Sixth Order Linear Equation Solver for the hp 33s - Printable Version +- HP Forums ( https://archived.hpcalc.org/museumforum)+-- Forum: HP Museum Forums ( https://archived.hpcalc.org/museumforum/forum-1.html)+--- Forum: Old HP Forum Archives ( https://archived.hpcalc.org/museumforum/forum-2.html)+--- Thread: Sixth Order Linear Equation Solver for the hp 33s ( /thread-99843.html) |

Sixth Order Linear Equation Solver for the hp 33s - Palmer O. Hanson, Jr. - 09-16-2006
As part of a continuing effort to explore the capabilities of the hp 33s I have translated a sixth order linear equation solver for use on that machine. The documentation is much too long for a Forum topic so it has been entered as Article 676.
I believe that by judicious use of the statistics registers I should be able to fit a seventh order solver on the hp 33s but I haven't been able to push it through yet. I'm still working on it.
Re: Sixth Order Linear Equation Solver for the hp 33s - ECL - 09-17-2006
I'm very enthusiastic to give the program a try! A lack of super-3x3 matrix support is the primary reason that my 33s has been in probation for the last 8 months.
Thanks, Expansion to seventh order - Palmer O. Hanson, Jr. - 09-17-2006
It turns out that it was not very difficult to expand the program to solve a seventh order set of linear equations. The changes required are: 1. Insert a CLSum command immediately after the CLVARS near the beginning of the program. 2. Add the following subroutine at the end of the program:
T0001 LBL T 3. Replace the STO i command with a XEQ T command at the following program locations:
B0003 The operating instructions are not changed.
For the test problem with a seventh order sub-Hilbert as the matrix A and all ones as the vector B the results are Exact hp 33s Relative Errorfor a mean relative error of 0.878E-03. For the same problem the HP-41 MathPac yields a mean relative error of 0.837E-02 and the ML-02 program for the TI-59 yields a mean relative error of 1.033E-04. In a subsequent submission I will provide comparisons with other machines and with other problems. Re: Sixth Order Linear Equation Solver for the hp 33s - Gerson W. Barbosa - 09-17-2006
That's really impressive! Now, a fourth or even a third order Complex Linear Equation Solver would be great, but that would be asking too much, I recognize :-) One of the things that impressed me in my first decent programmable calculator, a TI-59 back in 1982, was its matrix abilities (ML-02 and ML-03). It would invert a 9x9 matrix in about 12 minutes! Thanks for your continued efforts in writing and porting excellent software to the HP-33S. Best regards, Gerson W. Barbosa.
Mea Culpa - Palmer O. Hanson, Jr. - 09-18-2006
The original sixth order program in Article 676 would run equally well in either RPN mode or ALG mode. My modification above of the program to provide a seventh order capability will run properly in ALG mode but will not run properly for all N when in RPN mode. To run properly in RPN mode the T subroutine must be modified by removing the x<>Y commsnd at T0003. The T subroutine for use in RPN mode then becomes:
T0001 LBL T |