I'm building an application that will tell your Chinese sign. I looked around but only found charts (from 1900 to 2020), and no logic to create something more dynamic.
Is there no logic for determining a Chinese zodiac?
Does that answer your question:
public string ChineseZodiac(System.DateTime date)
{
System.Globalization.EastAsianLunisolarCalendar cc =
new System.Globalization.ChineseLunisolarCalendar();
int sexagenaryYear = cc.GetSexagenaryYear(date);
int terrestrialBranch = cc.GetTerrestrialBranch(sexagenaryYear);
// string[] years = "rat,ox,tiger,hare,dragon,snake,horse,sheep,monkey,fowl,dog,pig".Split(',');
// string[] years = "Rat,Ox,Tiger,Rabbit,Dragon,Snake,Horse,Goat,Monkey,Rooster,Dog,Pig".Split(',');
// string[] years = new string[]{ "rat", "ox", "tiger", "hare", "dragon", "snake", "horse", "sheep", "monkey", "fowl", "dog", "pig" };
string[] years = new string[]{ "Rat", "Ox", "Tiger", "Rabbit", "Dragon", "Snake", "Horse", "Goat", "Monkey", "Rooster", "Dog", "Pig" };
return years[terrestrialBranch - 1];
} // End Function ChineseZodiac
Fore those that need the source code for another programming language:
I've ripped the corresponding sources out of .NET Framwork, here:
https://gist.github.com/ststeiger/709354299a457e2d79b06d0127096fee
Edit:
I ported this to JavaScript:
"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
exports.ChineseZodiac = void 0;
var DateTimeKind;
(function (DateTimeKind) {
DateTimeKind[DateTimeKind["Unspecified"] = 0] = "Unspecified";
DateTimeKind[DateTimeKind["Utc"] = 1] = "Utc";
DateTimeKind[DateTimeKind["Local"] = 2] = "Local";
})(DateTimeKind || (DateTimeKind = {}));
var GregorianCalendar = (function () {
function GregorianCalendar() {
}
GregorianCalendar.prototype.GetYear = function (time) {
var ticks = time.JavaScriptTicks;
var dt = new Date(ticks);
return dt.getUTCFullYear();
};
GregorianCalendar.prototype.GetMonth = function (time) {
var ticks = time.JavaScriptTicks;
var dt = new Date(ticks);
return (dt.getUTCMonth() + 1);
};
GregorianCalendar.prototype.GetDayOfMonth = function (time) {
var ticks = time.JavaScriptTicks;
var dt = new Date(ticks);
return dt.getUTCDate();
};
return GregorianCalendar;
}());
var DotNetDateTime = (function () {
function DotNetDateTime(ticks, dt) {
this.m_ticks = 0;
this.m_ticks = ticks;
}
DotNetDateTime.fromJsDate = function (dt) {
var jsTicks = dt.getTime();
var dotNetJsbaseTicks = 621355968000000000;
var tenK = 10000;
var dotTicks = dotNetJsbaseTicks + jsTicks * tenK;
return new DotNetDateTime(dotTicks, DateTimeKind.Unspecified);
};
Object.defineProperty(DotNetDateTime.prototype, "Ticks", {
get: function () {
return this.m_ticks;
},
