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| author | Edward M. Reingold <reingold@emr.cs.iit.edu> | 1996-03-30 00:07:35 +0000 |
|---|---|---|
| committer | Edward M. Reingold <reingold@emr.cs.iit.edu> | 1996-03-30 00:07:35 +0000 |
| commit | 357408a4d8b8acfa7fb790634f915a5eb8df1c79 (patch) | |
| tree | 502a5d70cdfe022176ed1cd3f2acfb621bad1741 /lisp/calendar | |
| parent | 7d4b5109a07faf98cfc3971ca71edb24176fc880 (diff) | |
| download | emacs-357408a4d8b8acfa7fb790634f915a5eb8df1c79.tar.gz | |
Fixed solar-arcsin/arcos stuff.
Diffstat (limited to 'lisp/calendar')
| -rw-r--r-- | lisp/calendar/solar.el | 32 |
1 files changed, 17 insertions, 15 deletions
diff --git a/lisp/calendar/solar.el b/lisp/calendar/solar.el index 7286c241e4c..3a573620ab2 100644 --- a/lisp/calendar/solar.el +++ b/lisp/calendar/solar.el @@ -232,19 +232,20 @@ Returns nil if nothing was entered." (defun solar-atn2 (x y) "Arctan of point X, Y." - (if (= y 0) - (if (> x 0) 90 270) - (solar-arctan (/ x y) y))) + (if (= x 0) + (if (> y 0) 90 270) + (solar-arctan (/ y x) x))) (defun solar-arccos (x) - "Arcos of X." - (let ((y (sqrt (- 1 (* x x))))) - (solar-arctan (/ y x) (solar-xy-to-quadrant x y)))) + "Arcos of X." + (let ((y (sqrt (- 1 (* x x))))) + (solar-atn2 x y))) (defun solar-arcsin (y) - "Arcsin of Y." - (let ((x (sqrt (- 1 (* y y))))) - (solar-arctan (/ y x) (solar-xy-to-quadrant x y)))) + "Arcsin of Y." + (let ((x (sqrt (- 1 (* y y))))) + (solar-atn2 x y) + )) (defsubst solar-degrees-to-hours (degrees) "Convert DEGREES to hours." @@ -290,8 +291,9 @@ degrees to find out if polar regions have 24 hours of sun or only night." (setq day-length 24) (setq day-length 0)) (setq day-length (- set-time rise-time))) - (list (+ rise-time (/ calendar-time-zone 60.0)) - (+ set-time (/ calendar-time-zone 60.0)) day-length))) + (list (if rise-time (+ rise-time (/ calendar-time-zone 60.0)) nil) + (if set-time (+ set-time (/ calendar-time-zone 60.0)) nil) + day-length))) (defun solar-moment (direction latitude longitude time) "Sunrise/sunset at location. @@ -336,7 +338,7 @@ Uses binary search." (if (< hut -0.61) (setq utmin utmoment)) (if (> hut -0.61) (setq utmax utmoment)) ) - (setq possible 0)) the sun never rises + (setq possible 0)) ; the sun never rises (setq possible 0)) ; the sun never sets (if (equal possible 0) nil utmoment))) @@ -512,11 +514,11 @@ The azimuth is given in degrees as well as the height (between -180 and 180)." (ah (- (* st 15) (* 15 (car ec)) (* -1 (calendar-longitude)))) ; hour angle (in degrees) (de (car (cdr ec))) - (azimuth (solar-atn2 (solar-sin-degrees ah) - (- (* (solar-cosine-degrees ah) + (azimuth (solar-atn2 (- (* (solar-cosine-degrees ah) (solar-sin-degrees latitude)) (* (solar-tangent-degrees de) - (solar-cosine-degrees latitude))))) + (solar-cosine-degrees latitude))) + (solar-sin-degrees ah))) (height (solar-arcsin (+ (* (solar-sin-degrees latitude) (solar-sin-degrees de)) (* (solar-cosine-degrees latitude) |