&
In laplace,
How to compute differential funtion
example
LAP(d1f(X)) = X*F(X) - f(0)
My English skill is very poor..
I wonder my grammers are right^^;;
Anyway..
help me..ㅠㅜ
This is really odd. Today was the first day I even thought about the
Laplace and Fourier Transforms
on my Hp50g, yet many of the recent messages have been about exactly
this topic. Does this have something to do with a bunch of people
reaching the correct point in the curriculum at the same time?
I have not been able to find any built-in or custom apps to calculate
the Fourier transform as defined by
[LaTeX] X(\omega) = \int _{-\infty}^\infty x(t)\ e^{- i\omega t}\,dt [/
LaTeX] (or even the unitary or ordinary frequency forms, which could
be "corrected" with a simple wrapper.) It also seems like it cannot be
efficently emulated using the LAP function, as that is not a bilateral
laplace transform, which would be needed.
"astrohan" <astr...@naver.com> wrote in message
news:b47baa5d-9d86-4d65...@e10g2000prf.googlegroups.com...
Quite expensive, but very nice packs. Couldn´t be bad coming from
Germany.
HP should provide some of those features built-in or at least make it
downloadable.
Loved Fourier series for piece wise functions. Used to do that with
Mathematica in the old days.
I honestly fear that HP is really no longer in much of a position to
make any more ROM releases. My understanding is that many of the
designers of the software used have left since HP, leaving HP with few
people who could work on the software side of the calculator. But JYA
would probably know better, having been a former HP employee and
Metakernel developer. I do hope I am mistaken.
For what it is worth though, the source code for the CAS (which IIRC
still cause itself Erable in a few places) is available. So
improvements there can still be made.
Further, Bernard Parisse has worked on the CAS since the last official
ROM Release (resulting in the unofficial 2.10 rom series), and may
continue to do so in the future.
In the mean time perhaps somebody can look at laplace.s and create
roughly equivalent Fourier and inverse Fourier commands from it. The
way the transforms work is similar enough that it may be possible.
If somebody does create those commands it might even be possible to
get them integrated into the CAS for the next release, assuming of
course that Bernard Parisse is still working on the CAS.
> I fear that HP is really no longer in much of a position to
> make any more ROM releases. My understanding is that many of the
> designers of the software used have left since HP, leaving HP with
> few people who could work on the software side of the calculator.
A completely ready 2.10 ROM (fixing some outstanding bugs,
plus some previously missed "overlay" locations
for "emulator-accelerated" Saturn code,
and containing updated CAS version 4.20060919)
was in HP's hands, but has never been offered by HP.
Fixes and updates were actually volunteered by the original authors,
even though HP no longer paid them,
through their former associate who remained within HP,
but it appears to have been a management decision
not to release anything further.
-[ ]-
That is worst than I feared. This nearly official rom, how did it
differ from BP's 2.10-7? I would assume there must be some
differences, as a few of the new features in that rom have some semi-
nasty bugs. (IIRC, the spreadsheet had some such bugs, and there was
at least one part of the geometry app with such problems.)
I'm actually still using 2.09. Do you recommend updating to BP's rom?
Also, happen to have any educated guesses why such a Management
decision would have been made? Is HP trying to leave the calculator
business or something?
username@localhost
I suspect that given how calculators are marketed these days (mostly to people
in school), HP figures that an updated ROM is going to have just about zero
impact on their sales so... using modern "marketing guy think," why incur in
the expense of even just sticking it up on a web site?
This behavior seems not dissimilar to what's happening with the HP-35s... In
1972, when HP discovered bugs in the original HP-35, they sent out notices to
all customers offering to replace them. In 2007, when HP (and end users)
discovered bugs in the HP-35s, HP didn't even bother to stick up a web page
documenting those bugs, much less commit to working on bug fixes or offering
replacement machines.
> This nearly official [2.10] rom, how did it differ from BP's 2.10-7?
I would guess that BP may have just updated the CAS part of it
(comparing parts bytewise might test this assumption).
> I would assume there must be some differences,
> as a few of the new features in that rom have some semi-nasty bugs.
> (IIRC, the spreadsheet had some such bugs, and there was
> at least one part of the geometry app with such problems.)
Both the spreadsheet and geometry app reside within the CAS section,
and would of course have been omitted in the non-released HP version.
BP stated that those apps were entirely experimental;
their presence would not affect any programs or operations
not specifically calling upon those apps,
so it would appear that one can get all the benefit
by using BP's version, without otherwise being affected.
