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+--- Thread: Hp50g MES (/thread-15326.html)
Hp50g MES - Tugdual - 07-09-2020 04:03 PM
Does anybody know what algorithm is used in the Hp50g Multiple Equation Solver?
RE: Hp50g MES - Joe Horn - 07-10-2020 03:27 AM
The HP Solve Equation Library Application Card Owner's Manual says on page 169:
"When you solve problems using the Multiple-Equation Solver, the application uses the same numeric root finder that's used by the HP Solve application, which is built into the HP 48."
I assume that the same is true for the HP 50g.
RE: Hp50g MES - Tugdual - 07-10-2020 10:44 AM
(07-10-2020 03:27 AM)Joe Horn Wrote: The HP Solve Equation Library Application Card Owner's Manual says on page 169:
"When you solve problems using the Multiple-Equation Solver, the application uses the same numeric root finder that's used by the HP Solve application, which is built into the HP 48."
I assume that the same is true for the HP 50g.
Thanks Joe. Would that then be a non linear equation solver? Like Levenberg-Marquardt method?
RE: Hp50g MES - Joe Horn - 07-10-2020 12:13 PM
(07-10-2020 10:44 AM)Tugdual Wrote: Would that then be a non linear equation solver? Like Levenberg-Marquardt method?
Anybody know? If it's the same as the solver that HP first introduced in the HP-34C, then it's a "modified secant iteration method" as explained here by Dr Kahan himself in 1979: https://people.eecs.berkeley.edu/~wkahan/Math128/SOLVEkey.pdf
RE: Hp50g MES - JurgenRo - 07-10-2020 06:35 PM
(07-10-2020 12:13 PM)Joe Horn Wrote:(07-10-2020 10:44 AM)Tugdual Wrote: Would that then be a non linear equation solver? Like Levenberg-Marquardt method?
Anybody know? If it's the same as the solver that HP first introduced in the HP-34C, then it's a "modified secant iteration method" as explained here by Dr Kahan himself in 1979: https://people.eecs.berkeley.edu/~wkahan/Math128/SOLVEkey.pdf
Thanks for the reading, Joe!
RE: Hp50g MES - ndzied1 - 07-10-2020 09:07 PM
Not sure if this is what is used in the 50g but here is an HP patent for a multiple equation solver. It seems to be more about the multiple equation part than the solving of each equation.
https://patents.google.com/patent/US5175700
Method and apparatus for solving multiple equations
It also references this patent:
https://patents.google.com/patent/US4845652A/en
Generic equation solver interface for solving mathematical equations
Very much wish the Prime will eventually incorporate this type of multiple equation solving.
RE: Hp50g MES - Thomas Okken - 07-10-2020 09:41 PM
It sounds like this older topic might be relevant... not my area of expertise but hoping it may be useful: Multiple equation solver for the HP-28C (program)
RE: Hp50g MES - Tugdual - 07-13-2020 04:18 PM
Thanks all for the replies.
So to summarize it would be a sort of combination of an algo to try to solve obvious solutions, when only one variable remains and/or a secant method applied to multiple variables, hence something resembling https://en.wikipedia.org/wiki/Broyden%27s_method to expand on mutliple variables.