Will Anderson
24 lines
915 B
EmacsLisp
24 lines
915 B
EmacsLisp
// cycle-300yr.el — CycleCalendar with a 100-year period proves the math
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// holds at long periods. (300 years exceeds int64 nanos: 2^63 ns ≈ 292 yr;
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// 100 yr is the largest round period that fits while leaving headroom for
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// instants on either side.) One earth year apart yields phase_diff ~ 0.01.
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fn run_test() -> String {
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// 100 Julian years = 100 * 31557600 = 3155760000 seconds.
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let period: Duration = duration_seconds(3155760000)
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let cal: Calendar = cycle_calendar(period)
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let base: Instant = unix_seconds(0)
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let later: Instant = unix_seconds(31557600)
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let ct1: CalendarTime = in_calendar(base, cal)
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let ct2: CalendarTime = in_calendar(later, cal)
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let p1: Float = cal_cycle_phase(ct1)
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let p2: Float = cal_cycle_phase(ct2)
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let diff: Float = p2 - p1
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// 1 year / 100 years = 0.01
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return format_float(diff, 2)
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}
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fn main() -> Void {
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println(run_test())
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}
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