"Vista" <abc@gmai.com> wrote in message
news:f6ev6r$4b8$1@news.Stanford.EDU...
> Hi all,
>
> Please, allow me to ask this naive question...
>

It's not the language, it's the compiler.



> I am mainly a programmer in Matlab. Often times for the sake of speed, I
> convert my Matlab program into C/C++, often with the aid of numerical
> libraries such as GSL, IMSL, MKL, etc.
>
> Now I am facing a numerical computation task which need quadruple
> precison. Please see below for a detailed description.
>
> I guess Intel Visual Fortran or other Fortran has natural support for the
> quadruple precision.
>
> I probably will have to pick up my Fortran book and do some Fortran
> programming. (I've touched a little bit of it some years ago).
>
> Now, speed if critical for my application. If somebody tells me that
> Fortran's support of Quadruple precision is about 10% faster than any
> other quadruple solution in any other libraries in C/C++, then I am going
> to turn to Fortran.
>
> If the consensus is that Fortran for numerical calculations is only 5%
> faster than C/C++, then I won't bother turn to Fortran.
>
> Thanks!
>
> -------------------------------
> Seeking the fastest numerical library for quadruple precision in
> C/C++/Fortran
> Hi all,
>
> I have some computation and simulation which need quadruple precision. I
> mean, the double precision is not enough, while high precision such as
> 1000
> digits is not needed, and that's too slow. I guess quadruple precision
> exactly fits my problem and should be much faster than double precision.
>
> Could anybody tell me if MS Visual C++, or Intel C, Intel Fortran have
> already got quadruple precision in them and they are fully supported on
> Intel based cpus? I guess Intel Fortran has quadruple precision, but since
> I
> prefer C/C++ so my first choices are within C/C++ languages.
>
> Moreover, do GSL, Intel MKL, and IMSL etc. have got quadruple precision
> support? I only need +, -, *, /, exp, and log.
>
> I eventually have to do everything in C/C++ so I am primarily looking for
> numerical libraries, instead of Matlab or Maple or Mathematica's symbolic
> capability.
>
> But if you know how to "simulate" quadruple precision in Matlab or Maple,
> or
> Mathematica, in order to see if an algorithm will overslow when converting
> into C/C++/Fortran, please let me know. I want to do the algorithm design
> in
> Matlab, and test if it will overflow, before converting everything into
> C/C++/Fortran.
>
> If you know how to "simulate" quadruple precision in Matlab, Maple or
> Mathematica even with the symbolic toolbox, please let me know too... this
> is for algorithm design and testing...
>
> Moreover, are there popular quadruple precision packages? Please recommend
> the fastest one. I am really in huge need of speed.
>
> Thank you very much!
> ------------------------------------------------
>
>