b612
9ee2163cc7
- 新增月掩恒星和行星：支持搜索、掩甚点、全球掩带及固定地点轨迹计算 - 支持恒星星表坐标转换、有限盘面行星接触事件和月掩 SVG 输出 - 新增日月食及月掩全球投影图、时间标记和 GeoJSON 地理数据接口 - 扩展日食中心线、南北界及偏食足迹采样，支持极区投影 - 修正站心时角、月出月落、月球视半径、折射和恒星自行计算 - 优化内外行星事件搜索、边界选择、极端输入处理和计算稳定性
97 lines
2.3 KiB
Go
97 lines
2.3 KiB
Go
package basic
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import "math"
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// GetShiErCi 十二次 / twelve divisions of the ecliptic in traditional Chinese astronomy.
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func GetShiErCi(jd float64) string { //十二次
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tlo := HSunApparentLo(jd)
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if tlo >= 255 && tlo < 285 {
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return "星纪"
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} else if tlo >= 285 && tlo < 315 {
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return "玄枵"
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} else if tlo >= 315 && tlo < 345 {
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return "娵訾"
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} else if tlo >= 345 || tlo < 15 {
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return "降娄"
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} else if tlo >= 15 && tlo < 45 {
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return "大梁"
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} else if tlo >= 45 && tlo < 75 {
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return "实沈"
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} else if tlo >= 75 && tlo < 105 {
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return "鹑首"
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} else if tlo >= 105 && tlo < 135 {
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return "鹑火"
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} else if tlo >= 135 && tlo < 165 {
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return "鹑尾"
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} else if tlo >= 165 && tlo < 195 {
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return "寿星"
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} else if tlo >= 195 && tlo < 225 {
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return "大火"
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} else if tlo >= 225 && tlo < 255 {
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return "析木"
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}
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return ""
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}
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// GetWuHouTime 七十二候时刻 / time of a pentad marker in traditional Chinese calendrics.
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func GetWuHouTime(Year, Angle int) float64 {
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tmp := Angle
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var Day int
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var tp float64
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Angle = int(Angle/15) * 15
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if Angle%2 == 0 {
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Day = 18
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} else {
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Day = 3
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}
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if Angle%10 != 0 {
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tp = float64(Angle+15) / 30.0
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} else {
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tp = float64(Angle) / 30.0
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}
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Month := int(3 + tp)
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if Month > 12 {
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Month -= 12
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}
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JD1 := JDECalc(Year, Month, float64(Day))
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JD1 += float64(tmp - Angle)
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Angle = tmp
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if Angle <= 5 {
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Angle = 360 + Angle
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}
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converged := false
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for i := 0; i < eventNewtonMaxIterations; i++ {
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JD0 := JD1
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stDegree := JQLospec(JD0, float64(Angle)) - float64(Angle)
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stDegreep := (JQLospec(JD0+0.000005, float64(Angle)) - JQLospec(JD0-0.000005, float64(Angle))) / 0.00001
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nextJD := JD0 - stDegree/stDegreep
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if !isFiniteFloat(nextJD) {
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return math.NaN()
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}
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JD1 = nextJD
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if math.Abs(nextJD-JD0) <= 0.00001 {
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converged = true
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break
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}
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}
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if !converged {
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return math.NaN()
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}
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return TD2UT(JD1, false)
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}
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// GetGanZhi 年干支 / ganzhi for a year number.
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func GetGanZhi(year int) string {
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tiangan := []string{"庚", "辛", "壬", "癸", "甲", "乙", "丙", "丁", "戊", "己"}
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dizhi := []string{"申", "酉", "戌", "亥", "子", "丑", "寅", "卯", "辰", "巳", "午", "未"}
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t := year - (year / 10 * 10)
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if t < 0 {
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t += 10
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}
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d := year % 12
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if d < 0 {
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d += 12
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}
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return tiangan[t] + dizhi[d]
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}
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