## Makefile -- https://www.jidanni.org/astro/rise_set/mountain/zaokeng/programs/
## Copyright       : https://www.gnu.org/licenses/gpl.html
## Author          : https://www.jidanni.org/
## Created On      : Sat Apr 10 03:55:18 2021
## Last Modified By: Dan Jacobson
## Last Modified On: Tue Apr 13 23:48:49 2021
## Update Count    : 98
export lon=120.866903
export lat= 24.167316
export ASL = 508
tolerance = 1 #Degrees, to the left and right of sun...
Z=$(lat) $(lon)
Y=func='$@(p)'
D=24.185950 120.958117
PP=\
next unless length;\
if ( $$F[-1] < 0 ) { $$first_line = $$_; }\
else {\
    $$sideways = $$F[2] - $(azimuth);\
    if ( abs $$sideways <= $(tolerance) ) { printf "%s\n%s [%.1f]\n\n", $$first_line, $$_, $$sideways; }\
}
dongmao:p; $Y ./$? | perl -anlwe '$(PP)' | fgrep ]
geod:; echo $Z $D | $@ +ellps=WGS84 -I -p -f %.2f #which gives
azimuth = 77.43
elevation:#P.S.: At 10 km curvature of earth is maybe just 10m so no big deal.
	perl -MMath::Trig -wle 'print rad2deg atan ((1692-$(ASL))/9495);' #which give
export elevation = 7.1
skew_for_nuclear_photo:; perl -we 'printf "[%.1f]\n", 69.0 - $(azimuth);'
nuclear_photo:; $Y ./p