HP-25 purpose

[Valentin Albillo]

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Hi,

(11-03-2020 01:04 AM)Matt Agajanian Wrote:  Lacking looping and subroutines, what was the objective for creating the HP-25/25C?

Seems to me you're asking that (IMHO, pretty dumb) question from a modern perspective, where we've been used to "looping" and "subroutines" for many decades now so a machine lacking both seems (to you) purposeless.

However, I'm older than you and can vividly remember how portable computing was at the time the HP-25 was released back in 1975. At that time, portable RPN compùting was essentially almost nonexistent, with just the unaffordable HP-65 and the very expensive (yet minimally able as far as programming was concerned) HP-55, so your options as an HP, RPN lover wanting decent programmability were next to nil.

Enter the HP-25. Nice size and form factor, many storage registers with arithmetic, all mandatory scientific functions, statistics, *AND* very decent affordable programmability, allowing for quite complex, useful programs, far surpassing what the HP-55 could do, at a much lower price.

Seems you haven't read it (or else you wouldn't be asking that question) but I suggest you have a look at this PDF article, which will make the point crystal-clear:

      Long Live the HP-25 (includes a program which calls a two-variable function f(x,y) four times with different arguments, from four different places, without subroutines)


In short: at the time it was released it was not that the HP-25 lacked "looping" and "subroutines", it was that it HAD everything else !

V.