enumerable: false,
configurable: true
});
Object.defineProperty(DotNetDateTime.prototype, "JavaScriptTicks", {
get: function () {
var dotNetJsbaseTicks = 621355968000000000;
var dotNetTicksSince1970 = this.m_ticks - dotNetJsbaseTicks;
var jsTicks = parseInt((dotNetTicksSince1970 / 10000).toString(), 10);
return jsTicks;
},
enumerable: false,
configurable: true
});
return DotNetDateTime;
}());
var MinLunisolarYear = 1901;
var MaxLunisolarYear = 2100;
var DaysPerYear = 365;
var DaysPer4Years = DaysPerYear * 4 + 1;
var DaysPer100Years = DaysPer4Years * 25 - 1;
var DaysPer400Years = DaysPer100Years * 4 + 1;
var DaysTo10000 = DaysPer400Years * 25 - 366;
var TicksPerMillisecond = 10000;
var TicksPerSecond = TicksPerMillisecond * 1000;
var TicksPerMinute = TicksPerSecond * 60;
var TicksPerHour = TicksPerMinute * 60;
var TicksPerDay = TicksPerHour * 24;
var MinTicks = 0;
var MaxTicks = DaysTo10000 * TicksPerDay - 1;
var MinValue = new DotNetDateTime(MinTicks, DateTimeKind.Unspecified);
var MaxValue = new DotNetDateTime(MaxTicks, DateTimeKind.Unspecified);
var Jan1Month = 1;
var Jan1Date = 2;
var nDaysPerMonth = 3;
var s_daysToMonth365 = [0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334];
var s_daysToMonth366 = [0, 31, 60, 91, 121, 152, 182, 213, 244, 274, 305, 335];
var s_yinfo = [
[0, 2, 19, 19168],
[0, 2, 8, 42352],
[5, 1, 29, 21096],
[0, 2, 16, 53856],
[0, 2, 4, 55632],
[4, 1, 25, 27304],
[0, 2, 13, 22176],
[0, 2, 2, 39632],
[2, 1, 22, 19176],
[0, 2, 10, 19168],
[6, 1, 30, 42200],
[0, 2, 18, 42192],
[0, 2, 6, 53840],
[5, 1, 26, 54568],
[0, 2, 14, 46400],
[0, 2, 3, 54944],
[2, 1, 23, 38608],
[0, 2, 11, 38320],
[7, 2, 1, 18872],
[0, 2, 20, 18800],
[0, 2, 8, 42160],
[5, 1, 28, 45656],
[0, 2, 16, 27216],
[0, 2, 5, 27968],
[4, 1, 24, 44456],
[0, 2, 13, 11104],
[0, 2, 2, 38256],
[2, 1, 23, 18808],
[0, 2, 10, 18800],
[6, 1, 30, 25776],
[0, 2, 17, 54432],
[0, 2, 6, 59984],
[5, 1, 26, 27976],
[0, 2, 14, 23248],
[0, 2, 4, 11104],
[3, 1, 24, 37744],
[0, 2, 11, 37600],
[7, 1, 31, 51560],
[0, 2, 19, 51536],
[0, 2, 8, 54432],
[6, 1, 27, 55888],
[0, 2, 15, 46416],
[0, 2, 5, 22176],
[4, 1, 25, 43736],
[0, 2, 13, 9680],
[0, 2, 2, 37584],
[2, 1, 22, 51544],
[0, 2, 10, 43344],
[7, 1, 29, 46248],
[0, 2, 17, 27808],
[0, 2, 6, 46416],
[5, 1, 27, 21928],
[0, 2, 14, 19872],
[0, 2, 3, 42416],
[3, 1, 24, 21176],
[0, 2, 12, 21168],
[8, 1, 31, 43344],
[0, 2, 18, 59728],
[0, 2, 8, 27296],
[6, 1, 28, 44368],
[0, 2, 15, 43856],
[0, 2, 5, 19296],
[4, 1, 25, 42352],
[0, 2, 13, 42352],
[0, 2, 2, 21088],
[3, 1, 21, 59696],
[0, 2, 9, 55632],
[7, 1, 30, 23208],
[0, 2, 17, 22176],
[0, 2, 6, 38608],
[5, 1, 27, 19176],
[0, 2, 15, 19152],
[0, 2, 3, 42192],
