“Why do arrays start at 0?"
https://buttondown.email/hillelwayne/archive/why-do-arrays-start-at-0/

"It's not the reason you think. No, it's not that reason either.”

My Fortran starts at one. My C++ starts at zero. This has made my life
hell.

Lynn

On 8/26/2022 3:49 PM, Lynn McGuire wrote:
> “Why do arrays start at 0?"
>    https://buttondown.email/hillelwayne/archive/why-do-arrays-start-at-0/
>
> "It's not the reason you think. No, it's not that reason either.”
>
> My Fortran starts at one.  My C++ starts at zero.  This has made my life
> hell.
>
> Lynn
>
Fortran was there first...and got it right...you can change Fortran to
start at other index values for many cases.

On 8/26/2022 2:49 PM, Lynn McGuire wrote:
> “Why do arrays start at 0?"
> https://buttondown.email/hillelwayne/archive/why-do-arrays-start-at-0/
>
> "It's not the reason you think. No, it's not that reason either.”
>
> My Fortran starts at one.  My C++ starts at zero.  This has made my
> life hell.
>

Here's a crude outline of a solution:

If you want a C++ array index to start at 1, make the array one element
bigger than necessary, and start indexing at 1, just like in Fortran.
Element 0 will be unused.

If you want a C++ array to map exactly to a Fortran array, but with an
index starting at 1, wrap the C++ array in a class and overload the
subscripting operator(s) to subtract 1 from the index.

Neither of these approaches seems elegant, but one of them should be
less hellish than the other.

Louis

On Fri, 26 Aug 2022 15:49:51 -0500
Lynn McGuire <lynnmcguire5@gmail.com> wrote:

> “Why do arrays start at 0?"
> https://buttondown.email/hillelwayne/archive/why-do-arrays-start-at-0/
>
> "It's not the reason you think. No, it's not that reason either.”
>
> My Fortran starts at one. My C++ starts at zero. This has made my
> life hell.

Fortran is retarded.

/Flibble

On Fri, 26 Aug 2022 16:56:47 -0500
Gary Scott <garylscott@sbcglobal.net> wrote:

> On 8/26/2022 3:49 PM, Lynn McGuire wrote:
> > “Why do arrays start at 0?"
> >    https://buttondown.email/hillelwayne/archive/why-do-arrays-start-at-0/
> >
> > "It's not the reason you think. No, it's not that reason either.”
> >
> > My Fortran starts at one.  My C++ starts at zero.  This has made my
> > life hell.
> >
> > Lynn
> >
> Fortran was there first...and got it right...you can change Fortran
> to start at other index values for many cases.

Being first doesn't make you correct. Fortran is retarded.

/Flibble

On Friday, August 26, 2022 at 2:56:51 PM UTC-7, Gary Scott wrote:

(snip)
> Fortran was there first...and got it right...you can change Fortran to
> start at other index values for many cases.

ALGOL 60 has the [lower:upper] form, presumably back to 1960.

I have, at least a few times, converted programs from one to the other,
and yes it is amazingly easy to get wrong.

On 8/26/22 19:46, Mr Flibble wrote:
> On Fri, 26 Aug 2022 16:56:47 -0500
> Gary Scott <garylscott@sbcglobal.net> wrote:
>
>> On 8/26/2022 3:49 PM, Lynn McGuire wrote:
>>> “Why do arrays start at 0?"
>>>    https://buttondown.email/hillelwayne/archive/why-do-arrays-start-at-0/
>>>
>>> "It's not the reason you think. No, it's not that reason either.”
>>>
>>> My Fortran starts at one.  My C++ starts at zero.  This has made my
>>> life hell.
>>>
>>> Lynn
>>>
>> Fortran was there first...and got it right...you can change Fortran
>> to start at other index values for many cases.
>
> Being first doesn't make you correct. Fortran is retarded.
>
> /Flibble
>
A reasonable language would let you specify the lower index. Fortran
and C are both retarded.

