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What's the fastest way to merge/join data.frames in R?
..., in fact, they are placed on tables which were overwritten before the sql select ever runs and that, in part, accounts for why its so slow. The idea of sqldf is that the data frames in your R session constitute the data base, not the tables in sqlite. Thus each time the code refers to an unqualif...
Cannot convert lambda expression to type 'string' because it is not a delegate type [duplicate]
...ID == Value
orderby q.RowID descending
select q).FirstOrDefault();
Errors:
Error 241 Cannot convert lambda expression to type 'string' because it is not a delegate type
Error 242 Delegate 'System.Func<..>' does not take 1 arguments
Error 243 The name 'Valu...
FTP/SFTP access to an Amazon S3 Bucket [closed]
...also modifying the objects in the bucket. The value "30" in my system was selected somewhat arbitrarily.
-o enable_noobj_cache (default is disable)
enable cache entries for the object which does not exist. s3fs always has to check whether file(or sub directory) exists under object(path) when s3fs...
What are the various “Build action” settings in Visual Studio project properties and what do they do
... as a default... I'm referring to the BuildAction property for each file selected in Solution Explorer. There are a number of options and it's difficult to know what each one of them will do.
...
Android Studio: how to remove/update the “Created by” comment added to all new classes?
...lates in the left hand pane.
You have two ways you can change this...
1) Select the Includes tab and edit the Created by... text directly.
2) Select the Templates tab and edit the #parse("File Header.java") line for any template that you desire.
Personally I followed option 1) and made the d...
Xcode can only refactor C and Objective-C code. How to rename swift class name in Xcode 6?
...ame swift class from ViewController.swift to some other name. But when I select Refactor -> Rename, it gives error Xcode can only refactor C and Objective-C code .
...
Wrapping chained method calls on a separate line in Eclipse for Java
...ormatter → Edit → Line wrapping (tab)
Then, in the list at the left, select:
Function Calls → Qualified invocations
Now below this list, set Line wrapping policy to:
Wrap all elements, except first element if not necessary
Check:
Force split, even if line shorter than maximu...
Keyboard shortcuts are not active in Visual Studio with Resharper installed
...ou can look at the Visual Studio Integration options for ReSharper by...
Select ReSharper > Options... from the Visual Studio menu
Select the Visual Studio Integration item on the Options window
The bottom of the page gives instructions on how to reset the keyboard scheme.
If that doesn't w...
What is the difference between Left, Right, Outer and Inner Joins?
...ow you begin your query impacts the outcome of the join type. For example, SELECT * FROM students RIGHT OUTER JOIN lockers... would result in a different outcome than SELECT * FROM lockers RIGHT OUTER JOIN students.... Great answer, but would love to see it updated with complete SQL queries
...
Will #if RELEASE work like #if DEBUG does in C#?
...nstant defined for release mode. Check your project settings under build.
Selecting [Define DEBUG constant] under Project -> Build is like including #define DEBUG at the beginning of every file.
If you want to define a RELEASE constant for the release configuration go to:
Project Properties ...