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How do I replace NA values with zeros in an R dataframe?
... mutate(myCol1 = if_else(is.na(myCol1), 0, myCol1))
Note: This works per selected column, if we need to do this for all column, see @reidjax's answer using mutate_each.
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Advantage of creating a generic repository vs. specific repository for each object?
...se GetById(int id)? How would composite keys work? I wondered if a generic selection by ID was a worthwhile abstraction. If not, what else would generic repositories be forced to express akwardly? That was the line of reasoning behind abstracting the implementation, not the interface.
...
Entity Framework and Connection Pooling
...ies and store them at once. This is called Unit of Work pattern. You can't selectively say which modified attached entity you want to save.
Combine these two patterns and you will see some interesting effects. You have only one instance of entity for the whole application. Any changes to the entity...
Is Using .NET 4.0 Tuples in my C# Code a Poor Design Decision?
...pport for tuples in C#:
private var GetDesserts()
{
return _icecreams.Select(
i => new { icecream = i, topping = new Topping(i) }
);
}
public void Eat()
{
foreach (var dessert in GetDesserts())
{
dessert.icecream.AddTopping(dessert.topping);
dessert.Eat()...
How to use Elasticsearch with MongoDB?
...ng bumped up when you update.
echo "mongodb-10gen hold" | sudo dpkg --set-selections
Start the MongoDB service.
sudo service mongodb start
Your database files default to /var/lib/mongo and your log files to /var/log/mongo.
Create a database through the mongo shell and push some dummy data int...
What is the difference between properties and attributes in HTML?
...in only one kind of value in the DOM, while some attributes (e.g. checked, selected) to retain two values; that is, the value "when it was loaded" and the value of the "dynamic state". (Isn't the DOM supposed to be to represent the state of the document to its full extent?)
It is absolutely essenti...
How fast is D compared to C++?
...out printing code and replaced writefln with writeln
Changed imports to be selective
Used pow operator (^^) instead of manual multiplication for final step of calculating average
Removed the size_type and replaced appropriately with the new index_type alias
...thus resulting in scalar2.cpp (pasteb...
initializer_list and move semantics
... std::forward<Ts>(ts)... };
}
};
//
// delegation function which selects the correct maker
//
template<class Array, class...Ts>
auto make(Ts&&...ts)
{
auto m = maker<Array>();
return m(std::forward<Ts>(ts)...);
}
// vectors and arrays of non-copyable types
us...
What are the main uses of yield(), and how does it differ from join() and interrupt()?
... calling yield(), there's still no guarantee that the same thread won't be selected for execution again, given a pool of equal priority threads.
– Andrew Fielden
Aug 8 '11 at 9:20
...
What is the smallest possible valid PDF?
... This will not work, you need to define a font resource and select it inside the page content for the text to show up.
– yms
Aug 21 '15 at 20:36
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