GOLDEN-SECTION Method For HP-67/97

[plore90]

Hello everyone,
I'm here to present you my latest program written for HP-67/97 calculators but also adaptable to HP-41C: "Absolute Minimum and Maximum for a function F(X) defined and continuous in an interval [Xlow,Xupper] with the GOLDEN-SECTION Search method".
This method does not use derivatives, but has linear convergence and is therefore slower than Newton's method. In the attached zip file you will find the following files,
1) Hp6797_MINMAXFX.67 which contains the program to be read by the HP-67 emulator by LIMPIDFOX.
2) Hp6797_MINMAXFX.PDF which contains the program listing
3) Hp6797_MINMAXFX.TXT which contains the instructions.
Plus one in English, which explain the GOLDEN-SECTION method and show some examples.
I hope as usual that this program can be useful to some of you.
Thanks for the attention.
Plore90
Update!!!
I updated the LBLA and LBLB so as not to re-enter the ends of the interval between a D calculation and an E calculation.

https://en.wikipedia.org/wiki/Golden_ratio
https://en.wikipedia.org/wiki/Golden-section_search