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From: rap@csadfa.cs.adfa.oz.au (Robert Pearson)
Newsgroups: comp.lang.fortran
Subject: Re: What is the FORTRAN for ?
Message-ID: <1784@ccadfa.adfa.oz.au>
Date: 1 Aug 90 03:23:16 GMT
References: <65460@lll-winken.LLNL.GOV>
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From article <65460@lll-winken.LLNL.GOV>, by jac@gandalf..llnl.gov (James Crotinger):
>   As many people have pointed out, FORTRAN is well suited for writing
> numerical codes. C isn't necessarily as well suited for this.
> 
>>As many people have expressed, Fortran usually produces the fastest
>>code on many high end systems.  It is also typically far better
>>supported than any other language, which is a bit unfortunate.  
> 
>   I'm not sure what Maurice means by "supported" here. My experience
> has been that software development tools for C are for more developed
> on most systems (CRAYs excluded) than those for Fortran. I'd give
> my eye teeth for a Saber C type environment that would work with 
> Fortran as well as C and C++. 
    just to add my opinions I have had many years programming fortran
from the very early CDC through to current supers.
   At the moment I have about 12,000 lines of code (most C ) for a 
computationally intensive task which can be written to be suitable for a vector
processor.
  BUT  the main structure is a tree.
    ideal for pointers to complex structures.
 HOWEVER
   multidimensional arrays in C are a PAIN
   espescially if one wants to pass part of the array
     FORTRAN A(30,30,50)
     call b (a(1,1,nold)
       where in b is
        a(30,30)
  C does work
      b(&a[nold][0][0]);
  and can actually let the fortran treat  'a'as a variable dimension array
 BUT tfortran automatically converts most of my code to vectors
   C requires all sorts of nasty tricks 
   I have had to experiment to find code that will give a vector
  and worse in one part of the code  will give vector;
   splitting up not necessarily
  works as vector.
   chnging from defined to global or local may also change the
vector ???? : wish I understood it all    !!!!
  the problem is not the compilers so much as the specification
that ARRAYS and POiNTERS are EQIVALENT
   how the people who write any compilers for vector processors that
can handle this problem is past me, and I am actually amazed that they have 
done relatively well
   for those interested the code has been published in
 IJHSC  Vol 2 85-100
  My solution would be to write C for the pointers and convert to fortran
for the rest. Also a PAIN

Robert  Pearson			 ISD:	+61 62 68 8171  STD: (062) 68 8171
Dept. Computer Science		 Telex:	ADFADM AA62030
University College	      ACSNET:	rap@csadfa.oz
Aust. Defence Force Academy	UUCP:	...!uunet!munnari!csadfa.oz!rap
Canberra. ACT. 2600.		ARPA:	rap%csadfa.oz@uunet.uu.net
AUSTRALIA		       CSNET:	rap@csadfa.oz
Robert  Pearson			 ISD:	+61 62 68 8171  STD: (062) 68 8171
Dept. Computer Science		 Telex:	ADFADM AA62030
University College	      ACSNET:	rap@csadfa.oz
Aust. Defence Force Academy	UUCP:	...!uunet!munnari!csadfa.oz!rap