HP 15C and INT(1/√(1-x),0,1)

[Dieter]

(01-11-2018 06:35 PM)Mike (Stgt) Wrote:  Do you have the MoHP CD? Did you find the PPC ROM Users's Manual there? Did you read what's written about routine IG - Integrate?
...
SIZE 030
"XF1" ASTO 10
FIX 2
0 ENTER 1
XEQ IG

Result: 2.00

Any questions? (Timing you may test on your own machine.)

I neither own a physical Advantage ROM nor the PPC ROM, but I have V41 here, which is set to a speed that very closely matches that of a real '41.

- With FIX 2 set, the Advantage Pac's INTEG routine returns 1,99 after 1:34 minutes.
- The PPC ROM's IG routine (which shows successive approcimations) arrives at this point after about 3 minutes.
- The PPC ROM stops after two successive approximations with the same result, rounded to display precision. This requires 9:20 minutes with a final result of 2,00.

BTW both ROMs have different integration algorithms. The PPC ROM's IG program is a classic Romberg method while the Advantage ROM's INTEG routine seems to implement the same (or at least a similar) method as the 34C or 15C. While no details have been officially published it was said that this is "a Romberg method" with a modified way of sampling the function values.

Dieter