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When to use enumerateObjectsUsingBlock vs. for
...
Ultimately, use whichever pattern you want to use and comes more naturally in the context.
While for(... in ...) is quite convenient and syntactically brief, enumerateObjectsUsingBlock: has a number of features that may or may not prove interesting:
enumerateObjectsUsingBlock: will...
Why is SCTP not much used/known
...r is connected too (MSC).
The telecom area is moving to higher speeds and more reachable environment. One of these changes is to replace SS7 protocol by some more elegant, fast and flexible IP-based protocol.
The telecom area is very conservative. The SS7 network has been used here for decades. It...
Is there a performance difference between CTE , Sub-Query, Temporary Table or Table Variable?
...ame information to the query optimizer. One difference is that a CTE used more than once could be easily identified and calculated once. The results could then be stored and read multiple times. Unfortunately, SQL Server does not seem to take advantage of this basic optimization method (you might...
Java: when to use static methods
... involves two Car objects, and still want it to be static. E.g.:
Car theMoreEfficientOf( Car c1, Car c2 )
Although this could be converted to a non-static version, some would argue that since there isn't a "privileged" choice of which Car is more important, you shouldn't force a caller to choos...
How efficient is locking an unlocked mutex? What is the cost of a mutex?
...le locks would increase parallelism. At the cost of maintainability, since more locking means more debugging of the locking.
How efficient is it to lock a mutex? I.e. how much assembler instructions are there likely and how much time do they take (in the case that the mutex is unlocked)?
The p...
Angular HttpPromise: difference between `success`/`error` methods and `then`'s arguments
...omise (resolved with a value returned from a callback) while .success() is more traditional way of registering callbacks and doesn't return a promise.
Promise-based callbacks (.then()) make it easy to chain promises (do a call, interpret results and then do another call, interpret results, do yet a...
Performance optimization strategies of last resort [closed]
... code, bringing the time down to 20 seconds.
Now the largest time-taker is more list-building. As a percentage, it was not so big before, but now it is because the bigger problem was removed. I find a way to speed it up, and the time drops to 17 seconds.
Now it is harder to find obvious culprits, bu...
Where can I learn how to write C code to speed up slow R functions? [closed]
...s real, tested examples to study and adapt.
But as Josh suspected, I lean more towards C++ and hence Rcpp. It also has plenty of examples.
Edit: There were two books I found helpful:
The first one is Venables and Ripley's "S Programming" even though it is getting long in the tooth (and there hav...
How do I get currency exchange rates via an API such as Google Finance? [closed]
... use fixer.io instead due to stability issues.
Might be useful if you need more than just a CSV.
(thanks to Keyo) Yahoo Query Language lets you get a whole bunch of currencies at once in XML or JSON. The data updates by the second (whereas the European Central Bank has day old data), and stops in t...
What are the differences between Autotools, Cmake and Scons?
...no problems with the other options discussed in the thread here.
SCons is more of a replacement for Make/GMake/etc. and looks pretty nice, all things considered However...
It is still really more of a POSIX only tool. You could probably more easily get MinGW to build Windows stuff with this tha...