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Why were pandas merges in python faster than data.table merges in R in 2012?
...els) is large: 10,000.
Does Rprof() reveal most of the time spent in the call sortedmatch(levels(i[[lc]]), levels(x[[rc]])? This isn't really the join itself (the algorithm), but a preliminary step.
Recent efforts have gone into allowing character columns in keys, which should resolve that issue ...
What is the difference between synchronous and asynchronous programming (in node.js)
...ile Node itself is single threaded, there are some task that can run in parallel. For example, File System operations occur in a different process.
That's why Node can do async operations: one thread is doing file system operations, while the main Node thread keeps executing your javascript code....
How to run Rake tasks from within Rake tasks?
...method?
task :build => [:some_other_tasks] do
build
end
task :build_all do
[:debug, :release].each { |t| build t }
end
def build(type = :debug)
# ...
end
If you'd rather stick to rake's idioms, here are your possibilities, compiled from past answers:
This always executes the task, bu...
SQL NVARCHAR and VARCHAR Limits
All, I have a large (unavoidable) dynamic SQL query. Due to the number of fields in the selection criteria the string containing the dynamic SQL is growing over 4000 chars. Now, I understand that there is a 4000 max set for NVARCHAR(MAX) , but looking at the executed SQL in Server Profiler for the ...
How to make a website secured with https
I have to build a small webapp for a company to maintain their business data... Only those within the company will be using it, but we are planning to host it in public domain, so that the employees can connect to app from various locations. (Till now I have built web apps that are hosted internall...
Javascript when to use prototypes
...ods, over and over.
Instead, those methods are defined on a prototype and all jQuery objects "inherit" that prototype so as to gain all those methods at very little runtime cost.
One vitally important part of how jQuery gets it right is that this is hidden from the programmer. It's treated purely ...
Redefining NULL
...ull pointer as a boolean must be false. This can be a bit awkward if you really do want a zero address, and NULL is not the zero address.
Nevertheless, with (heavy) modifications to the compiler and standard library, it's not impossible to have NULL be represented with an alternate bit pattern whil...
Everyauth vs Passport.js?
...auth makes extensive use of promises, instead of Node's approach of using callbacks and closures. Promises are an alternative approach to async programming. While useful in some high-level situations, I wasn't comfortable with an authentication library forcing this choice upon my application.
Fur...
How can I convert my device token (NSData) into an NSString?
...nvert the deviceToken to a String, you can do as follows:
func application(_ application: UIApplication, didRegisterForRemoteNotificationsWithDeviceToken deviceToken: Data) {
let token = deviceToken.map { String(format: "%02.2hhx", $0) }.joined()
print(token)
}
Old answer using NSData:
func...
What is the meaning of the planned “private protected” C# access modifier?
As part of the Roslyn documentation on GitHub, there's a page called Language feature implementation status , with planned language features for C# and VB.
...