Re: The answer to "Can Ada replace FORTRAN for numerical computation?

[Niklas Holsti <niklas.holsti@tidorum.invalid>]

On 19-08-05 20:15 , Optikos wrote:
> On Monday, August 5, 2019 at 9:35:10 AM UTC-5, Shark8 wrote:
>> On Saturday, August 3, 2019 at 6:30:36 AM UTC-6, Nasser M. Abbasi
>> wrote:
>>> There are also significant limitation to Ada as a language for
>>> scientific computation, in particular with regard to dynamic
>>> typing and storage allocation.
>>
>> I think this is referring to things like dynamically-sized arrays,
>> rather than "X is an integer there, now it's a String!" when
>> talking about dynamic-typing, as it's obvious that the latter would
>> obliviate the aforementioned properties of finding conceptual
>> errors.
>
> But there are 2 usages of considering something an integer for the
> moment in a few lines of code.  One is to floor-truncate a floating-
> or fixed-point number to an integer; Ada supports syntax for this
> semantic meaning.

Yes of course.

> But another is to consider a floating-point
> representation as a machine-word to perform integer-based bit
> twiddling to conform the representation of the floating-point number
> to some machine requirements or machine representation that Ada's
> syntax and semantics lacks; pre-1995 Ada (the subject matter of the
> paper referenced) was abysmal at this commonplace use case in
> Fortran, PL/I, and C.

No, record types with representation clauses plus Unchecked_Conversion 
were fully able to handle this case, already in Ada 83.

>> As to the storage-allocation, I suspect it is also referring to Ada
>> arrays needing definite bounds in certain cases -- the ability to
>> return properly-sized arrays from a function *should* be enough to
>> ease this complaint *EXCEPT*, perhaps, when dealing with Very Large
>> Arrays.

They may also have been scared by the "Unchecked" in 
Unchecked_Deallocation. The identifier "free" is so much more friendly 
and safe-sounding...

> Again, Ada has had a storage-pool wisdom at the heart of its storage
> allocation strategies, but pre-1995 Ada staunchly lacked PL/I's and
> Fortran's and C's ability to ecumenically reach out and
> read/write/manipulate some other language's in-memory storage format,
> as a I-got-you-covered system-programming duty.

I doubt your statement. There is nothing in Fortran or C that supports 
"other languages' formats", and you can do any format manipulations you 
want with Ada 83 as well as with Fortran or C. Please show a 
counter-example if you insist on this point.

-- 
Niklas Holsti
Tidorum Ltd
niklas holsti tidorum fi
       .      @       .