package com.sven.calendar.utils;
import android.content.Context;
import com.sven.calendar.R;
import java.util.Calendar;
/**
* @author lxslove
* @mail moodlxs@163.com
*
* @see http://www.doc88.com/p-211656359926.html 原理，http://www.fjptsz.com/xxjs/xjw/rj/115.htm web版
*/
public class SolarTerm {
// ========角度变换===============
private static final double rad = 180 * 3600 / Math.PI; // 每弧度的角秒数
private static final double RAD = 180 / Math.PI; // 每弧度的角度数
// ================日历计算===============
private static final double J2000 = 2451545; // 2000年前儒略日数(2000-1-1 12:00:00格林威治平时)
// =========黄赤交角及黄赤坐标变换===========
private static final double hcjjB[] = { 84381.448, -46.8150, -0.00059,
0.001813 };// 黄赤交角系数表
private static final double preceB[] = { 0, 50287.92262, 111.24406,
0.07699, -0.23479, -0.00178, 0.00018, 0.00001 };// Date黄道上的岁差p
private double Y = 2000;
private double M = 1;
private double D = 1;
private double h = 12;
private double m = 0;
private double s = 0;
private static final double[] dts = {
// 世界时与原子时之差计算表
-4000, 108371.7, -13036.80, 392.000, 0.0000, -500, 17201.0,
-627.82, 16.170, -0.3413, -150, 12200.6, -346.41, 5.403, -0.1593,
150, 9113.8, -328.13, -1.647, 0.0377, 500, 5707.5, -391.41, 0.915,
0.3145, 900, 2203.4, -283.45, 13.034, -0.1778, 1300, 490.1, -57.35,
2.085, -0.0072, 1600, 120.0, -9.81, -1.532, 0.1403, 1700, 10.2,
-0.91, 0.510, -0.0370, 1800, 13.4, -0.72, 0.202, -0.0193, 1830,
7.8, -1.81, 0.416, -0.0247, 1860, 8.3, -0.13, -0.406, 0.0292, 1880,
-5.4, 0.32, -0.183, 0.0173, 1900, -2.3, 2.06, 0.169, -0.0135, 1920,
21.2, 1.69, -0.304, 0.0167, 1940, 24.2, 1.22, -0.064, 0.0031, 1960,
33.2, 0.51, 0.231, -0.0109, 1980, 51.0, 1.29, -0.026, 0.0032, 2000,
64.7, -1.66, 5.224, -0.2905, 2150, 279.4, 732.95, 429.579, 0.0158,
6000 };
// 取整数部分
public static double int2(double v) {
v = Math.floor(v);
if (v < 0)
return v + 1;
return v;
}
// 对超过0-2PI的角度转为0-2PI
public static double rad2mrad(double v) {
v = v % (2 * Math.PI);
if (v < 0)
return v + 2 * Math.PI;
return v;
}
// 计算世界时与原子时之差,传入年
public double deltatT(double y) {
int i = 0;
for (i = 0; i < 100; i += 5)
if (y < dts[i + 5] || i == 95)
break;
double t1 = (y - dts[i]) / (dts[i + 5] - dts[i]) * 10;
double t2 = t1 * t1;
double t3 = t2 * t1;
return dts[i + 1] + dts[i + 2] * t1 + dts[i + 3] * t2 + dts[i + 4] * t3;
}
// 传入儒略日(J2000起算),计算UTC与原子时的差(单位:日)
public double deltatT2(double jd) {
return this.deltatT(jd / 365.2425 + 2000) / 86400.0;
}
// 公历转儒略日,UTC=1表示原日期是UTC
public double toJD(boolean UTC) {
double y = this.Y; // 取出年月
double m = this.M;
double n = 0;
if (m <= 2) {
m += 12;
y--;
}
if (this.Y * 372 + this.M * 31 + this.D >= 588829) {
// 判断是否为格里高利历日1582*372+10*31+15
n = int2(y / 100);
n = 2 - n + int2(n / 4);// 加百年闰
}
n += int2(365.2500001 * (y + 4716)); // 加上年引起的偏移日数
n += int2(30.6 * (m + 1)) + this.D; // 加上月引起的偏移日数及日偏移数
n += ((this.s / 60 + this.m) / 60 + this.h) / 24 - 1524.5;
if (UTC)
return n + this.deltatT2(n - J2000);
return n;
}
// 儒略日数转公历,UTC=1表示目标公历是UTC
public void setFromJD(double jd, boolean UTC) {
if (UTC)
jd -= this.deltatT2(jd - J2000);
jd += 0.5;
// 取得日数的整数部份A及小数部分F
double A = int2(jd);
double F = jd - A;
double D;
if (A > 2299161) {
D = int2((A - 1867216.25) / 36524.25);
A += 1 + D - int2(D / 4);
}
A += 1524; // 向前移4年零2个月
this.Y = int2((A - 122.1) / 365.25);// 年
D = A - int2(365.25 * this.Y); // 去除整年日数后余下日数