On Friday, August 26, 2022 at 7:30:05 PM UTC-7, d thiebaud wrote:

(snip)

> A reasonable language would let you specify the lower index. Fortran
> and C are both retarded.

Since it hasn't been mentioned yet, note the complication with
Fortran of subroutine arguments. Sometimes the dummy array
has origin 1, even when the actual argument doesn't. Sometimes.

Not that there is an easy answer, but it is a very confusing part
of Fortran arrays.

On Saturday, August 27, 2022 at 6:49:55 AM UTC+10, Lynn McGuire wrote:
> “Why do arrays start at 0?"
> https://buttondown.email/hillelwayne/archive/why-do-arrays-start-at-0/
>
> "It's not the reason you think. No, it's not that reason either.”
>
> My Fortran starts at one. My C++ starts at zero. This has made my life
> hell.
..
FORTRAN followed centuries-old mathematical convention.
FORTRAN started at 1 for subscripts.
It's now been the default, since lower bounds were introduced.

PL/I has always allowed lower bounds other than 1,
the default being 1.

On Saturday, August 27, 2022 at 12:30:05 PM UTC+10, d thiebaud wrote:

> A reasonable language would let you specify the lower index. Fortran
> and C are both retarded.
..
Fortran allowes the lower bound to be specified.

d thiebaud <thiebauddick2@aol.com> writes:
> On 8/26/22 19:46, Mr Flibble wrote:
>> On Fri, 26 Aug 2022 16:56:47 -0500
>> Gary Scott <garylscott@sbcglobal.net> wrote:
>>
>>> On 8/26/2022 3:49 PM, Lynn McGuire wrote:
>>>> “Why do arrays start at 0?"
>>>>    https://buttondown.email/hillelwayne/archive/why-do-arrays-start-at-0/
>>>>
>>>> "It's not the reason you think. No, it's not that reason either.”
>>>>
>>>> My Fortran starts at one.  My C++ starts at zero.  This has made my
>>>> life hell.
>>>>
>>>> Lynn
>>>>
>>> Fortran was there first...and got it right...you can change Fortran
>>> to start at other index values for many cases.
>> Being first doesn't make you correct. Fortran is retarded.
>> /Flibble
>>
> A reasonable language would let you specify the lower index. Fortran
> and C are both retarded.

"Mr Flibble" is a troll, and I'm sure he's aware that "retarded" is an
offensive word. Are you?

--
Keith Thompson (The_Other_Keith) Keith.S.Thompson+u@gmail.com
Working, but not speaking, for Philips
void Void(void) { Void(); } /* The recursive call of the void */

Lynn McGuire <lynnmcguire5@gmail.com> schrieb:
> “Why do arrays start at 0?"
> https://buttondown.email/hillelwayne/archive/why-do-arrays-start-at-0/
>
> "It's not the reason you think. No, it's not that reason either.”
>
> My Fortran starts at one. My C++ starts at zero. This has made my life
> hell.

If you want to declare your Fortran arrays to start at zero, just
declare them with a lower bound of zero, like

real, dimension(0:n-1) :: a

On Saturday, August 27, 2022 at 5:31:37 AM UTC+2, Robin Vowels wrote:
> On Saturday, August 27, 2022 at 6:49:55 AM UTC+10, Lynn McGuire wrote:
> FORTRAN followed centuries-old mathematical convention.
Nope. Just as the linked article mentions, in Mathematics, starting an index from 0 or 1 are both often used, e.g., for elements of sequences and series, 0 seems to be most often used, for vector and matrix indices, 1. If a convergence of a sequence is considered, you often don't care about "early" elements, so, if that yields a simple formula, you start from any number convenient. In Physics, you often start vector and matrix indices with 0 if the zeroth component is in some sense distinguished (e.g., in relativistic theories, distinguishing the time-like coordinate from the 3 space-like ones).
> FORTRAN started at 1 for subscripts.

