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The 'json' native gem requires installed build tools
I have ruby 1.9.2p180 (2011-02-18) [i386-mingw32] installed on my windows 7 machine. Now I tried to install the JSON gem using the command, "gem install json" and got the following error.
...
How can I filter lines on load in Pandas read_csv function?
...ec]:
filtered = df[(df['timestamp'] > targettime)]
This is selecting all rows in df (assuming df is any DataFrame, such as the result of a read_csv call, that at least contains a datetime column timestamp) for which the values in the timestamp column are greater than the value of targettime. S...
How do I pass a unique_ptr argument to a constructor or a function?
...e_ptr<Base> n)
: next(std::move(n)) {}
In order for the user to call this, they must do one of the following:
Base newBase(std::move(nextBase));
Base fromTemp(std::unique_ptr<Base>(new Base(...));
To take a unique pointer by value means that you are transferring ownership of the p...
How to delete all files and folders in a directory?
Using C#, how can I delete all files and folders from a directory, but still keep the root directory?
29 Answers
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What do single quotes do in C++ when used on multiple characters?
... answered Sep 18 '11 at 6:45
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COALESCE Function in TSQL
...not sure why you think the documentation is vague.
It simply goes through all the parameters one by one, and returns the first that is NOT NULL.
COALESCE(NULL, NULL, NULL, 1, 2, 3)
=> 1
COALESCE(1, 2, 3, 4, 5, NULL)
=> 1
COALESCE(NULL, NULL, NULL, 3, 2, NULL)
=> 3
COALESCE(6, 5, 4, ...
UnicodeDecodeError when redirecting to file
...n byte chunks. The necessary process that converts characters to bytes is called encoding. Thus, a computer requires an encoding in order to represent characters. Any text present on your computer is encoded (until it is displayed), whether it be sent to a terminal (which expects characters encode...
How do I change db schema to dbo
...rted a bunch of tables from an old sql server (2000) to my 2008 database. All the imported tables are prefixed with my username, for example: jonathan.MovieData . In the table properties it lists jonathan as the db schema. When I write stored procedures I now have to include jonathan. in f...
what is the difference between sendStickyBroadcast and sendBroadcast in Android
... return value of
registerReceiver(BroadcastReceiver,
IntentFilter). In all other ways, this
behaves the same as
sendBroadcast(Intent).
One example of a sticky broadcast sent via the operating system is ACTION_BATTERY_CHANGED. When you call registerReceiver() for that action -- even with a ...
How is attr_accessible used in Rails 4?
... away from fat model, thin controller, etc, and towards thin models, and really bloated controllers. You have to write all this stuff for every instance, it doesn't read nicely, and nesting seems to be a pain. The old attr_accessible/attr_accessor in the model system wasn't broken, and didn't need...