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17bii Let and Get L() and G()
Message #1 Posted by bill platt on 23 Feb 2004, 6:14 p.m.

Hello to all,

L(x, alg) on the 17bii

Can someone steer me towards this business? I seem to remember something about it--but cannot find what I am looking for.

I just recently bought a 17bii.

It's a pretty nice machine. But there are two quirks:

1. Why not just squeeze sin cos tan in there! (I guess that is what the 27s was for---but no RPN there!)

2. What's with the ridiculous no precedence in the "algebraic" entry?!!! Inside the solver, the interpreter treats expressions with proper precedence. But out on "the calculator line" it is all goofed up. It's too bad, because algebraic with precedence even mimic the old adding machinge logic in key sequencing. But with the no precedence thing, you have to add a parenthesis around factors---thatis all bass ackwards! Sheesh.

Fortunately, the machine has RPN. Thank god, or it would be a disaster. Cause the rest of it is really very nice.

Regards,

Bill

      
Re: 17bii Let and Get L() and G()
Message #2 Posted by hugh steers on 23 Feb 2004, 6:26 p.m.,
in response to message #1 by bill platt

hi bill,

my exact thoughts. i very much like the 17bii, its a very good pick up and use machine for non-scientific operations. but hey they could have been on a menu. they are (i think) for the 19bii.

as for precedence, its lame. the 10b is the same, but theres no rpn to fall back on either. which is bad.

i havent figured L & G either, can someone explain? it was only when i got hold of the 19bii that i fully appreciated the programming power of both machines. the 17bii is the same, but rather more difficult to program (the alpha entry). the solver is awsome though. the whole language is based upon it and its almost like another programming universe.

also, does anyone know if the currency symbols on the 19bii can be customised (eg to add euros?).

best wishes,

            
Re: 17bii Let and Get L() and G()
Message #3 Posted by Jan (CH) on 24 Feb 2004, 7:45 a.m.,
in response to message #2 by hugh steers

This may help you

http://www.palmtoppaper.com/PTPHTML/3/ptp3005a.htm

Regards

Jan

                  
Re: 17bii Let and Get L() and G()
Message #4 Posted by bill platt (les Estats Unis d'Amerique) on 24 Feb 2004, 9:15 a.m.,
in response to message #3 by Jan (CH)

Hi Jan,

Yes, I've see that. I tried it on the 17bii and I get "invalid equation."

Perhaps Let and Get do not apply to the 17bii. They are not documented in the manual, but I was sure I had heard someone discussing them as "undocumented features"

regards,

Bill

                        
Re: 17bii Let and Get L() and G()
Message #5 Posted by Barry M on 24 Feb 2004, 5:57 p.m.,
in response to message #4 by bill platt (les Estats Unis d'Amerique)

The 17BII can make extensive use of both the L() and G() functions. As an example, see the following solution to solve for the put or call price of an option using the Black-Scholes option pricing model:

http://h20015.www2.hp.com/en/document.jhtml?reg=&plc=&lc=en&cc=us&prodId=hp17biifin81577&docName=bpia5179&cat=use

I use this very equation in my 17BII for option pricing problems. I also have several other equations that use both L() and G(), such as a "modified" TVM equation that emulates the results of the venerable 12C for odd-period calculations (the built-in TVM model in the 17BII does not appropriately handle problems that have an odd first period).

Hope that helps.

Barry

                              
17bii Let and Get L() and G(): Thanks Barry!
Message #6 Posted by bill platt on 25 Feb 2004, 12:46 p.m.,
in response to message #5 by Barry M

Very interesting--exactly what I was looking for!

Regards,

bill

                        
Re: 17bii Let and Get L() and G()
Message #7 Posted by Jan (CH) on 24 Feb 2004, 6:11 p.m.,
in response to message #4 by bill platt (les Estats Unis d'Amerique)

L( ) and G( ) work on my 19BII, so they should work on 17BII as well. To resolve the problem "invalid equation" try ":" instead of "," to separate the variables e.g.

L(X:Y^2)

Regards

Jan

                              
I'm always getting "Invalid Equation" with Let and Get
Message #8 Posted by Eddie Shore on 24 Feb 2004, 11:53 p.m.,
in response to message #7 by Jan (CH)

Apparently, the HP17BII+ (the newest one) doesn't have L() and G(). Nor does STO and RCL have any function in the Solver.

Thankfully, I can get around it, even if it means having to solve for an intermediate variable first.

i.e.

SAMPLE: IF(S(T):T^2-Y:C*Y^3+B*Y^2-A)) You ultimately wanting A,B, or C, but have to solve for T first.

Eddie

      
Re: 17bii Let and Get L() and G()
Message #9 Posted by Rick on 24 Feb 2004, 3:00 p.m.,
in response to message #1 by bill platt

Don't bother. The L-G functions don't allow to solve iteratively for the variable, which sort of defeats the purpose of having a solver at all. I found no real reason to use L-G other than to save keystrokes.

Rick


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