On Saturday, August 27, 2022 at 1:48:15 AM UTC-7, fiz...@gmail.com wrote:
> On Saturday, August 27, 2022 at 5:31:37 AM UTC+2, Robin Vowels wrote:
> > On Saturday, August 27, 2022 at 6:49:55 AM UTC+10, Lynn McGuire wrote:
> > FORTRAN followed centuries-old mathematical convention.
> Nope. Just as the linked article mentions, in Mathematics, starting an index
> from 0 or 1 are both often used, e.g., for elements of sequences and series,
> 0 seems to be most often used, for vector and matrix indices, 1.

Yes, so array indexing is 1. Series sums start at zero, but are not indexed.

> If a convergence of a sequence is considered, you often don't care about
>"early" elements, so, if that yields a simple formula, you start from any
> number convenient.

Now for this case, you want a DO loop to start at zero, which Fortran 66
didn't allow. But you normally sum inside the loop, not store element
in an array.

> In Physics, you often start vector and matrix indices with 0 if the zeroth
> component is in some sense distinguished (e.g., in relativistic theories,
> distinguishing the time-like coordinate from the 3 space-like ones).
Yes, four-vectors.

gah4 <gah4@u.washington.edu> schrieb:
> On Saturday, August 27, 2022 at 1:48:15 AM UTC-7, fiz...@gmail.com wrote:
>> On Saturday, August 27, 2022 at 5:31:37 AM UTC+2, Robin Vowels wrote:
>> > On Saturday, August 27, 2022 at 6:49:55 AM UTC+10, Lynn McGuire wrote:
>> > FORTRAN followed centuries-old mathematical convention.
>> Nope. Just as the linked article mentions, in Mathematics, starting an index
>> from 0 or 1 are both often used, e.g., for elements of sequences and series,
>> 0 seems to be most often used, for vector and matrix indices, 1.
>
> Yes, so array indexing is 1. Series sums start at zero, but are not indexed.
>
>> If a convergence of a sequence is considered, you often don't care about
>>"early" elements, so, if that yields a simple formula, you start from any
>> number convenient.
>
> Now for this case, you want a DO loop to start at zero, which Fortran 66
> didn't allow.

Really? You mean that

DO 10 I=0,1

would not be allowed?

You probably meant zero-trip loops which were undefined.

On Fri, 26 Aug 2022 22:05:17 -0700
Keith Thompson <Keith.S.Thompson+u@gmail.com> wrote:

> d thiebaud <thiebauddick2@aol.com> writes:
> > On 8/26/22 19:46, Mr Flibble wrote:
> >> On Fri, 26 Aug 2022 16:56:47 -0500
> >> Gary Scott <garylscott@sbcglobal.net> wrote:
> >>
> >>> On 8/26/2022 3:49 PM, Lynn McGuire wrote:
> >>>> “Why do arrays start at 0?"
> >>>>    https://buttondown.email/hillelwayne/archive/why-do-arrays-start-at-0/
> >>>>
> >>>> "It's not the reason you think. No, it's not that reason either.”
> >>>>
> >>>> My Fortran starts at one.  My C++ starts at zero.  This has made
> >>>> my life hell.
> >>>>
> >>>> Lynn
> >>>>
> >>> Fortran was there first...and got it right...you can change
> >>> Fortran to start at other index values for many cases.
> >> Being first doesn't make you correct. Fortran is retarded.
> >> /Flibble
> >>
> > A reasonable language would let you specify the lower index. Fortran
> > and C are both retarded.
>
> "Mr Flibble" is a troll, and I'm sure he's aware that "retarded" is an
> offensive word. Are you?
Retarded isn't an offensive word but I could replace it with fucktarded
if that helps?

