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1d
comment Mathlink returning wrong output
Sounds like an issue with stray definitions. I can't see any other reason why some symbols should unexpectedly change into something completely different.
1d
comment Count the sequences in an array
It works, and it is faster. Its run time does not seem to be sensitive to whether the input is packed or not, and is 85% that of Michael's in the packed case, and 60% otherwise. (I upvoted before I checked this, because I had faith... but I was not expecting the performance to be insensitive to packing.)
1d
comment Graphs making on Mathematica by using HAM
Even a clairvoyant would have trouble with this question. I vote to close, because no detail is given about what the problem is or in what circumstances it occurs.
1d
revised Faster binary Hamming weight for big integers?
added 223 characters in body
1d
awarded  Nice Answer
2d
comment Faster binary Hamming weight for big integers?
@Mr.Wizard I do not understand that error at all. WolframLibraryVersion 2 is Mathematica 9. I can only assume that there is some problem in Mathematica 10 with backward-compatibility of LibraryLink libraries? Unfortunately, there is not much I can do about it for now. Are you free in the chat to talk about GCC?
2d
comment Faster binary Hamming weight for big integers?
I'm sorry about that. I hope this one will work better. Please let me know whether it does or not. I will need to delete this soon because it is not really legitimate to statically link GNU libgomp (which is GPLv3) into a DLL and then distribute it.
2d
comment Faster binary Hamming weight for big integers?
@Mr.Wizard I will be interested to hear if the DLL runs and what its comparative speed is like on your computer.
2d
comment Faster binary Hamming weight for big integers?
@Mr.Wizard well, shall I just send you the DLL? Here it is. (Virus checked with Virustotal, but exercise your own caution.) Compiled for a Core 2 processor, but should work on anything more recent. (I can help you with GCC another time, if you don't mind. It is quite a complex process.)
2d
comment Fastest way to measure Hamming distance of integers
If you are still interested in this, please see this question and my answer. I realised that you can deal with large integers simply by using IntegerDigits to partition them into machine-size chunks.
2d
answered Faster binary Hamming weight for big integers?
2d
comment Faster binary Hamming weight for big integers?
No; I take my comment back. It is the large number of times that BitAnd is called, not BitAnd itself, that leads to slowness. BitAnd by itself works as fast as BitShiftLeft. This will probably be a hazard for most of the bit-manipulation methods you reference.
Jul
2
revised Removing imaginary and negative results from Solve
deleted 6 characters in body
Jul
2
comment Exporting Dataset to WDX format fails
If HDF5 is the winner, would this mean that HDF5 support in general will be extended? It would be nice if so. HDF5 is very fast and the format seems to be very general, but at the moment its support in Mathematica is only really good enough for storing numerical arrays.
Jul
2
comment Exporting Dataset to WDX format fails
@LeonidShifrin by cross-platform, do you mean Windows/Mac/Linux all running on x86 processors? Or is it really cross-platform, portable to ARM as well? If the latter, I would certainly agree that WDX is functionally obsolete.
Jul
2
comment Character Encoding Method
Bear in mind that it is not possible to "detect" this except heuristically. So unless you want to write your own code to do this, or call Python, I expect that the answer is no.
Jul
2
comment NonlinearModelFit errors and precision
Your question is reopened. If you do not want to use the ComplexFit package but still do not want complex numbers, then you should add a constraint to prevent these appearing, or give better initial guesses.
Jul
2
comment R^2 values for piecewise regression
Is there a good reason why you want Mathematica to give you this result directly rather than calculating it for yourself from the data and the best-fit expression? If yes, please add that to the question. The main problem is, I am not absolutely sure that such a value can be calculated or interpreted unambiguously since the fit is global.
Jul
2
comment Limit of Nested Radical $\sqrt{1+\sqrt[2!]{2^2+\sqrt[3!]{3^3+…}}}$
The expression given in the question looks a bit funny to me. Why is it Sqrt[1 + ...] rather than 1 + (...)^(1/2!)? @ChipHurst's suggestion seems "nicer". Maybe you really want the square root of that result, but it could perhaps help to clarify this.
Jul
2
comment What function generates random numbers in a compiled function?
You may also like to note that many modern CPUs have a built-in physical random number generator. It may not be suitable (by itself) for cryptographic purposes because its implementation is not totally open and robust against hijacking, but since it is based on thermal noise, there are good physical reasons to suppose that it will produce good-quality random output.