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Convert column classes in data.table
...sing lapply and as.character:
dtnew <- dt[, lapply(.SD, as.character), by=ID]
str(dtnew)
Classes ‘data.table’ and 'data.frame': 10 obs. of 3 variables:
$ ID : Factor w/ 2 levels "A","B": 1 1 1 1 1 2 2 2 2 2
$ Quarter: chr "1" "2" "3" "4" ...
$ value : chr "1.487145280568" "-0.82...
How to get distinct values for non-key column fields in Laravel?
...
You should use groupby. In Query Builder you can do it this way:
$users = DB::table('users')
->select('id','name', 'email')
->groupBy('name')
->get();
...
Binding a WPF ComboBox to a custom list
...to be due to an NHibernate/WPF compatibility issue. The problem was caused by the way WPF checks for object equality. I was able to get my stuff to work by using the object ID property in the SelectedValue and SelectedValuePath properties.
<ComboBox Name="CategoryList"
DisplayMemberPat...
jQuery: more than one handler for same event
...e and w3.org/TR/2014/REC-html5-20141028/…. Event handlers can be removed by passing a reference to the handler that was registered
– Russ Cam
Aug 11 '15 at 23:26
...
Start an Activity with a parameter
...sed in the odd case where you're creating an Activity that will be started by another app (for example, one of the edit activities in a Tasker plugin) and therefore do not control the Intent which launches the Activity.
You can create a base-class Activity that has a constructor with a parameter, t...
Change bundle identifier in Xcode when submitting my first app in IOS
...
By default, Xcode sets the bundle identifier to the bundle/company identifier that you set during project creation + project name.
This is similar to what you see in the Project > Summary screen.
But you can change t...
Select top 10 records for each category
... FROM (
SELECT Field1,Field2, Rank()
over (Partition BY Section
ORDER BY RankCriteria DESC ) AS Rank
FROM table
) rs WHERE Rank <= 10
If your RankCriteria has ties then you may return more than 10 rows and Matt's solution may be better for y...
jQuery ID starts with
... imageUploader: {
brandingHtml: "Powered by \u003ca href=\"https://imgur.com/\"\u003e\u003csvg class=\"svg-icon\" width=\"50\" height=\"18\" viewBox=\"0 0 50 18\" fill=\"none\" xmlns=\"http://www.w3.org/2000/svg\"\u003e\u003cpath d=\"M46.1709 9.17788C46.1709 8.26454...
View/edit ID3 data for MP3 files
...
A bit late, but you can add the performers/artists by the following: mp3.Tag.Performers = new string[] { "Performer 1", "Performer 2", "Performer 3" };
– nokturnal
Aug 15 '11 at 20:28
...
How can I convert this foreach code to Parallel.ForEach?
...
Foreach loop:
Iterations takes place sequentially, one by one
foreach loop is run from a single Thread.
foreach loop is defined in every framework of .NET
Execution of slow processes can be slower, as they're run serially
Process 2 can't start until 1 is done. Proce...