re: going back to the roots



i am reading Valentin's article just out in V26N5, "going back to the roots".

therein is a complex root solver for the 35s. i was keen to try this out, but i can't get it to work properly on my calculator. i do think that algorithms for complex numbers have been somewhat ignored and this helps to redress that and demonstrate the 35s' comples number features.

since my calculator is new, its likely that i've made some blunder. the second line of code: regx*(1i0->z)->x. what is "regx"? is this just x*(1i0->z)->x or something i've missed?

example 1: works!
example 2: all inputs give 2
example 3: works
example 4: all give 1.3688....
example 5: all give 2.32883 i 0.29914

so basically, im seeing convergence to a favorite root and that is it.

any help? i'll double check again tomorrow for blunders. thanks.

serial# CNA 73400764


REGX is a reference to stack register X. In HP41-speak, it is a RCL X.

To enter it into an equation in the HP 35s, do the following in program mode.

Since this is already an equation in this line of the program, press RDN. Now move over and press ENTER underneath the X in the list of stack registers. This will insert a REGX. Continue entering the rest of the equation.

It looks as if you have the -> symbol in the equation. I'm assuming this is the "triangle" store symbol which would store the value into a regular letter register.

See: hp35s learning module on stack access



Hi, Hugh:

    Thanks for your interest and sorry for the problems you're having entering that program line.

    Gene's explanations below are quite correct and you'd do well reading the HP35s learning module he links. Meanwhile, these are the exact keys you should press in PROGRAM mode to enter line A0002:

    (where the ">" key is the Cursor-Right key, of course) and the resulting program line will look like this:

    The article does include Length and Checksum for each and every equation, but due to bugs in both counts, they aren't that useful.

    Hope this solves your problem, check all examples to see that you get the exact same results as featured in my article.

Best regards from V.


hi guys, it works!!

thanks gene for this help and thanks valentin for spelling it out.

my apologies for being a bone head and not reading the manual properly. it's too tempting to hack away with the machine. there is quite a lot more to the 35s than meets the eye with its "secret" menus. easter eggs of the 35s anyone?


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