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The Future of RPN Calculators
Noksagt writes "HP's recent release of the 33s won't be the last RPN calculator. Former HPers at Hydrix are hyping an impressive Linux-based PDA/calculator, named Qonos. They have a survey up regarding features, etc. More information can be found at comp.sys.hp48 or The Museum of HP Calculators.
A new open hardware project called OpenRPN has also begun. Their mission is to produce horizontal and vertical format scientific RPN calcs and later a graphing calc."
maxima.sf.net is a truely awesome symbolic algebra program, it is derived from one of the first ever 'modern' computer algebra systems and was recently made open source.
If it could be put into a calculator, that would rock.
http://notanumber.net/
There's more details and pictures on hpcalc.
Quote:
Operating system:
eCos, running in 512KB SRAM and providing one month of battery life
Linux, running in 64MB of SDRAM and providing considerably more than a day of battery life
Other software:
Emulation of both the HP 49G and the TI-89
Advanced math software: Gnuplot, Giac/Xcas (supposedly better than Maple), MathsExplorer
PDA software: calendar, tasks, notes, time management
Datalogging capabilities
Processor:
Intel PXA 263 XScale processor, running at 400 MHz
32MB of on-chip flash memory
32-bit data bus
Display:
Grayscale 3" 320x240
Full support already exists for a color screen to be offered at a later date
Other hardware:
Mono speaker and microphone
Stereo audio input and ouput ports
Keyboard with tactile feedback designed for fast, accurate data entry
Compact Flash Type II slot
SDIO slot
IrDA port
USB client and host ports, supporting external keyboards, webcams, and other devices
Optional sled:
Vernier probe compatible
8 analog I/O channels
16 digital/sonic I/O channels
Extra high-capacity lithium ion battery
DB-9 serial port
Price:
Over US$350
Hoo-boy. I'm labeling myself as uber-geek.
The reason the 'r' comes and goes is because the 'Q', in Klingon, is sort of like an over done 'k' in English. It's pronounced toward the back of the mouth. The net effect is vaguely like a "kr" sound in English.
So "Kronos" is sort of a phonemic transcription of what "Qo'noS" would sound like.
-- I have monkeys in my pants.
Real geeks want an HP 16C replacement. My 16C's still going, and on only it's 3rd or so set of batteries since 1982. http://www.hpmuseum.org/hp16.htm
Here in the UK, they're forbidden in exams (up to and including university level) and frowned upon as a distraction and hindrance to being able to visual graphs yourself.
That is the chain rule. Sheesh! Doesn't anyone know any mathematics these days. There's more than one type of notation for writing derivatives: f'(g(x))g'(x) is the same thing as df/dg dg/dx.
Doesn't it make you feel good to know that our freedoms are protected by politicans, lawyers and journalists.
Second, you've committed the atrocious sin of mixing Leibniz notation with Newton prime notation. What a horrific mess you've created.
The proper way to write it would be:
h(x) = f(g(x))
h'(x) = f'(g(x))*g'(x)
I think this should help explain why the Leibniz notation is so popular, because in the Newtonian notation, a prime can only bind to a name, not an arbitrary algebraic expression. Hence you are required to introduce the additional function h(x) just to allow the notation to work.
Anyway, you're hardly qualified to school us in calculus.
Reverse Polish notation was invented by an Australian in response to Polish notation, which was invented (gasp!) by a Pole.
The whole story here is
Except OpenRPN isn't trying to be a PDA. It has the hardware to do so (except that the first model will be a small horizontal format, a'la the HP Voyager (11c,12c,15c,16c) series. 1 or 2 lines makes for a difficult PDA. The open nature will likely let people put PDA features on it, but that isn't the goal of the project (though it is the goal of the quonos, which was also mentioned).
That's why you should use variables on the HP48 for that kind of thing...
In school in electrical engineering, I had a huge set of formulas and constants stored in a directory on my HP48GX, all I had to do was to change a constant, then push the right formular onto the stack, press ->NUM once, and had my numeric result (even complex numbers) there, which would have taken at least two sheets of paper by hand.