/Flibble

On Saturday, August 27, 2022 at 6:48:15 PM UTC+10, fiz...@gmail.com wrote:
> On Saturday, August 27, 2022 at 5:31:37 AM UTC+2, Robin Vowels wrote:
> > On Saturday, August 27, 2022 at 6:49:55 AM UTC+10, Lynn McGuire wrote:
> > FORTRAN followed centuries-old mathematical convention.
> Nope. Just as the linked article mentions, in Mathematics, starting an index from 0 or 1 are both often used, e.g., for elements of sequences and series, 0 seems to be most often used,
..
That's irrrelevnt to the OP's question.
..
for vector and matrix indices, 1.

That's what I said.
It's an old tradition.

> If a convergence of a sequence is considered, you often don't care about "early" elements, so, if that yields a simple formula, you start from any number convenient. In Physics, you often start vector and matrix indices with 0
..
Really? See above.
..
> if the zeroth component is in some sense distinguished (e.g., in relativistic theories, distinguishing the time-like coordinate from the 3 space-like ones).
..
> > FORTRAN started at 1 for subscripts.

Gary Scott <garylscott@sbcglobal.net> writes:
>On 8/26/2022 3:49 PM, Lynn McGuire wrote:
>> “Why do arrays start at 0?"
>>    https://buttondown.email/hillelwayne/archive/why-do-arrays-start-at-0/
>>
>> "It's not the reason you think. No, it's not that reason either.”
>>
>> My Fortran starts at one.  My C++ starts at zero.  This has made my life
>> hell.
>>
>> Lynn
>>
>Fortran was there first...and got it right...you can change Fortran to
>start at other index values for many cases.

There are around twenty languages that start array indicies with one. None of
them are low-level hardware-oriented languages (Burroughs algol excepted) like C. In the
hardware indicies start at zero by definition.

On Saturday, August 27, 2022 at 2:30:15 AM UTC-7, Thomas Koenig wrote:

(snip)

> > Now for this case, you want a DO loop to start at zero, which Fortran 66
> > didn't allow.

> Really? You mean that
> DO 10 I=0,1
> would not be allowed?
Yes, not allowed. And the IBM compilers wouldn't compile them
with a constant. BXLE works fine with variables, though.
That was another change in Fortran 77.

> You probably meant zero-trip loops which were undefined.

And yes, even though the standard said undefined, many compilers
implemented the one-trip minimum, with the test at the end.
And so many believed that was required.

On 8/27/22 01:47, Thomas Koenig wrote:
> Lynn McGuire <lynnmcguire5@gmail.com> schrieb:
>> “Why do arrays start at 0?"
>> https://buttondown.email/hillelwayne/archive/why-do-arrays-start-at-0/
>>
>> "It's not the reason you think. No, it's not that reason either.”
>>
>> My Fortran starts at one. My C++ starts at zero. This has made my life
>> hell.
>
> If you want to declare your Fortran arrays to start at zero, just
> declare them with a lower bound of zero, like
>
> real, dimension(0:n-1) :: a

Can you declare other lower bounds the same way?

Op 26.aug..2022 om 22:49 schreef Lynn McGuire:
> “Why do arrays start at 0?"
>    https://buttondown.email/hillelwayne/archive/why-do-arrays-start-at-0/
>
> "It's not the reason you think. No, it's not that reason either.”
>
> My Fortran starts at one.  My C++ starts at zero.  This has made my life
> hell.
>
> Lynn
>

I assumed that it was done because in C x[i] is equivalent to *(x+i).

On Saturday, August 27, 2022 at 3:19:26 PM UTC-4, d thiebaud wrote:
> On 8/27/22 01:47, Thomas Koenig wrote:
> > Lynn McGuire schrieb:
> >> “Why do arrays start at 0?"
> >> https://buttondown.email/hillelwayne/archive/why-do-arrays-start-at-0/
> >>
> >> "It's not the reason you think. No, it's not that reason either.”
> >>
> >> My Fortran starts at one. My C++ starts at zero. This has made my life
> >> hell.
> >
> > If you want to declare your Fortran arrays to start at zero, just
> > declare them with a lower bound of zero, like
> >
> > real, dimension(0:n-1) :: a
> Can you declare other lower bounds the same way?

