HP71B Integral Questions

[J-F Garnier]

(02-07-2020 01:19 PM)Wes Loewer Wrote:  

(02-07-2020 08:23 AM)J-F Garnier Wrote:  the sampled points corresponds to the u values of 0, +/-0.5, +/-0.25, +/-0.75.

Yes, those are the points that you would expect using midpoints. These are the same points used on the 50g.

n=1: the rectangle goes from -1 to 1 with a midpoint at 0
n=2: rectangles go from -1 to 0 and 0 to 1 with midpoints at -0.5, 0.5
n=4: rectangles go from -1 to -0.5, -0.5 to 0, 0 to 0.5, and 0.5 to 1 with midpoints at -0.75, -0.25, 0.25, 0.75

I understand that the 7 values are a single (combined) set of samples, with 8 regions from -1 to -0.75, -0.75 to -0.5 etc.
For these 8 regions, midpoints would be -0.875, -0.625, etc.

The key point may be that from from one iteration to another, the HP71 doesn't compute a new integral forgetting the previous samples, but combines them with new samples (according to the HP articles/manuals).

J-F