> I'm actually still using 2.09. Do you recommend updating to BP's rom?
You can easily re-flash ROM (especially with an SD card),
until one day the flash gives out
(which IIRC no one has ever yet reported),
so it would appear to be risk-free.
> Also, happen to have any educated guesses why
> such a Management decision would have been made?
I am, alas, uneducated -- at least as to what transpires within HP.
> Is HP trying to leave the calculator business or something?
It looks to me as if they are trying to leave the HP50G alone,
and put attention on other product introductions and re-issues
(which may be only "look-alikes," rather than clones of the originals,
given the different results and new bugs which turn up)
[r->] [OFF]
The 'it' there is confusing.
Basically, I'm wondering if BP's rom includes (at a minimum) all the
fixes that would have made it into the official release.
If so, that is excellent.
> > I would assume there must be some differences,
> > as a few of the new features in that rom have some semi-nasty bugs.
> > (IIRC, the spreadsheet had some such bugs, and there was
> > at least one part of the geometry app with such problems.)
>
> Both the spreadsheet and geometry app reside within the CAS section,
> and would of course have been omitted in the non-released HP version.
>
> BP stated that those apps were entirely experimental;
> their presence would not affect any programs or operations
> not specifically calling upon those apps,
> so it would appear that one can get all the benefit
> by using BP's version, without otherwise being affected.
>
It seems quite obvious to me that that the Geometry app would have no
impact unless used, except in the case that including it moved some
unsupported rom pointers that are in use by some 3rd party programs.
(I know there are no 2nd party apps that would break, seeing as I have
not written anything significant in SYSRPL.)
The spreadsheet is not quite as obvious, seeing as it is fairly
closely tied to the matrix editor, although assuming he took some
reasonable precautions (as I expect he did) it should not be a problem
either.
Speaking of installing that rom, I'm having real trouble with BP's ftp
site. Often I cannot connect to the ftp server, but even when i can,
It gives me an error if I try to enter the xcas directory, which is
where the CAS and rom stuff lives.
Is this a general problem? Whats the best alternative source for the
rom?
username@localhost
> Basically, I'm wondering if BP's [2.10] rom includes (at a minimum)
> all the fixes that would have made it into the official [2.10] release
> [if it had been released, which it wasn't]
As I said, I would suspect it to be identical in all non-CAS flash banks,
and updated in the CAS (though I do not know whether anything changed
besides adding Geometry and Spreadsheet functions).
The fact that it identifies itself as "2.10" suggests that it must
have been based on the non-released "standard" 2.10 compilation,
re-linked with a special CAS, but as I did not create this,
I do not know from personal experience.
> It seems quite obvious to me that that the Geometry app would have no
> impact unless used, except in the case that including it moved some
> unsupported rom pointers that are in use by some 3rd party programs.
All external calls to functions in flash banks other than bank zero
are by "flashptr," which is by function number, not an address
(a table within the bank itself converts function numbers to actual
addresses, and is automatically adjusted for each compilation of the bank),
so I wouldn't worry about this, even in the case of software made by
the few people (or one in particular) who like to live dangerously,
using "unstable" bank zero addresses.
> The spreadsheet is not quite as obvious, seeing as it is fairly
> closely tied to the matrix editor, although assuming he took some
> reasonable precautions (as I expect he did)
> it should not be a problem either.
I don't recall ever hearing of any matrix editor problem.
> Speaking of installing that rom, I'm having real trouble.
> Often I cannot connect to the ftp server, but even when i can,
> It gives me an error if I try to enter the xcas directory
At ftp://ftp-fourier.ujf-grenoble.fr/ (with anonymous login)
both my browser and another FTP client show "linux" as a directory (empty),
and all the other entries (including "pub") as "files" (not accessible).
Quel dommage :(
[r->] [OFF]
ftp> open ftp-fourier.ujf-grenoble.fr
Connected to malherbe.ujf-grenoble.fr.
220 (vsFTPd 2.0.5)
User (malherbe.ujf-grenoble.fr:(none)): anonymous
331 Please specify the password.
Password:
230 Login successful.
ftp> dir
200 PORT command successful. Consider using PASV.
150 Here comes the directory listing.
lrwxrwxrwx 1 0 65534 5 Feb 05 12:19 debian -> linux
drwxr-sr-x 2 0 50 4096 Feb 05 12:20 linux
lrwxrwxrwx 1 0 65534 9 Feb 05 12:20 pub -> linux/pub
lrwxrwxrwx 1 0 65534 10 Feb 05 12:20 xcas -> linux/xcas
226 Directory send OK.
ftp: 286 bytes received in 0.02Seconds 17.88Kbytes/sec.
ftp> cd linux
250 Directory successfully changed.
ftp> dir
200 PORT command successful. Consider using PASV.
150 Here comes the directory listing.
226 Directory send OK.
ftp> cd ..
