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HP50G on Emu48 : - 5/0 gives infinity instead of -infinity - Printable Version

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HP50G on Emu48 : - 5/0 gives infinity instead of -infinity - Gil - 12-04-2019 09:38 PM

On my real HP48 calculator, I used to set -22 flag on, and could get an answer to -5/0... a very large NEGATIVE "number".

I use now on my phone the HP50G version of the great Android application EMU48, but dividing with it a negative number by 0 gives "infinity" (i. e. something for me considered as positive according to the visual result) — but not -infinity, as I expect.

What is wrong in my doing (flag settings?) — with HP50G-Emu48 — in order to get the correct sign answer?

Thanks in advance for your clues.

Regards,
Gil


RE: HP50G on Emu48 : - 5/0 gives infinity instead of -infinity - Christoph Giesselink - 12-04-2019 10:25 PM

(12-04-2019 09:38 PM)Gil Wrote:  On my real HP48 calculator, I used to set -22 flag on, and could get an answer to -5/0... a very large NEGATIVE "number".

I use now on my phone the HP50G version of the great Android application EMU48, but dividing with it a negative number by 0 gives "infinity" (i. e. something for me considered as positive according to the visual result) — but not -infinity, as I expect.

What is wrong in my doing (flag settings?) — with HP50G-Emu48 — in order to get the correct sign answer?

Thanks in advance for your clues.

Regards,
Gil

Flag -105 must be set (Approx. mode on) to get the same behavior like on the HP48.


RE: HP50G on Emu48 : - 5/0 gives infinity instead of -infinity - Gil - 12-04-2019 11:24 PM

Actually understood the logic of the HP50G :
it does not know from which side from zero (tiny, but still negative, or just somewhat greater than zero and therfore poditive) I divide my number - 5.

In other words, 'infinite' might mean '+infinite' or '-infinite'.

To get '+infinite' or '-infinite' values,
I have to use 'infinite' EVAL.


RE: HP50G on Emu48 : - 5/0 gives infinity instead of -infinity - Gil - 12-05-2019 05:15 AM

I did not think about it.
I tried your solution setting flag - 105 on and it worked perfectly :
indeed -5/0 gives now, "directly", -infinity.
Thanks a lot.
Gil