[4, 1, 23, 53864],
[0, 2, 11, 53840],
[8, 1, 31, 54568],
[0, 2, 18, 46400],
[0, 2, 7, 46752],
[6, 1, 28, 38608],
[0, 2, 16, 38320],
[0, 2, 5, 18864],
[4, 1, 25, 42168],
[0, 2, 13, 42160],
[10, 2, 2, 45656],
[0, 2, 20, 27216],
[0, 2, 9, 27968],
[6, 1, 29, 44448],
[0, 2, 17, 43872],
[0, 2, 6, 38256],
[5, 1, 27, 18808],
[0, 2, 15, 18800],
[0, 2, 4, 25776],
[3, 1, 23, 27216],
[0, 2, 10, 59984],
[8, 1, 31, 27432],
[0, 2, 19, 23232],
[0, 2, 7, 43872],
[5, 1, 28, 37736],
[0, 2, 16, 37600],
[0, 2, 5, 51552],
[4, 1, 24, 54440],
[0, 2, 12, 54432],
[0, 2, 1, 55888],
[2, 1, 22, 23208],
[0, 2, 9, 22176],
[7, 1, 29, 43736],
[0, 2, 18, 9680],
[0, 2, 7, 37584],
[5, 1, 26, 51544],
[0, 2, 14, 43344],
[0, 2, 3, 46240],
[4, 1, 23, 46416],
[0, 2, 10, 44368],
[9, 1, 31, 21928],
[0, 2, 19, 19360],
[0, 2, 8, 42416],
[6, 1, 28, 21176],
[0, 2, 16, 21168],
[0, 2, 5, 43312],
[4, 1, 25, 29864],
[0, 2, 12, 27296],
[0, 2, 1, 44368],
[2, 1, 22, 19880],
[0, 2, 10, 19296],
[6, 1, 29, 42352],
[0, 2, 17, 42208],
[0, 2, 6, 53856],
[5, 1, 26, 59696],
[0, 2, 13, 54576],
[0, 2, 3, 23200],
[3, 1, 23, 27472],
[0, 2, 11, 38608],
[11, 1, 31, 19176],
[0, 2, 19, 19152],
[0, 2, 8, 42192],
[6, 1, 28, 53848],
[0, 2, 15, 53840],
[0, 2, 4, 54560],
[5, 1, 24, 55968],
[0, 2, 12, 46496],
[0, 2, 1, 22224],
[2, 1, 22, 19160],
[0, 2, 10, 18864],
[7, 1, 30, 42168],
[0, 2, 17, 42160],
[0, 2, 6, 43600],
[5, 1, 26, 46376],
[0, 2, 14, 27936],
[0, 2, 2, 44448],
[3, 1, 23, 21936],
[0, 2, 11, 37744],
[8, 2, 1, 18808],
[0, 2, 19, 18800],
[0, 2, 8, 25776],
[6, 1, 28, 27216],
[0, 2, 15, 59984],
[0, 2, 4, 27296],
[4, 1, 24, 43872],
[0, 2, 12, 43744],
[0, 2, 2, 37600],
[3, 1, 21, 51568],
[0, 2, 9, 51552],
[7, 1, 29, 54440],
[0, 2, 17, 54432],
[0, 2, 5, 55888],
[5, 1, 26, 23208],
[0, 2, 14, 22176],
[0, 2, 3, 42704],
[4, 1, 23, 21224],
[0, 2, 11, 21200],
[8, 1, 31, 43352],
[0, 2, 19, 43344],
[0, 2, 7, 46240],
[6, 1, 27, 46416],
[0, 2, 15, 44368],
[0, 2, 5, 21920],
[4, 1, 24, 42448],
[0, 2, 12, 42416],
[0, 2, 2, 21168],
[3, 1, 22, 43320],
[0, 2, 9, 26928],
[7, 1, 29, 29336],
[0, 2, 17, 27296],
[0, 2, 6, 44368],
[5, 1, 26, 19880],
[0, 2, 14, 19296],
[0, 2, 3, 42352],
[4, 1, 24, 21104],
[0, 2, 10, 53600],
[8, 1, 30, 59696],
[0, 2, 18, 54560],
[0, 2, 7, 55968],
[6, 1, 27, 27472],
[0, 2, 15, 22224],
[0, 2, 5, 19168],
[4, 1, 25, 42216],
[0, 2, 12, 41680],
[0, 2, 1, 53584],
[2, 1, 21, 55592],
[0, 2, 9, 54560],
];
function GregorianIsLeapYear(y) {
if ((y % 4) != 0) {
return false;
}
if ((y % 100) != 0) {
return true;
}
return (y % 400) == 0;
}
function GetYearInfo(lunarYear, index) {
if (lunarYear < MinLunisolarYear || lunarYear > MaxLunisolarYear) {
throw new Error("year");
}
