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Do you still use stand-alone ("pocket") calculators?
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Mortymore:
Results for Integral of ln(x^2)dx, from -5 to 99

We can add:

Casio FX-991ES PLUS -------- 2m56s -------------- 717.9281095
Casio FX-991W ---------------  1m28s -------------- 718
Casio FX-991EX ---------------- 35s ----------------- 717.9281095
Casio FX-570SPX II ----------- 35s ----------------- 717.9281095
HP 48G -------------------------- 53m40s ------------ 717.928325369
HP 39GS ------------------------ 20m28s ------------ 717.928325369 (EDIT)

Notes:
My FX-991ES shows ROM 018. Given we were recording the 991ES vs 991ES PLUS, that would explain the difference. On the path of evolution we have, 991ES: 3m15 > 991ES PLUS: 2m56s > 991EX: 35s
My HP48G is currently running (39 minutes and counting), with only FLAGs 02 and 03 set
emece67:
.
iMo:
I flashed my wp-34s 5-6y back. Is there any new binary somewhere available, plz?
PS: here are the latest binaries it seems.
And the repo with the sources.
SiliconWizard:

--- Quote from: Mortymore on January 19, 2020, 12:03:23 am ---Integral of ln(x^2)dx, from -5 to 99

--- End quote ---

Success with this integral and the time it takes will completely depend on the method used.

If you have an HP prime, looks like the fastest would be to do this in CAS mode (which will give you the exact result almost instantly). Then you can copy it in home mode to get the approximate value.
The Prime uses Giac for its CAS AFAIK, which you can also use on computers. https://www-fourier.ujf-grenoble.fr/~parisse/giac.html
(There is a web version if you want to quickly test it: https://www-fourier.ujf-grenoble.fr/~parisse/xcasen.html )

integrate(ln(x^2),x,-5,99)
will give you:  5ln(25)+198ln(99)-208≈717.928109451

I tried with Maxima (both symbolic with integrate() and numeric integration with romberg(), and both failed.)
Also tried with Yacas ( http://www.yacas.org/ ), that I rarely use. Contrary to xcas/giac, it fails to solve the symbolic integration (with: Integrate(x,-5,99) Ln(x^2) ), but manages the numeric integration (with: NIntegrate(x,-5,99) Ln(x^2) ), it takes several seconds though, and is not very accurate (gives 717.92810937).
rsjsouza:
I can't resist these posts. I love "physical calculators".

I like the mechanical memory of the calculators I have, as well as the extended precision of the HP35 and HP48 for those bit and base conversions.

A bit of my history on one of the previous threads:


--- Quote from: rsjsouza on August 11, 2019, 10:23:34 pm ---I also replied to Ampera's old thread as well. My heart belongs to many models, and I am faithful to all of them! :D

My favourite is the HP48 - I got a 48SX in 1991 but about 20 years later it simply died. My wife then kindly gave me her 48GX which is still alive and well. At work I have a HP35S that does an excellent job for me (too afraid to leave the 48GX there and have it "borrowed" by someone that does not intend to return it).

I started with my dad's TI-59 (first thing I ever programmed) and I currently have a TI-66 just to flex my programming muscle memory. I love both, although the 59 still holds a special place in my heart.

My first actual calculator was a Casio fx-39 given to me by my dad in 1982. I still have it, along with my brother's and another one I got a few years ago in the hopes to get it working again. Unfortunately the Casios of the time had a very bad keyboard resistive mat that becomes brittle and ceases to work after a few years...

(edit) oh, and I forgot a HP11C that I got a few years back on the local market with the intention to turn a profit. Something about the Voyager calculators (TI66 as well) made me fall in love with it. Never sold it and currently don't plan to do it.

--- End quote ---
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