# HP Forums

Full Version: Decimals to improper fractions program?
You're currently viewing a stripped down version of our content. View the full version with proper formatting.
Pages: 1 2
Found this on HP Newsletter issue #25

Decimal to Fraction for the HP-35S by Joseph K. Horn

On Page 35

Gamo
(08-13-2018 03:03 AM)Albert Chan Wrote: [ -> ]
(06-09-2018 02:54 PM)Csaba Tizedes Wrote: [ -> ]In engineering practice more important the relative error. In this case the results are:
Code:
```+/- 1.000% error:  19/6,  +/- 0.100% error:  22/7,  +/- 0.010% error: 289/92,  +/- 0.001% error: 355/113```

Above table is mistaken, 355/113 is 100 times more accurate.
355/113 vs Pi, relative error = 85e-9 = 0.0000085%

I think the idea of the table is to give a fraction that – at least – matches a certain accuracy level. So if you need an accuracy of 0,001% or better, 355/113 is the first fraction to meet that target.

(08-13-2018 03:03 AM)Albert Chan Wrote: [ -> ]I agree that relative error is more useful than digits matched.
All estimates below had 5% relative error, but digits matched are all over the place.

That's exactly why I prefer stating the number of matching digits.
But I am not an engineer. ;-)

Dieter
Pages: 1 2
Reference URL's
• HP Forums: https://www.hpmuseum.org/forum/index.php
• :