Re: HP17bII+ recursive programing Message #2 Posted by sbirdasn on 9 May 2005, 5:28 p.m., in response to message #1 by christopher dean
I don't own one, and the site doesn't have specifics on the 17BII, but I'll take a stab at it
Does the 17BII have RPL? If not, then any subroutine capabilities are in all likelihood only about 78 levels deep (assuming it's Saturn CPU based). Most recursion methods require fairly deep subroutine nesting to be of much value, so not much use on limited machines with shallow call/return stacks/registers.
Also, the limited information on other algebraic calculators that this site contains doesn't imply much in the way of programmability. Can you even access one formula entered from another one? If so, then that by definition is like a subroutine call, so any limits on subroutine depth would be measured in the number of formulas that can reference other entered formulas. Is there any conditionals allowed in a formula? If not, then recursion is pointless, as you need some means to control the recursion depth in the first place.
As for intermediate values, are you thinking of the x,y,x*y,x^2... summation registers? If that is the case, then there should be a recall function to get at the present summation total for each summation statistic kept. Note that each summation quantity is a running total, so there isn't "history" on each data point entered. This makes sense, as there is no intrinsic limit on the number of data points in a statistical analysis excepting rounding/overflow errors in the summations themselves. Normalizing the data reduces these effects and allows for much larger data sets without losing accuracy.
Any other information behind a keyboard function or statistical operation besides that returned by the function would simply not be available. Can't imagine how that would be possible, unless you can perform some feat of synthetic programming, and even then, probably not anything useful would be left in various working registers or scratch pad memory.
Hope that helps answer your questions.
sbirdasn.
Edited: 9 May 2005, 11:08 p.m.
