On Monday, November 4, 2013 7:26:07 PM UTC-5, Rich Ulrich wrote: >On Mon, 4 Nov 2013 10:03:47 -0800 (PST), paul wrote: > How are curves obtained? Industries probably observed the > picture before they described it mathematically. Ball-bearings. > Light-bulbs. Lots of experience. Set in your numbers and > simulate it.
I have to cite a reference for completeness because I allude to it in a report.