Horizontal sundial calculations: Difference between revisions
J: rephrase to highlight use of atan2
(J: avoid principal value issue) |
(J: rephrase to highlight use of atan2) |
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Line 482:
<lang j>require 'trig'
atan2=: {:@*.@j. NB. arc tangent of y divided by x
horiz=: verb define
'lat lng ref'=. y
Line 492 ⟶ 493:
'Diff longitude ' out -diff=. ref - lng
lbl=.'hour ';'sun hour angle ';'dial hour line angle'
r=.((,. (,. (
smoutput lbl ,: ('3.0';'7.3';'7.3') 8!:1 r
)</lang>
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