Re: "Can you declare other lower bounds the same way?", yes.

Below is a simple example with the so-called assume-shape array parameters where array descriptors come into play during procedure invocation:

real :: x(2,3,4)
x = reshape( [( i, integer :: i = 1, size(x) )], shape=shape(x) )
call sub( x )
contains
subroutine sub( a )
real, intent(in) :: a( -1:, -2:, -3: )
print *, "lbound(a, dim=1) = ", lbound(a, dim=1)
print *, "lbound(a, dim=2) = ", lbound(a, dim=2)
print *, "lbound(a, dim=3) = ", lbound(a, dim=3)
print *, a
end subroutine
end

The program based on above source can produce the following output:
lbound(a, dim=1) = -1
lbound(a, dim=2) = -2
lbound(a, dim=3) = -3
1.000000 2.000000 3.000000 4.000000 5.000000
6.000000 7.000000 8.000000 9.000000 10.00000
11.00000 12.00000 13.00000 14.00000 15.00000
16.00000 17.00000 18.00000 19.00000 20.00000
21.00000 22.00000 23.00000 24.00000

On 8/27/2022 2:26 PM, Fred. Zwarts wrote:
> Op 26.aug..2022 om 22:49 schreef Lynn McGuire:
>> “Why do arrays start at 0?"
>>
>> https://buttondown.email/hillelwayne/archive/why-do-arrays-start-at-0/
>>
>> "It's not the reason you think. No, it's not that reason either.”
>>
>> My Fortran starts at one.  My C++ starts at zero.  This has made my
>> life hell.
>>
>> Lynn
>>
>
> I assumed that it was done because in C x[i] is equivalent to *(x+i).

Yup. So Fortran x(i) is equivalent to *(x+i-1). Or, the x is
subtracted from first: x--; *(x+i);.

Lynn

gah4 <gah4@u.washington.edu> schrieb:
> On Saturday, August 27, 2022 at 2:30:15 AM UTC-7, Thomas Koenig wrote:
>
> (snip)
>
>> > Now for this case, you want a DO loop to start at zero, which Fortran 66
>> > didn't allow.
>
>> Really? You mean that
>
>> DO 10 I=0,1
>
>> would not be allowed?
>
> Yes, not allowed.

I have the Fortran 66 standard before me, and I find no such
restriction in 7.1.2.8 (nor would it make sense at all).

Which part of the standard are you referring to?

d thiebaud <thiebauddick2@aol.com> schrieb:
> On 8/27/22 01:47, Thomas Koenig wrote:
>> Lynn McGuire <lynnmcguire5@gmail.com> schrieb:
>>> “Why do arrays start at 0?"
>>> https://buttondown.email/hillelwayne/archive/why-do-arrays-start-at-0/
>>>
>>> "It's not the reason you think. No, it's not that reason either.”
>>>
>>> My Fortran starts at one. My C++ starts at zero. This has made my life
>>> hell.
>>
>> If you want to declare your Fortran arrays to start at zero, just
>> declare them with a lower bound of zero, like
>>
>> real, dimension(0:n-1) :: a
>
> Can you declare other lower bounds the same way?

Yes.

You can, since 1991, when Fortran 90 was released, do

real, dimension(from:to) :: a

where from and to are arbitrary integer expressions. (If to <
from, then you get a zero-sized array, which is perfectly valid
and which just happens to have size zero and no element).

(In Fortran, you cannot declare variables in the middle of
code. If you want to do that, Fortran 2008 introduced the
BLOCK construct for declaring variables, much like
C's or C++'s { and }, so you can do

read (*,*) from, to
block
real, dimension(from:to) :: a
! Use a here
end block