9 Jun
2017
9 Jun
'17
4:29 a.m.
On 2017-06-07 19:01, "Ron Natalie"<ron(a)ronnatalie.com> wrote:
The original FORTRAN and BASIC arrays started indexing
at one because everybody other than computer scientists start counting at 1.
FORTRAN, yes. BASIC (which dialect might we be talking about?) normally
actually start with 0. However, BASIC is weird, in that the DIM
statement is actually specifying the highest usable index, and not the
size of the array.
Thus:
DIM X(10)
means you get an array with 11 elements. So, people who wanted to use
array starting at 1 would still be happy, and if you wanted to start at
0, that also worked. You might unintentionally have a bit of wasted
memory, though.
These languages were for scientists and the beginner,
so you wanted to make things compatible with their normal concepts.
True.
PASCAL on the other hand required you to give the
minimum and maximum index for the array.
In a way, PASCAL makes the most sense. You still what range you want,
and you get that. Anything works, and it's up to you.
That said, PASCAL could get a bit ugly when passing arrays as arguments
to functions because of this.
Of course, C’s half-assaed implementation of arrays
kind of depends on zero-indexing to work.
:-)
Johnny
--
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|| on a psychedelic trip
email: bqt(a)softjar.se || Reading murder books
pdp is alive! || tryin' to stay hip" - B. Idol
9 Jun
9 Jun
5:16 a.m.
New subject: Array index history
FORTRAN, yes. BASIC (which dialect might we be talking
about?) normally
actually start with 0. However, BASIC is weird, in that the DIM
statement is
actually specifying the highest usable index, and not the size of the array.
Eh? Not in any BASIC I ever used. They all started at 1. Can't vouch
for the later Microsoft "visual" variants but the original 1970's era
BASIC
started with 1.
DIM X(10) gave you ten elements from 1...10
5:41 a.m.
New subject: Array index history
On Thu, 8 Jun 2017, Ron Natalie wrote:
All M$ dialects that I am aware of start at 0 by default. Later ones have
OPTION BASE to change this or let you do DIM X(5 TO 7) if you want.
-uso.
FORTRAN, yes. BASIC (which dialect might we be
talking about?) normally
actually start with 0. However, BASIC is weird, in that
the DIM statement is
actually specifying the highest usable index, and not the size of the array.
Eh? Not in any BASIC I ever used. They all started at 1. Can't vouch
for the later Microsoft "visual" variants but the original 1970's era
BASIC
started with 1.
DIM X(10) gave you ten elements from 1...10 
9:12 p.m.
New subject: Array index history
On Thu, Jun 8, 2017, at 19:41, Steve Nickolas wrote:
On Thu, 8 Jun 2017, Ron Natalie wrote:
In fact, they give you eleven elements from 0 to 10, which means that
code which *uses* 1..10 is compatible but wastes some space.
DIM X(10) gave you ten elements from 1...10
All M$ dialects that I am aware of start at 0 by default.
10:30 p.m.
New subject: Array index history
I stand corrected. I pulled up the original typewritten Dartmouth BASIC manual and
indeed the indices start at zero (though many coding examples don't write the zeroth
element). By default arrays were 11 elements long. You could change that with the DIM
statement. Yes, the value given to DIM is the highest index making a DIM A(20) defining
a 21 element array.
-----Original Message-----
From: TUHS [mailto:tuhs-bounces@minnie.tuhs.org] On Behalf Of Random832
Sent: Friday, June 9, 2017 11:12 AM
To: tuhs(a)minnie.tuhs.org
Subject: Re: [TUHS] Array index history
On Thu, Jun 8, 2017, at 19:41, Steve Nickolas wrote:
On Thu, 8 Jun 2017, Ron Natalie wrote:
In fact, they give you eleven elements from 0 to 10, which means that code which *uses*
1..10 is compatible but wastes some space.
DIM X(10) gave you ten elements from 1...10
All M$ dialects that I am aware of start at 0 by default. 
6:21 a.m.
New subject: Array index history
All variants of BASIC by DEC does this. A few others I've tried also do. But since
BASIC was not standardized for the longest time, it's hard to claim that BASIC really
was one way or another. I have definitely not tried every dialect that has existed.
Johnny
Ron Natalie <ron(a)ronnatalie.com> skrev: (9 juni 2017 01:16:48 CEST)
--
Skickat från min Android-enhet med K-9 Mail. Ursäkta min fåordighet.
FORTRAN, yes. BASIC (which dialect might we be
talking about?)
normally
actually start with 0. However, BASIC is weird, in that the DIM
statement is
actually specifying the highest usable index, and not the size of the
array.
Eh? Not in any BASIC I ever used. They all started at 1. Can't
vouch
for the later Microsoft "visual" variants but the original 1970's era
BASIC
started with 1.
DIM X(10) gave you ten elements from 1...10 
6:25 a.m.
New subject: Array index history
On 09/06/2017 00:16, Ron Natalie wrote:
Well, my experience matches Johnny's. I used many derivatives of
MicroSoft BASIC - PET, Apple INTBASIC, Applesoft, Exidy Sorcerer, and
others - and they all start at 0. AFAIR HP BASIC did so as well. The
original 1960s Dartmouth BASIC (for which I have a copy of the manual)
also started at 0 (cf. page 38); indeed if you didn't explicitly DIM an
array, you got eleven elements indexed 0...10.
--
Pete
Pete Turnbull
FORTRAN, yes. BASIC (which dialect might we be
talking about?) normally
actually start with 0. However, BASIC is weird, in that
the DIM statement is
actually specifying the highest usable index, and not the size of the array.
Eh? Not in any BASIC I ever used. They all started at 1. Can't vouch
for the later Microsoft "visual" variants but the original 1970's era
BASIC
started with 1.
DIM X(10) gave you ten elements from 1...10 
7:19 a.m.
New subject: Array index history
On 2017-06-08 8:25 PM, Pete Turnbull wrote:
On 09/06/2017 00:16, Ron Natalie wrote:
Well, my experience matches Johnny's. I used many derivatives of
MicroSoft BASIC - PET, Apple INTBASIC, Applesoft, Exidy Sorcerer, and
others - and they all start at 0. AFAIR HP BASIC did so as well. The
original 1960s Dartmouth BASIC (for which I have a copy of the manual)
also started at 0 (cf. page 38); indeed if you didn't explicitly DIM an
array, you got eleven elements indexed 0...10.
I wrote a lot of BBC BASIC. DIM(9) allocates ten elements, 0..9,
according to this:
http://www.riscos.com/support/developers/bbcbasic/part2/arrays.html
--Toby
FORTRAN, yes. BASIC (which dialect might we be
talking about?) normally
actually start with 0. However, BASIC is weird, in that
the DIM
statement is
actually specifying the highest usable index, and not the size of the
array.
Eh? Not in any BASIC I ever used. They all started at 1. Can't vouch
for the later Microsoft "visual" variants but the original 1970's era
BASIC
started with 1.
DIM X(10) gave you ten elements from 1...10
8:14 a.m.
New subject: Array index history
On 09/06/2017 02:19, Toby Thain wrote:
I wrote a lot of BBC BASIC. DIM(9) allocates ten
elements, 0..9,
Yes, all versions (of which there are at least nine, going back to
1981), and so too does its predecessor, Atom BASIC. Indexing from zero
was the norm in 1970s/1980s BASICs.
--
Pete
Pete Turnbull
2753
days inactive
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days old
8 comments
7 participants
participants (7)
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Johnny Billquist -
Johnny Billquist -
Pete Turnbull -
Random832 -
Ron Natalie -
Steve Nickolas -
Toby Thain