this.M = int2(D / 30.6001); // 月数
this.D = D - int2(this.M * 30.6001);// 去除整月日数后余下日数
this.Y -= 4716;
this.M--;
if (this.M > 12)
this.M -= 12;
if (this.M <= 2)
this.Y++;
// 日的小数转为时分秒
F *= 24;
this.h = int2(F);
F -= this.h;
F *= 60;
this.m = int2(F);
F -= this.m;
F *= 60;
this.s = F;
}
// 设置时间,参数例:"20000101 120000"或"20000101"
public void setFromStr(String s) {
this.Y = Double.parseDouble(s.substring(0, 4));
this.M = Double.parseDouble(s.substring(4, 2));
this.D = Double.parseDouble(s.substring(6, 2));
this.h = Double.parseDouble(s.substring(9, 2));
this.m = Double.parseDouble(s.substring(11, 2));
this.s = Double.parseDouble(s.substring(13, 2)); /* 将5改为了2 */
}
// 日期转为串
public String toStr() {
String Y = " " + (int) this.Y;
String M = "0" + (int) this.M;
String D = "0" + (int) this.D;
double h = this.h, m = this.m, s = Math.floor(this.s + .5);
if (s >= 60) {
s -= 60;
m++;
}
if (m >= 60) {
m -= 60;
h++;
}
String sh = "0" + (int) h, sm = "0" + (int) m, ss = "0" + (int) s;
Y = Y.substring(Y.length() - 5, Y.length());
M = M.substring(M.length() - 2, M.length());
D = D.substring(D.length() - 2, D.length());
sh = sh.substring(sh.length() - 2, sh.length());
sm = sm.substring(sm.length() - 2, sm.length());
ss = ss.substring(ss.length() - 2, ss.length());
return Y + "-" + M + "-" + D + " " + sh + ":" + sm + ":" + ss;
}
// 算出:jd转到当地UTC后,UTC日数的整数部分或小数部分
// 基于J2000力学时jd的起算点是12:00:00时,所以跳日时刻发生在12:00:00,这与日历计算发生矛盾
// 把jd改正为00:00:00起算,这样儒略日的跳日动作就与日期的跳日同步
// 改正方法为jd=jd+0.5-deltatT+shiqu/24
// 把儒略日的起点移动-0.5(即前移12小时)
// 式中shiqu是时区,北京的起算点是-8小时,shiqu取8
public double Dint_dec(double jd, int shiqu, boolean dec) {
double u = jd + 0.5 - this.deltatT2(jd) + shiqu / 24;
if (dec)
return Math.floor(u); // 返回整数部分
else
return u - Math.floor(u); // 返回小数部分
}
// 计算两个日期的相差的天数,输入字串格式日期,如:"20080101"
double d1_d2(String d1, String d2) {
double Y = this.Y, M = this.M, D = this.D, h = this.h, m = this.m, s = this.s; // 备份原来的数据
this.setFromStr(d1.substring(0, 8) + " 120000");
double jd1 = this.toJD(false);
this.setFromStr(d2.substring(0, 8) + " 120000");
double jd2 = this.toJD(false);
this.Y = Y;
this.M = M;
this.D = D;
this.h = h;
this.m = m;
this.s = s; // 还原
if (jd1 > jd2)
return Math.floor(jd1 - jd2 + .0001);
else
return -Math.floor(jd2 - jd1 + .0001);
}
// 返回黄赤交角(常规精度),短期精度很高
public static double hcjj1(double t) {
double t1 = t / 36525;
double t2 = t1 * t1;
double t3 = t2 * t1;
return (hcjjB[0] + hcjjB[1] * t1 + hcjjB[2] * t2 + hcjjB[3] * t3) / rad;
}
// 黄赤转换(黄赤坐标旋转)
public static void HCconv(double[] JW, double E) {
// 黄道赤道坐标变换,赤到黄E取负
double HJ = rad2mrad(JW[0]), HW = JW[1];
double sinE = Math.sin(E), cosE = Math.cos(E);
double sinW = cosE * Math.sin(HW) + sinE * Math.cos(HW) * Math.sin(HJ);
double J = Math.atan2(Math.sin(HJ) * cosE - Math.tan(HW) * sinE,
Math.cos(HJ));
JW[0] = rad2mrad(J);
JW[1] = Math.asin(sinW);
}
// 补岁差
public static void addPrece(double jd, double[] zb) {
int i;
double t = 1, v = 0, t1 = jd / 365250;
for (i = 1; i < 8; i++) {
t *= t1;
v += preceB[i] * t;
}
zb[0] = rad2mrad(zb[0] + (v + 2.9965 * t1) / rad);
}
// ===============光行差==================
private static final double GXC_e[] = { 0.016708634, -0.000042037,
-0.0000001267 }; // 离心率
private static final double GXC_p[] = { 102.93735 / RAD, 1.71946 / RAD,
0.00046 / RAD }; // 近点
private static final dou
