Question about GSL

[douganc]

Hi All,

Do you know if the Gnu Scientific Library is incorporated into XCAS / HP Prime Software ??
If not, will it be incorporated into XCAS / Prime in a future release. ?

Thank You for your help.

Colm

[Tim Wessman]

(09-03-2015 09:08 AM)douganc Wrote:  Do you know if the Gnu Scientific Library is incorporated into XCAS / HP Prime Software ??
If not, will it be incorporated into XCAS / Prime in a future release. ?

Thank You for your help.

While I cannot completely discount this, there are two major reasons I can see that would be nearly impossible to overcome at this time.

1. Licensing - since it uses GPL, the entire calculator software would then fall under the GPL. Since there are components in there for which HP is only licensing from others that would eliminate the possibility at this time. HP cannot re-license and release those components as source since we do not own the copywrite.

2. Size - while I am not certain the total size of the whole suite, I really suspect it is much too large to put on Prime. Currently, there is a limit of 32MB since the binary resides in RAM while executing. Every bit of space you can reduce that means more space for the end user.

[douganc]

Ok, thank you for your reply.

Colm

[parisse]

GSL is linked inside Xcas, but not inside the Prime for the reasons exposed by Tim. It was an important component of Xcas in the past, but it is not used frequently now because I replaced most GSL calls with my own code. The same is true for other GPL libraries used inside Xcas. They remain useful for very specialized fields, for example PARI for elliptic curves, or lapack/atlas for matrices of size greater than 1000, all kinds of things you will probably never do on a calculator.

[douganc]

When you say linked inside XCAS, do you mean ,If the GSL is installed on the system, XCAS will find it and use it. ?

[matthiaspaul]

(09-03-2015 02:44 PM)Tim Wessman Wrote:  1. Licensing - since it uses GPL, the entire calculator software would then fall under the GPL. Since there are components in there for which HP is only licensing from others that would eliminate the possibility at this time. HP cannot re-license and release those components as source since we do not own the copywrite.

As a sidenote, this implies that HP is incorporating Xcas into the Prime under a dual-licensing scheme, not under the GPL 3, right? Because if it were licensed under the GPL, the inclusion of another GPL-licensed package like GSL shouldn't make a difference in regard to the question if or if not sources of these components can or must be published.

Greetings,

Matthias

[Tim Wessman]

(09-03-2015 10:43 PM)matthiaspaul Wrote:  As a sidenote, this implies that HP is incorporating Xcas into the Prime under a dual-licensing scheme, not under the GPL 3, right?

Correct.

[parisse]

(09-03-2015 09:55 PM)douganc Wrote:  When you say linked inside XCAS, do you mean ,If the GSL is installed on the system, XCAS will find it and use it. ?

No, it is linked at compilation, sometimes statically (windows for example), sometimes dynamically (linux).

[Paul Dale]

(09-03-2015 02:44 PM)Tim Wessman Wrote:  2. Size - while I am not certain the total size of the whole suite, I really suspect it is much too large to put on Prime. Currently, there is a limit of 32MB since the binary resides in RAM while executing. Every bit of space you can reduce that means more space for the end user.

Is there any physical reason you can't execute in the place the code? I'm not overly familiar with the prime architecture but I've done more than a bit getting code to run from flash (m68k no-mmu execute in place shared libraries which made it into gcc).

- Pauli

[Claudio L.]

(09-04-2015 06:57 AM)Paul Dale Wrote:  Is there any physical reason you can't execute in the place the code? I'm not overly familiar with the prime architecture but I've done more than a bit getting code to run from flash (m68k no-mmu execute in place shared libraries which made it into gcc).

- Pauli

From a post in another forum, the flash seems to be a NAND (K9F2G08U0C from Samsung), and therefore appears to the CPU as a block device connected to the NAND controller in the CPU, not as an actual memory bank connected to the Memory Controller. While there's usually a 4 kbyte window of SRAM that could be used to execute code without using the main RAM (as far as I know it's used only to bootstrap bootloaders), all you can do with NAND is read/write blocks like a disk device.

[debrouxl]

Correct. XIP works with NOR Flash memory, but not with NAND Flash memory.
The sad thing is that for Flash, NAND technology is denser than NOR technology, so most NOR Flash memories are only several kilobytes to several megabytes.
Multiple older calculator series use NOR chips, but the higher-end models with more persistent storage space, at least the whole TI-Nspire series and the Prime (not sure about the Casio fx-CP400, but both the hardware and software of that PoS are limited, despite the very high price tag, so few people care), are equipped with NAND chips.