Re: Calculators and calculating.

"Stan Brown" <the_stan_brown@xxxxxxxxxxx> wrote in message
news:MPG.1d7d4601c9725e0b989684@xxxxxxxxxxxxxxxxxxxxxx
> In article <43136680.2BF1A81D@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx>,
> jim.sprigs@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx favored us with...
>> Brian Reay wrote:
>> > The Sinclair Cambridge 100 is a later model and, as I recall, wasn't
>> > RPL.
>> > However, the (I believe) first Sinclair Scientific was RPL. To multiply
>> > 2 by
>> > 3 you would press:
>> > 2 + 3 x
>>
>> 2 x 3 in Polish is x 2 3 and in reverse Polish is 2 3 x. I.e. push 2 on
>> the stack, push 3 on the stack, pop the top two items off the stack and
>> push their product on the stack.
>
> The HP-35, introduced in 1973, described itself as operating by RPL.
> The multiplication would be done by 2 [ENTER] 3 [x], which is pretty
> much what Brian said.

Indeed. The use of the + (instead of the ENTER, which the Sinclair didn't
have) was the delimiter that said "I've entered my first number, push it on
the stack."

As you say, the HPs had an ENTER key (a long key as I recall). Sinclair
always saved every penny by clever tricks, like using the + key for the same
purpose.

Sinclair abandoned RPL soon after the first Scientific and followed the
trend toward normal algebraic entry- although it was sometime before that
trend allowed for BODMAS. I think it was Texas who first had true algebraic
entry. I had a TI58 which, I think, was one of the first with "AOS". That
must have been 1978 or so.

--
73
Brian, G8OSN
www.g8osn.org.uk


.

Relevant Pages

  • Re: Calculators and calculating.
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  • Re: Calculators and calculating.
    ... > Brian Reay wrote: ... > the stack, push 3 on the stack, pop the top two items off the stack and ... > push their product on the stack. ... The HP-35, introduced in 1973, described itself as operating by RPL. ...
    (uk.education.maths)
  • Re: forth and RPN/RPL
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