Integration question and "RPN" mode comment


Hi all;

On my Prime, in Function, with CAS selected, diff(LN(x)) yields 1/x
but int(1/x) gives plus or minus infinity or Error, depending on CAS settings.

I'm sure I just have the settings wrong but haven't figured it out yet. Help!

Sorry for such an elementary question but there it is. :-)

Also, I've owned probably a dozen RPN HP's over the years with the last one I purchased being an HP48. Conventional RPN actions are very firmly trained in.

HP guys: Please consider a change like so...if a user selects RPN entry mode and operates in "Home", why not treat registers 1 and 2 as if they were the old-style x and Y registers and having the x to the y key act on these, and the nth root key using the "y" register for n to operate on the number in the "x" register, you would gain gratitude (and business) of existing engineers.

Home mode in RPN would be just about completely familiar to legions of engineers with thousands of aging HP's. College math students would not even notice the change.

Failing that, how about putting out an HP42S limited edition, for engineers? I bought a pair of 15c's and would do the same with an HP42S.


For consideration:!topic/comp.sys.hp48/khD4M5M0wrU

A quote from one of my posts in that thread:

x^y was used in previous HP calculators as was said and doesn't have anything to do with the old XYZT stack. It is just a pure power operator. As has been discovered, it calculates just like on the 50g. True, it could have just been labeled ^ but personally I think that is kind of ugly and less clear to both the math experienced and the math inept.

One consideration that has not been discussed though is that y^x would not fit well on the key without messing up the vertical alignment. The 50g doesn't have "classic HP style" sloped fronts on the keys - nor does it try to fit everything onto the same key. With the sloped front key, you can't print over the boundary there for many reasons. The "tail" of the y would require either reducing the y height, shifting the whole assembly upwards, reducing the size or something like that in order to avoid encroaching into the sloped front of the key.

Summing up, x and y mean nothing with respect to stack and it behaves identically to the 48. Changing the order to match the printing would annoy far more people then it would make happy.


Edited: 2 Dec 2013, 11:36 a.m.


Thanks for your reply.

So, the Prime is 'not' an engineering calculator but a math machine.

Making "RPN" mode only, act more like legacy HP's...I can't see it as the problem you do.

Thanks anyway.


IMHO the HP Prime is certainly more geared more towards being a student math learning machine, similar to the TI Nspire series it is competing with. It is not really a direct replacement for the HP-50G. This makes sense given that the market for student math learning calculators is vastly larger (a huge understatement) than the market for engineering calculators.

Unlike the TI Nspire series, the Prime has direct keys for SIN, COS, TAN, is less cluttered and is "friendlier" for use as an engineering calculator too. It also supports RPN (really RPL) in Home mode so we die-hard RPN/RPL users (a dying breed, to be sure) can use it too. The decision to include RPN was probably an uphill battle by Tim and Cyrille over management's wishes and I thank them very much for doing it :)

The bottom line is that the HP-50G or (HP-35S) is probably a better choice for someone who wants a RPN/RPL engineering calculator, at least at this point in time.


The bottom line is that the HP-50G or (HP-35S) is probably a better choice for someone who wants a RPN/RPL engineering calculator, at least at this point in time.

I might agree on the HP-50G (for future battleship commanders), but for the friends of lightweight, agile, compact pocket (!) calculators I'd recommend the WP 34S - it runs circles around the HP-35S IMHO. I may be a bit biased though.


Edited: 2 Dec 2013, 3:24 p.m.


I actually have an HP35S. It is the HP calc I use the least. Not at all. :-)

If they ever decide to produce another "engineering" calc, perhaps they'll run the early designs past working engineers...or even do a new run of HP42S units.

If I understand correctly, they sold all the HP 15C limited edition units. I bought two. Other "limited editions", carefully chosen, would probably do as well.


Well I don't know if the "they" you refer to has to be Hewlett-Packard--but the WP 34S Walter is trying to tell you about is the very definition of "design [run] past working engineers."

WP 34S Scientific Calculator


I am tempted. Is there work on a follow-on device as well? I came across a few posts implying this.



Is there work on a follow-on device as well?

Yes, there is - but don't hold your breath, it will probably take many (!) months. So you better get your WP 34S now.




or even do a new run of HP42S units.

I agree - I'd buy a couple to supplement my three original units and EMU42 and Free 42.

The 42S had an elegance that is missing in todays, do-it-all, put it up-front on the keys, overload the keys so that my eyes swim, etc., calculators.

For me, the 42s has 90% of what I need direct on the keys. I can live with 10% buried in extra keystrokes. Even though I am an engineer, I guess my requirements are minimum compared with others here.

Of course I am old-school - I still use lots of single-use DOS programs daily in my work. Give me a simple, elegant tool, that does a fairly simple function really well and I am a happy person. Give me a tool with a 400-600 page manual that tries to do everything and I probably will get frustrated long before I learn how to use it. I most likely will abandon it.

To each his own.



You bought three Hp42s?

I wish I had.


I agree on the HP-42S (and the HP-27S) being the most elegant scientific calculators built.

Nevertheless, the majority of forumers prefer the HP-32SII to the HP-32. That vote and the display limitations caused the WP 34S having three shift keys.



Hi Walter,

Nevertheless, the majority of forumers

I always shudder when I see these types of statements. Since I do not know exactly how many registered or even active (though silent) users there are to the forum, it would be difficult for myself to ever proclaim what a majority of them think or would vote on.

I could say what a majority of those that took the time to express an opinion voted on. But I definitely could not say what a majority of the forum members thought on anything.

Please note that I think the WP-34s is an amazing piece of work and shows what can be obtained by a dedicated group. But it's not my cup of tea.



Hi Bill,

Point taken. I should have written: "The majority of forumers who voted ...". Precise people here.



Precise people here

Well, we do discuss precision here a lot




Please modify your title in order to mention a 'Prime' subject.


Another vote for sticking "HP-Prime" in thread titles on that topic -- some of us come here to read about other issues than bug tracking for the next Prime firmware.


Edited: 5 Dec 2013, 2:48 a.m.

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