12C vs 12C Platinum Cash Flows

[Katie Wasserman]

In looking through the 12C, 12C Platinum and the New 12C Platinum manuals I see that cash flow processing has been increased. The original 12C allows for 21 cash flows, the 12C Platinum allows for 31 cash flows and the New version allows for 81 cash flows.

But the Error section of the manuals for the 12C Platinum say that Error 6 will be returned if you attempt to set N0 (the number of cash flow in the initial cash flow register). This contradicts what an earlier section of the manual implies and is different from the original 12C. I don't have either Platinum calculator to try this out on, but would like to know what the true situation is.

(Why do I care about this? I'm playing around with various sorting and median calculations that make use of the Nj registers and the algorithms need to use N0.)

[Don Shepherd]

Katie, they didn't lie! I don't have the "new" 12c platinum, but the "old" platinum does behave that way. You cannot set n(0) to a value between 2 and 99, like you can on the original 12c. Kinpo strikes again!

[Gene Wright]

Katie is correct.

The original 12c platinum would not allow for a value input for N0 and the 12c platinum manual was adjusted to tell users to not do this (which was a change from the black/gold 12c).

When the new 12c platinum was coming out (the one with parentheses) and the manual was being edited to put in algebraic examples everywhere, it became apparent that on the newest 12c platinum, the prohibition against having a value for N0 no longer applied. I convinced Cyrille to allow that language in the body of the manual to be changed to its present state.

Sadly, the change needed in the error section notation of the Error 6 slipped past me. :-( That's the first mistake that's been brought to my attention in the manual.)

In summary:

original 12c : N0 can be used
original 12cp: N0 cannot be used
newest 12cp: N0 can be used again.

So, thanks for finding it and keep looking!

(Interestingly, Tony Hutchins was instrumental in correcting most of the error section of the manual. Many of these had been wrong since the ORIGINAL 12c manual back in 1981. If you compare the error sections of the 12c manual and the newest 12cp manual, you'll see the differences. Where there are differences, it will be the newest 12cp manual that is in almost all cases correct!)

Gene

[Katie Wasserman]

Gene,

Thanks for alleviating my confusion over this. Sorry about the error section mistake, but you did a great job on the manual! I'm glad to see the additional 50 cash flow registers in the new 12cp and that I can use N0. I better go and buy myself one of these so that I can do some serious programming on it :)

-Katie

[Gene Wright]

No, no Katie!

It is never ! a problem to find mistakes. That means they can be corrected when a chance arises. :-)

And, yes, please develop some good programs for the 12cp. I particularly like Tony Hutchins good games for the 12cp. :-)

Gene

[Namir]

Gene,

Do you know of any online store that sells the NEW version of the HP-12CP??? It has been very frustrating to find one. All the storesthat carry HP calclators in my area do not carry the 12CP. I know buying online can be tricky in this case. My wife who buys TI/HP/Casio calculators for a local university bookstore was unable to get me a new 12CP. She called her suppliers and they were too lazy to go look for one that is a new version.

Namir

[tony (nz)]

Quote:

---

Gene,

Do you know of any online store that sells the NEW version of the HP-12CP???

---

I am delighted to see that:

www.educalc.net

have a front page link to the *new* hp12cpt.

They are based in Singapore & excellent to do business with.

I see they now also have a message board.

Cheers,
Tony

[GE]

They also carry the "new" HP8s. Does anyone have any info on this one ? At $12 one can't expect major miracles.

[tony (nz)]

Quote:

---

They also carry the "new" HP8s. Does anyone have any info on this one ? At $12 one can't expect major miracles.

---

It's being launched in SE Asia on 1/1/2006. Picture of box:

http://www.educalc.net/181086.page

There is a lot of detailed info about it at www.educalc.net.

Cheers,
Tony

[tony (nz)]

Gene, I totally missed that Nj behaviour - till I was writing a little article a month or so ago. Till then I didn't even realise we could have a variable N0 - I was mislead by the formulae in Appendix D for NPV and IRR - the NPV formula there is only valid for all Nj=1, and the IRR formula is only valid for N0=1 - the +CF0 term should be generalised.

You can even have N0=0 - useful if you want NPV and IRR to ignore R0 (a.k.a. CF0).

Katie, thanks for spotting that superfluous last phrase under Error 6! I look forward to your programs. Hope you can find the new 12cpt - I can report that the keyboard is greatly improved. At work I even switch to ALG so visitors to my desk can use it - much easier than explaining about RPN :-)

Cheers,
Tony

Edited: 27 Dec 2005, 4:19 p.m.

[tony (nz)]

Quote:

---

(Why do I care about this? I'm playing around with various sorting and median calculations that make use of the Nj registers and the algorithms need to use N0.)

---

One undocumented improvement on the new 12cpt is that [g][CFj] does *not* change the associated Nj. This can make correcting cashflows less stressful. I'd often forget about Nj, assuming it would be unchanged, but on the 12C gold it got reset back to 1.

[g][CFo] does however still always reset the Ro to 1.

It never got documented because the examples in the manual don't really touch on this (he says hurriedly re-scanning the manual<G>)- it's only really evident for j>19 as then one cannot just use [STO] to alter a cashflow. On the 12C gold all cashflows can be manually altered without affecting Nj, by using a direct [STO].

CLEAR REG (non-programmable) resets all Nj=1 on the new 12cpt.

Looking forward to your median program :-)

Cheers,
Tony