comp.sys.hp48 Google Group

Re: U of H calculator contest

2009-11-28T06:23:59Z

Ok, I missed (or didn't try, in the case of #20), 7 out of 20. I feel
good that I made the same mistake as wes on #8 and #17,
but I made stupid errors on some of the others.
Obviously, it is very doubtful that I will ever get into the
University of Houston.
But help me here, get an education. On number 12, I wrote a recursive

StreamSmart

2009-11-28T04:39:26Z

Has anyone heard anything more about a version of StreamSmart
compatible with the HP50g as well as the 39/40?
Also has anyone heard anything about whether Vernier sensors will be
usable with an adapter.
I have had discussions with various member of my department about
getting one to test out. However they are not willing to go beyond

Re: Matrix operations in SysRPL

2009-11-28T01:08:23Z

Thanks! Good to know that:-)
Regards,
Gurveer

Re: Matrix operations in SysRPL

2009-11-27T23:03:04Z

UserRPL has only a _per-command_ overhead for some protection
(argument validation) and housekeeping (command name,
argument and stack depth saving for errors and for LASTARG).
The internal functions are not going to make themselves
any faster when called from a user command
then when directly called instead of the user command.

Re: Matrix operations in SysRPL

2009-11-27T21:53:03Z

I was going through some other posts too and wondered if overclocking
could prove to be of any help.
Any idea?
Regards,
Gurveer

Re: U of H calculator contest

2009-11-27T18:54:16Z

I don't believe that it is either of these two choices. I didn't
think it was so unclear. The woman knows what everyone else has
chosen. Given all the ways that everyone else chosen numbers which
meet the requirements, what is the probability that she CAN choose a
number that meets her special requirements. It is not 100%. If the

Re: U of H calculator contest

2009-11-27T15:09:23Z

Concerning Question #20
The more I look at this problem, the more confused I am about what
it's even asking. After the setup, the actual question is: "What is
the probability that she can choose a composite number in the set {2,
3, ... , 100} that is larger than any of the numbers chosen by the
women and forces the sum of all chosen numbers to be an integer

entry point EDITPARTS

2009-11-27T14:58:40Z

I dissembled this entry (see below) and cannot understand why there is
a call to =firstchar that simply gets overwritten with the number of
carriage returns upon reading from =EditParts. Can anyone explain
this? (SNIB9 is a nibble that determines whether or not we are in edit
mode.)
****************************** ****************************** *********

Re: Matrix operations in SysRPL

2009-11-27T07:04:58Z

Hi,
usually the UserRPL functions dispatch to SysRPL code,
and the core matrix access functions are coded in ML anyway,
so if you don't want to do real-time graphics,
there's not much to be gained IMHO;-)
HTH
Raymond

Matrix operations in SysRPL

2009-11-27T06:08:26Z

Hi
Performing some matrix calculations in System RPL, I didn't find a big
time difference as compared to User RPL. Can they somehow be made
faster in SysRPL? I only deal with real matrices and of order atmost
10 X 10(rarely, usually around 4). The basic operations I use are /,
*, +, -, inverse, transpose, etc. to do some stuff related to complete

Re: U of H calculator contest

2009-11-26T16:03:18Z

Yep, I hit SigmaList instead of PiList. I hate it when I make the
silly mistakes that I warn my students against. :-)
s -> r*s*(1-s), r=3, initial s=0.5
When I took the test, I thought we might be looking at a place where
the function had a periodicity of 2, but if you make a bifurcation
plot, you see that r=3 is right where the plot bifurcates, so s_n

Re: Few question about gradient/deriv and saving a vector function...

2009-11-26T08:54:42Z

Hi vexx, in RPN mode:
\<< [ 'X' 'Y' 'Z' ] DERIV EXPAND \>> 'GRADIENT' STO
'P(X,Y,Z)=X^2+Y^2+Z^2' DEF
'P(X,Y,Z)' GRADIENT --> [ '2*X' '2*Y' '2*Z' ]
\<< \-> X Y Z \<< '2*X' EVAL '2*Y' EVAL '2*Z' EVAL \>> \>> 'O' STO
ex. 2 3 4 O --> 4 6 8
supergems

Re: U of H calculator contest

2009-11-25T23:09:33Z

By the way, that's exactly the way I wrote the answer on my answer
sheet.
Scott

Re: U of H calculator contest

2009-11-25T22:58:30Z

[snip]
I didn't think they needed to be consecutive either. I did it in
three hours in Mathematica. My anwer was 0.0286152273889, and took
only a few seconds to calculate. (I have an exact fraction, also.) I
checked my method with a Monte Carlo implementation, too. Before I
got both my Mathematica and Monte Carlo code debugged, I had to do the

Few question about gradient/deriv and saving a vector function...

2009-11-25T22:46:25Z

Lets say that I have defined some simple scalar function for example:
DEFINE('P(X,Y,Z)=X^2+Y^2+Z^2')
NOVAL
Then I stored a simple vector:
[X,Y,Z]|>J
[X Y Z]
If I want do calculate gradient of my scalar function the manual states:
DERIV(X^2+Y^2+Z^2,[X,Y,Z])
[2X 2Y 2Z]
If I use:
DERIVE('P(X,Y,Z),[X,Y,Z]')