Variable: solar-error

solar-error is a customizable variable defined in solar.el.gz.

Value

0.5

Documentation

Tolerance (in minutes) for sunrise/sunset calculations.

A larger value makes the calculations for sunrise/sunset faster, but less accurate. The default is half a minute (30 seconds), so that sunrise/sunset times will be correct to the minute.

It is useless to set the value smaller than 4*delta, where delta is the accuracy in the longitude of the sun (given by the function solar-ecliptic-coordinates) in degrees since (delta/360) x (86400/60) = 4 x delta. At present, delta = 0.01 degrees, so the value of the variable solar-error should be at least 0.04 minutes (about 2.5 seconds).

Source Code

;; Defined in /usr/src/emacs/lisp/calendar/solar.el.gz
(defcustom solar-error 0.5
  "Tolerance (in minutes) for sunrise/sunset calculations.

A larger value makes the calculations for sunrise/sunset faster, but less
accurate.  The default is half a minute (30 seconds), so that sunrise/sunset
times will be correct to the minute.

It is useless to set the value smaller than 4*delta, where delta is the
accuracy in the longitude of the sun (given by the function
`solar-ecliptic-coordinates') in degrees since (delta/360) x (86400/60) = 4 x
delta.  At present, delta = 0.01 degrees, so the value of the variable
`solar-error' should be at least 0.04 minutes (about 2.5 seconds)."
  :type 'number
  :group 'calendar)