func ExampleRadius() {
// Example 25.a, p. 165.
T := base.J2000Century(julian.CalendarGregorianToJD(1992, 10, 13))
fmt.Printf("%.5f AU\n", solar.Radius(T))
// Output:
// 0.99766 AU
}
func TestPhaseAngleEcl(t *testing.T) {
j := julian.CalendarGregorianToJD(1992, 4, 12)
λ, β, Δ := moonposition.Position(j)
T := base.J2000Century(j)
λ0 := solar.ApparentLongitude(T)
R := solar.Radius(T) * base.AU
i := moonillum.PhaseAngleEcl(λ, β, Δ, λ0, R)
ref := 69.0756 * math.Pi / 180
if math.Abs((i-ref)/ref) > 1e-4 {
t.Errorf("i = %.4f", i*180/math.Pi)
}
}