WP-34S Integration speed - Printable Version +- HP Forums (https://www.hpmuseum.org/forum) +-- Forum: Not HP Calculators (/forum-7.html) +--- Forum: Not quite HP Calculators - but related (/forum-8.html) +--- Thread: WP-34S Integration speed (/thread-731.html) WP-34S Integration speed - lrdheat - 02-21-2014 03:08 AM Is there a way to balance accuracy with speed of integration on the 34S as with HP's that can integrate? The HP's give the user the ability to require, say, 4 significant digits of accuracy vs. the full 12 digits in order to arrive at a result in a significantly shorter amount of time. Can this be accomplished on the wonderful 34S? RE: WP-34S Integration speed - Marcus von Cube - 02-22-2014 11:44 AM The integration routine is modeled after the IG routine from the HP 41 PPC ROM. It uses the display accuracy to determine the number of iterations by means of the x≈ Y comparison command. You can improve the integration speed by setting a different display mode such as FIX 4 or SCI 4. RE: WP-34S Integration speed - Paul Dale - 02-22-2014 12:35 PM However, an integral that is approximately zero will hit a snag and will continue iterating long after it should. Nobody like the Gauss-Kronrod quadrature I initially implemented which was fast and good for smooth functions but in no way adaptive. - Pauli RE: WP-34S Integration speed - Dieter - 02-23-2014 02:02 PM (02-22-2014 12:35 PM)Paul Dale Wrote:  However, an integral that is approximately zero will hit a snag and will continue iterating long after it should. Pauli, I remember we had a discussion on this very topic some time ago, and I suggested a possible fix: compare the current value of $$\int f(x)$$ with an approximation of $$\int |f(x)|$$. It worked well with the examples we discussed then. Details can be found here, cf. message 6 ff. This change was supposed to get implemented in v. 3460 resp. 3462. So I thought this issue had been resolved. Dieter RE: WP-34S Integration speed - Paul Dale - 02-23-2014 09:42 PM Sorry, Dieter is correct. We implemented a fix for the integral approaching zero. I'd just forgotten about it. - Pauli RE: WP-34S Integration speed - Dave Hicks - 02-27-2014 12:14 AM This thread was moved from the General forum by request. RE: WP-34S Integration speed - walter b - 02-27-2014 06:43 AM χαιρε, Δρακων. Now it's where ο δημος will look for it. d:-) RE: WP-34S Integration speed - Dieter - 02-27-2014 02:28 PM (02-23-2014 09:42 PM)Paul Dale Wrote:  We implemented a fix for the integral approaching zero. I see the fix got implemented, but one final improvement I posted back then still is missing (cf. last message in the mentioned thread). It's one single line that should be added: Code:         ...         FC?C f_final        /* final iteration done? */         x[approx]? Y        /* or convergence? */              JMP int_done         RCL/ r_SkAbs         RCL/ r_deltau         RCL/ r_ba4        <==  add this line         ABS         ... Maybe it can be added with the next update. Dieter RE: WP-34S Integration speed - Paul Dale - 02-27-2014 09:28 PM Dieter, I must have missed that final improvement. Added now but not built. - Pauli RE: WP-34S Integration speed - Marcus von Cube - 03-02-2014 01:15 PM (02-27-2014 09:28 PM)Paul Dale Wrote:  Dieter, I must have missed that final improvement. Added now but not built. My Job! Build 3530 is Committed to SVN...