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What is the purpose of “android.intent.category.DEFAULT”?
...ies, then Android will present all candidates to the user and the user can select his preferred default.
Reference:
http://developer.android.com/guide/components/intents-filters.html
Extract from that page:
Android treats all implicit intents passed tostartActivity() as if they contained at ...
When to use MongoDB or other document oriented database systems? [closed]
...cal CRUD stuff. Storing what is essentially a huge hash, and being able to select on any of those keys, is what most people use a relational database for. If your DB is 3NF and you don’t do any joins (you’re just selecting a bunch of tables and putting all the objects together, AKA what most peo...
ReadOnlyCollection or IEnumerable for exposing member collections?
...y of other options for wrapping trivially - the nice thing about Skip over Select/Where is that there's no delegate to execute pointlessly for each iteration.)
If you're not using .NET 3.5 you can write a very simple wrapper to do the same thing:
public static IEnumerable<T> Wrapper<T>...
How to join (merge) data frames (inner, outer, left, right)
...s these operations in SQL.
library(sqldf)
## inner join
df3 <- sqldf("SELECT CustomerId, Product, State
FROM df1
JOIN df2 USING(CustomerID)")
## left join (substitute 'right' for right join)
df4 <- sqldf("SELECT CustomerId, Product, State
FROM df1...
How do you fork your own repository on GitHub?
...our repo's main page on github.
Click the + icon in the top right corner.
Select "Import repository".
Where it asks for the "Old URL", paste the URL you copied at step #1
Enter the name of your new repo and click Begin Import.
That's it! You now have a copy of the full repo, with all commit histor...
Cannot create an NSPersistentStoreCoordinator with a nil model
...fore they aren't considered the same.
The quickest way to fix this, is to select the xcdatamodel file in your project navigator and in to the menu bar
Editor->Add Model Version...
and add a new version of your model. Make all changes to the new version.
This works in Xcode 5
...
Multiple aggregations of the same column using pandas GroupBy.agg()
... column names
The values are tuples whose first element is the column to select and the second element is the aggregation to apply to that column.
Pandas provides the pandas.NamedAgg namedtuple with the fields
['column', 'aggfunc'] to make it clearer what the arguments are. As
usual, the agg...
Java to Clojure rewrite
... STM transactional behaviour by wrapping any code in a (dosync ...) block.
Select the right overall web framework - Clojure has quite a few already but I'd strongly recommend Ring - see this excellent video "One Ring To Bind Them" plus either Fleet or Enlive or Hiccup depending on your templating p...
Should I use #define, enum or const?
... this type. To track the current state of a record and to create a mask to select records in certain states. Create an inline function to test if the value of the type is valid for your purpose; as a state marker vs a state mask. This will catch bugs as the typedef is just an int and a value such as...
C# DLL config file
...n.GetType() == typeof(ConnectionStringsSection)
select section).FirstOrDefault() as ConnectionStringsSection;
if (connSection != null)
{
list.AddRange(connSection.ConnectionStrings.Cast<ConfigurationElement>());
}
}
/// &l...