George Neuner <gneun...@comcast.net> writes: > On 28 Sep 2010 12:42:40 GMT, Albert van der Horst > <alb...@spenarnc.xs4all.nl> wrote: >>I would say the dimensional checking is underrated. It must be >>complemented with a hard and fast rule about only using standard >>(SI) units internally. >> >>Oil output internal : m^3/sec >>Oil output printed: kbarrels/day > > "barrel" is not an SI unit.
He didn't say it was. Internal calculations are done in SI units (in this case, m^3/sec); on output, the internal units can be converted to whatever is convenient. > And when speaking about oil there isn't > even a simple conversion. > > 42 US gallons ? 34.9723 imp gal ? 158.9873 L > > [In case those marks don't render, they are meant to be the > double-tilda sign meaning "approximately equal".] There are multiple different kinds of "barrels", but "barrels of oil" are (consistently, as far as I know) defined as 42 US liquid gallons. A US liquid gallon is, by definition, 231 cubic inches; an inch is, by definition, 0.0254 meter. So a barrel of oil is *exactly* 0.158987294928 m^3, and 1 m^3/sec is exactly 13.7365022817792 kbarrels/day. (Please feel free to check my math.) That's admittedly a lot of digits, but there's no need for approximations (unless they're imposed by the numeric representation you're using). -- Keith Thompson (The_Other_Keith) ks...@mib.org <http://www.ghoti.net/~kst> Nokia "We must do something. This is something. Therefore, we must do this." -- Antony Jay and Jonathan Lynn, "Yes Minister" -- http://mail.python.org/mailman/listinfo/python-list
