[RsR] estimators based on random samples... - should be random

[Martin Maechler]

>>>>> "ValenT" == Valentin Todorov <valentin.todorov using chello.at>
>>>>>     on Wed, 10 May 2006 00:52:01 +0200 writes:

    >> By the way, Valentin,
    >> do you feel it is important to remain with Fortran there?
    >> In general, I end up 'f2c'ing (Fortran to C translating) Fortran
    >> source and work with C; not the least because I get better
    >> compiler warnings and easier debugging tools.

    ValenT> I am not happy with the Fortran in covMcd and ltsReg, but:
    ValenT> 1. I still do not believe in the automatic coversion (yes, you are right, I 
    ValenT> had first at least to try it)

    ValenT> 2. I would like to redesign the programs

    ValenT> 3. I would prefer C++ rather than C.

C++ complicates things slightly and typically is a tad (10% ?) slower than C.
R's C API is a C and not C++ API anyway.
I think it's only worth using C++ for some kind of problems
(e.g. when a class structure can make the program much more readable),
and I doubt that the covMcd() or ltsReg() algorithms belong to
this class.

    ValenT> For all these I still have not found enough time.

    ValenT> By the way my trials to download an f2c converter ended with the download of 
    ValenT> a "Free download Manager"! and nothing more. I'll appreciate some info.

f2c  is from the Bell Labs -- AFAIK by some of the same people
who invented C.  Good Linux distributions provide a package for
it. Googling 'f2c' gives a good site (http://www.netlib/org/f2c)
as first hit for me. 
I've used it -- plus an extra perl script I wrote myself --
many times in the past ten years; even parts of R itself were
done using it.

BTW, I thought of doing the conversion (for fast MCD & LTS)
     myself, rather than you having to do it.

Martin