couch: CouchDB in the wild
The major challenge is to know how to organize your documents and stop thinking in terms of relational data.
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Hide all warnings in ipython
...t of an ipython session, and to avoid confusing viewers, I want to disable all warnings emitted by warnings.warn calls from different packages. Is there a way to configure the ipythonrc file to automatically disable all such warnings?
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