[HP 35s] Hosoda trig program giving incorrect answers to certain angles

[Marcio]

(08-05-2015 02:49 PM)toml_12953 Wrote:  Could it be related to the fact that near 90° the 35s trig functions have very limited accuracy? (about four digits only)

Tom L

Well, the 35s does have troubles getting all digits correct when the angles are very small (1E-7°) or near 90°, as in 89.9999° (four decimals, not three), but the Hosoda code, a 3rd party program, is supposed to get digits right. I myself have been working with it a lot lately and yesterday, after clearing everything, I noticed this weird behaviour. I suspect it has to do with some registers not being real numbers, and they got erased, I know, it seems crazy but it is all I can remember from yesterday. To make matters worse, while \(e^x\) is stable across the entire domain on the 35s, \(e^{ix}\) shows the same instability as observed on the trig functions calculated by the 35s on those very same angles.