250 Directory successfully changed.
ftp> dir
200 PORT command successful. Consider using PASV.
150 Here comes the directory listing.
lrwxrwxrwx 1 0 65534 5 Feb 05 12:19 debian -> linux
drwxr-sr-x 2 0 50 4096 Feb 05 12:20 linux
lrwxrwxrwx 1 0 65534 9 Feb 05 12:20 pub -> linux/pub
lrwxrwxrwx 1 0 65534 10 Feb 05 12:20 xcas -> linux/xcas
226 Directory send OK.
ftp: 286 bytes received in 0.02Seconds 17.88Kbytes/sec.
ftp> cd xcas
550 Failed to change directory.
ftp> cd pub
550 Failed to change directory.
ftp> bye
.
That matches my experience exactly. Firefox 3 shows 1 directory and 3
symbolic links.
I also did that exact same test with the command line FTP client.
Either all the files
somehow got removed from that ftp server, except the top level folder
and symbolic links, or
somebody over there really messed the server configuration.
Unfortunately, I have not found any mirrors
containing the files, nor do those files look to be available via
http. BP had a few files stored on the http server,
but that was not one of them.
Since Bernard Parisse, would not only know these things better than
anybody else, but might also be interested to know his files
are not available, but has not yet joined the conversation, I am CCing
him.
To Bernard Parisse: apparently your files stored on ftp-fourier.ujf-
grenoble.fr are no longer accessable.
This is a shame, as your 2.10-7 rom is the current latest and
greatest, but is no longer available with the server offline.
Could you look into this? Thanks.
username@localhost
The ftp server had a disk crash, should work again now. I have added a
HTTP mirror for the latest 49/50 ROM
Thanks. Out of curiosity, have you been working more on the hp version
of the CAS recently (in you spare time), or have other projects
grabbed your attention?
Also, Is it just me or is the source code available in CASrelease out
of date? (The more recent fixes not being included).
Oh, yes, a sort-of bug: the lack of help text for Geo causes a problem
with Emac's autocomplete. It seems to think there is CAS help
available, but pushing the button simply causes to calc to hang or
reset.
Correction, it seems that Emac's tab completion attempting to open any
of the CAS help windows causes a crash under 2.10-7. I'm not much of a
fan of that.
Any idea's what the problem is? CD, are you still around? Can you fix
this?
> is the source code available in CASrelease out of date?
> (The more recent fixes not being included).
The object files (all the rest of the ROM, with which
you must link any compiled CAS) are way out of date, too,
so any ROM which you make yourself from that specific "kit,"
even if you have completely new CAS source,
is as of a very old ROM in all other parts.
It's therefore a bit difficult for anyone
to make a personal, up-to-date, complete ROM at home,
except for those who possess the entire source
and the entire system which produces ROMs.
One might be able to break apart a more recent ROM
to get the other "object" ("vger") parts, but you would also
need to have the updated complete list
of both supported (unchanging) and non-supported ROM addresses,
or else a newly "linked" CAS part might not work with it.
Come to think of it, "casrelease" is as of ROM 1.24
for the original HP49G -- I think you can not even create
a ROM for the 49G+/50G series from it, although it does
also output a ROM suitable for the emulator (emu48/49).
Another sort of "Catch-22" -- you can have it,
but you can't do much with it:
http://en.wikipedia.org/wiki/Catch-22
http://en.wikipedia.org/wiki/Catch-22_(logic)
http://www.imdb.com/title/tt0065528/ [film]
http://www.amazon.com/Catch-22-Joseph-Heller/dp/0684833395
http://www.bookrags.com/notes/c22/
http://www.nytimes.com/books/98/02/15/home/heller.html
[r->] [OFF]
That's correct. I do not have the right to update object files for the
casrelease myself. And that would be only helpfull for the 49G anyway
(patient people may wait until the copyright expires, then we will be
able to publish the whole source code...). The main purpose of the
release of the CAS under the GPL was for me to be sure not to have any
problems with giac/xcas (I don't think I would have had problems since
the languages are different, but it's better to be sure).