HP35s Revisited Trig Quandary Bug # 2

[MarkHaysHarris777]

(02-17-2015 07:52 PM)Thomas Klemm Wrote:  

(02-16-2015 11:53 PM)MarkHaysHarris777 Wrote:  Conclusion: Bug # 2 is not a bug... its a petty annoyance.

You may try this simple program with 0, 1, 2, 3, ... as input. Just make sure to use DEG mode.

Code:

0001 10^x
0002 ENTER
0003 1/x
0004 SIN
0005 ×
0006 RTN

This is the result that the HP-35s produces (using ALL mode):

0: 1.74524064373E^-2
1: 1.7453283659E^-2
2: 1.74532924306E^-2
3: 1.74532925091E^-2
4: 0.0174532925
5: 0.017453292
6: 0.01745329
7: 0.0174532
8: 1.74532925199E^-2
9: 1.74532925199E^-2

hi Thomas, you're making my point for me splendidly... 'nobody' (at least not engineers, nor scientists) runs their calculator in 'all' mode. Perhaps educators, some mathematicians, or the curious, but usually we set the machine to some realistic scope in scientific or engineering format so that the results make sense within bounds and according to the laws of significant figures... I hate being pedantic, but hey, what ever it takes; right?

So, using your program on my HP35s (both units) these are the results with FIX 6 (I normally run my units in FIX 4, because it makes the most sense) :

1: 0.017453
2: 0.017453
3: 0.017453
4: 0.017453
5: 0.017453
6: 0.017453
7: 0.017453
8: 0.017453
9: 0.017453

Your example is a fine excursion down the bunny trail of 'see how messy I can make this petty annoyance look'... when really, there is no problem within the realm of reasonableness and fair representation. Round-trips on an extreme end are also not representative of what most folks (engineers and scientists) are going to run into in everyday work.

Some people are irked by the fact that many real numbers cannot be held in computer memory accurately. The memory of the computer is a 'model' of what's going on in Platonic space; Aristotle is just going to have to live with it-! We do the best we can, with what we have; and my point is that the HP35s is doing not a bad job of it... maybe not up the the 42s or 15C expectation, but reasonably well none-the-less.

Cheers,
marcus