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I’d like to take the opportunity to recommend the HP Prime G2 (for those of you who, like myself, appreciate the flexibility of a reasonably-powered CAS) and th

by qubex 6y ago

I’d like to take the opportunity to recommend the HP Prime G2 (for those of you who, like myself, appreciate the flexibility of a reasonably-powered CAS) and the NumWorks (which, when loaded with the Omega fork of the open-source Epsilon firmware) provides excellent functionality in very minimalist package and even supports CAS (through the easy installation of khiCAS).

nsajko 6y ago
I also wanted to point to Numworks as an alternative calculator. It uses a 216 MHz ARMv7-M Cortex-M7 microcontroller and is almost open-source (both the hardware and the software, called Epsilon). https://www.numworks.com/resources/engineering/ https://www.numworks.com/resources/engineering/ There was (and probably still is) a Numworks pet peeve of mine, though. As far as I understand, on many kinds of calculations (e.g., calculating a power of a number, or a derivative at a point) the Numworks software does an artificial "rounding" step with the purpose of presenting "nicer" results to high-schoolers in trivial cases. See https://github.com/numworks/epsilon/pull/1376 https://github.com/numworks/epsilon/pull/1376 and https://github.com/numworks/epsilon/issues/1373 https://github.com/numworks/epsilon/issues/1373 . It seems like the Numworks dudes have no concept of the accumulation of rounding errors :( ? On top of removing precision intentionally being a weird choice, the implementation is too naive as far as I understand. This is basically what they do: result = std::round(result / error) * error See, e.g., https://github.com/numworks/epsilon/blob/c92b770112e38bd906ae2467d89e0e3cd02ec10b/poincare/src/derivative.cpp#L80 https://github.com/numworks/epsilon/blob/c92b770112e38bd906a... Would it not be both faster and less destructive to numerical accuracy to just clear some least significant IEEE 754 bits? EDIT: forgot to mention it is approved for the SAT and ACT already. EDIT2: More relevant to this thread; one can not run assembly on the Numworks written from the Numworks (it would be hard to fit all the prerequisites on its RAM and/or flash, e.g. Epsilon does not even have a file system), but it is possible to write C++, C, or assembly on your Linux or Windows PC, compile it and push it to the Numworks.
boricj 6y ago
I'm a contributor to Epsilon and Omega. It's too early to guess how much of a backlash this will generate, but calculator forums are extremely pissed right now. TI completely destroyed any goodwill they had remaining at this point. I'm not sure how this will unfold, but they've pissed off a fair number of smart people that know their calculators inside and out. I expect jailbreaks, boycotts and people switching to other platforms fairly quickly.
- qubex 6y ago
  I find the NumWorks to be a lovely little calculator but Omega really needs to provide some serious symbolic (i.e. ‘CAS’) functionality. It’s all fair and square that the official Epsilon firmware doesn’t feature CAS to appease the examination boards, but it’s a feature that is pretty key for a more sophisticated crowd. No algebraic computation? No symbolic differentiation and integration?! That’s really quite disappointing.
  - boricj 6y ago
    There is support for giac as an external app, the port is named KhiCAS. Flash a firmware with external app support (Omega typically) and then use https://zardam.github.io/nw-external-apps/ https://zardam.github.io/nw-external-apps/ to transfer apps. Right now the current external app system is a glorified proof-of-concept when compared to the TI/Casio ecosystem, but it does work. One cannot distribute epsilon with giac integrated since their licenses are incompatible (GPL3 vs CC-BY-NC-SA), hence the external app workaround. NumWorks could negotiate a commercial license, but there has been no sign of this so far.
int_19h 6y ago
Does Prime support native apps with standard firmware?
- qubex 6y ago
  No.
  - int_19h 6y ago
    Hm, so what are the remaining calculators that do? I thought HP 50g would be one, but apparently it's already discontinued. Casio still makes their Prizm series - there's no docs or official native SDK for it, but community cobbled something together, and they don't proactively block it. Is that it?

by qubex 6y ago

nsajko 6y ago

I also wanted to point to Numworks as an alternative calculator. It uses a 216 MHz ARMv7-M Cortex-M7 microcontroller and is almost open-source (both the hardware and the software, called Epsilon). https://www.numworks.com/resources/engineering/ https://www.numworks.com/resources/engineering/ There was (and probably still is) a Numworks pet peeve of mine, though. As far as I understand, on many kinds of calculations (e.g., calculating a power of a number, or a derivative at a point) the Numworks software does an artificial "rounding" step with the purpose of presenting "nicer" results to high-schoolers in trivial cases. See https://github.com/numworks/epsilon/pull/1376 https://github.com/numworks/epsilon/pull/1376 and https://github.com/numworks/epsilon/issues/1373 https://github.com/numworks/epsilon/issues/1373 . It seems like the Numworks dudes have no concept of the accumulation of rounding errors :( ? On top of removing precision intentionally being a weird choice, the implementation is too naive as far as I understand. This is basically what they do: result = std::round(result / error) * error See, e.g., https://github.com/numworks/epsilon/blob/c92b770112e38bd906ae2467d89e0e3cd02ec10b/poincare/src/derivative.cpp#L80 https://github.com/numworks/epsilon/blob/c92b770112e38bd906a... Would it not be both faster and less destructive to numerical accuracy to just clear some least significant IEEE 754 bits? EDIT: forgot to mention it is approved for the SAT and ACT already. EDIT2: More relevant to this thread; one can not run assembly on the Numworks written from the Numworks (it would be hard to fit all the prerequisites on its RAM and/or flash, e.g. Epsilon does not even have a file system), but it is possible to write C++, C, or assembly on your Linux or Windows PC, compile it and push it to the Numworks.

boricj 6y ago

I'm a contributor to Epsilon and Omega. It's too early to guess how much of a backlash this will generate, but calculator forums are extremely pissed right now. TI completely destroyed any goodwill they had remaining at this point. I'm not sure how this will unfold, but they've pissed off a fair number of smart people that know their calculators inside and out. I expect jailbreaks, boycotts and people switching to other platforms fairly quickly.

qubex 6y ago
I find the NumWorks to be a lovely little calculator but Omega really needs to provide some serious symbolic (i.e. ‘CAS’) functionality. It’s all fair and square that the official Epsilon firmware doesn’t feature CAS to appease the examination boards, but it’s a feature that is pretty key for a more sophisticated crowd. No algebraic computation? No symbolic differentiation and integration?! That’s really quite disappointing.
- boricj 6y ago
  There is support for giac as an external app, the port is named KhiCAS. Flash a firmware with external app support (Omega typically) and then use https://zardam.github.io/nw-external-apps/ https://zardam.github.io/nw-external-apps/ to transfer apps. Right now the current external app system is a glorified proof-of-concept when compared to the TI/Casio ecosystem, but it does work. One cannot distribute epsilon with giac integrated since their licenses are incompatible (GPL3 vs CC-BY-NC-SA), hence the external app workaround. NumWorks could negotiate a commercial license, but there has been no sign of this so far.

int_19h 6y ago

Does Prime support native apps with standard firmware?

qubex 6y ago
No.
- int_19h 6y ago
  Hm, so what are the remaining calculators that do? I thought HP 50g would be one, but apparently it's already discontinued. Casio still makes their Prizm series - there's no docs or official native SDK for it, but community cobbled something together, and they don't proactively block it. Is that it?