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data.table vs dplyr: can one do something well the other can't or does poorly?
... ## data.table syntax
left_join(DT2, DT1) ## dplyr syntax
# 2. select columns while join
DT1[DT2, .(z, i.mul)]
left_join(select(DT2, x, y, mul), select(DT1, x, y, z))
# 3. aggregate while join
DT1[DT2, .(sum(z) * i.mul), by = .EACHI]
DF1 %>% group_by(x, y) %>% summarise(z = su...
Could not load file or assembly 'System.Web.Mvc'
...
In VS2010, right click the project in the Solution Explorer and select 'Add Deployable Dependencies'. Then check the MVC related check boxes in the following dialog.
This creates a '_bin_deployableAssemblies' folder in the project which contains all the .dll files mentioned in other answ...
What exactly does git's “rebase --preserve-merges” do (and why?)
...her part. The differences with --preserve-merges concern which commits are selected for replay and how that replaying works for merge commits.
To be more explicit about the main differences between normal and merge-preserving rebase:
Merge-preserving rebase is willing to replay (some) merge commi...
Easier way to debug a Windows service
...classes.
The solution I came up with uses the Environment.Interactive the select running mode, as suggested by other answers to this post.
static void Main()
{
ServiceBase[] servicesToRun;
servicesToRun = new ServiceBase[]
{
new MyService()
};
if (Environment.UserInter...
Reloading/refreshing Kendo Grid
...he Kendo UI Grid based on some calls, that were happening on some dropdown selects. Here is what I ended up using:
$.ajax({
url: '/api/....',
data: { myIDSArray: javascriptArrayOfIDs },
traditional: true,
success: function(result) {
searchResults = result...
Where are the PostgreSQL logs on macOS?
...
Just ask your database:
SELECT
*
FROM
pg_settings
WHERE
category IN( 'Reporting and Logging / Where to Log' , 'File Locations')
ORDER BY
category,
name;
In my case, it's in "/Library/PostgreSQL/8.4/data/pg_log"
...
What's the Hi/Lo algorithm?
...keys (which are then held as a range in the server & used as needed):
select NEXT from KEY_ALLOC where SEQ=?;
update KEY_ALLOC set NEXT=(old value+200) where SEQ=? and NEXT=(old value);
Providing you can commit this transaction (use retries to handle contention), you have allocated 200 keys &...
Distinct by property of class with LINQ [duplicate]
...p:
List<Car> distinct =
cars
.GroupBy(car => car.CarCode)
.Select(g => g.First())
.ToList();
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Visual Studio 2013 and BitBucket
...oject!
In your "Solution Explorer", right click on your solution name, and select "Add Solution to Source Control ...".
Go to your "Team Explorer" and click on the "Manage Connections" icon on the top.
Double click on your Repository name under the "Local Git Repositories" section.
Now click on the ...
Git error: “Host Key Verification Failed” when connecting to remote repository
...the same mistake as me. You need to type yes. Simply hitting enter doesn't select yes by default
– JolonB
May 24 at 22:20
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