On Monday, August 18, 2014 7:21:53 PM UTC+5:30, Joel Goldstick wrote: > On Mon, Aug 18, 2014 at 9:12 AM, luofeiyu wrote: > > I found that it is a concept LMT local mean time can express my meaning.
> Local Mean Time is time based on the actually astronomical position of > the sun. It is defined as 12 noon when the sun is at its high point, > directly south in the sky. This is the time you get when you read a > sundial! > So each town or village set their clocks differently. That all > changed with the railroad industry. Once trains began traveling, time > zones were invented so that everyone knew exactly what time it was in > order to keep trains from meeting on the same tracks and colliding. > Trains need time schedules. Time zones make this possible. Add to that the fact that any two places even say a kilometer apart, will have different LMT. Naturally if one chooses a least count, say 1 sec, then that distance will be larger. 40075 km equatorial circumference 86400 secs in a day (60×60×24) 40075/86400 = 2.1 ie LMT changes by 1 sec for every 2.1 km E-W along the equator And even here the distance would shrink going towards the poles. -- https://mail.python.org/mailman/listinfo/python-list