return s_yinfo[lunarYear - MinLunisolarYear][index];
}
function CheckTicksRange(ticks) {
if (ticks < MinValue.Ticks || ticks > MaxValue.Ticks) {
throw new Error("time");
}
}
function GregorianToLunar(solarYear, solarMonth, solarDate) {
var outData = { lunarYear: 0, lunarMonth: 0, lunarDate: 0 };
var isLeapYear = GregorianIsLeapYear(solarYear);
var jan1Month;
var jan1Date;
var solarDay = isLeapYear ? s_daysToMonth366[solarMonth - 1] : s_daysToMonth365[solarMonth - 1];
solarDay += solarDate;
var lunarDay = solarDay;
outData.lunarYear = solarYear;
if (outData.lunarYear == (MaxLunisolarYear + 1)) {
outData.lunarYear--;
lunarDay += (GregorianIsLeapYear(outData.lunarYear) ? 366 : 365);
jan1Month = GetYearInfo(outData.lunarYear, Jan1Month);
jan1Date = GetYearInfo(outData.lunarYear, Jan1Date);
}
else {
jan1Month = GetYearInfo(outData.lunarYear, Jan1Month);
jan1Date = GetYearInfo(outData.lunarYear, Jan1Date);
if ((solarMonth < jan1Month) ||
(solarMonth == jan1Month && solarDate < jan1Date)) {
outData.lunarYear--;
lunarDay += (GregorianIsLeapYear(outData.lunarYear) ? 366 : 365);
jan1Month = GetYearInfo(outData.lunarYear, Jan1Month);
jan1Date = GetYearInfo(outData.lunarYear, Jan1Date);
}
}
lunarDay -= s_daysToMonth365[jan1Month - 1];
lunarDay -= (jan1Date - 1);
var mask = 0x8000;
var yearInfo = GetYearInfo(outData.lunarYear, nDaysPerMonth);
var days = ((yearInfo & mask) != 0) ? 30 : 29;
outData.lunarMonth = 1;
while (lunarDay > days) {
lunarDay -= days;
outData.lunarMonth++;
mask >>= 1;
days = ((yearInfo & mask) != 0) ? 30 : 29;
}
outData.lunarDate = lunarDay;
return outData;
}
function TimeToLunar(time) {
var gregorianCalendar = new GregorianCalendar();
var gy = gregorianCalendar.GetYear(time);
var gm = gregorianCalendar.GetMonth(time);
var gd = gregorianCalendar.GetDayOfMonth(time);
var ad = GregorianToLunar(gy, gm, gd);
return {
year: ad.lunarYear
};
}
function GetSexagenaryYear(time) {
CheckTicksRange(time.Ticks);
var x = TimeToLunar(time);
return ((x.year - 4) % 60) + 1;
}
function GetTerrestrialBranch(sexagenaryYear) {
if (sexagenaryYear < 1 || sexagenaryYear > 60) {
throw new Error("sexagenaryYear");
}
return ((sexagenaryYear - 1) % 12) + 1;
}
function ChineseZodiac(date) {
var dotNetDate = DotNetDateTime.fromJsDate(date);
var sexagenaryYear = GetSexagenaryYear(dotNetDate);
var terrestrialBranch = GetTerrestrialBranch(sexagenaryYear);
var years = ["Rat", "Ox", "Tiger", "Rabbit", "Dragon", "Snake", "Horse", "Goat", "Monkey", "Rooster", "Dog", "Pig"];
return years[terrestrialBranch - 1];
}
exports.ChineseZodiac = ChineseZodiac;
Testing:
var exports = {};
// [copy-pasting above code]
exports.ChineseZodiac(new Date(1970,0,1))
exports.ChineseZodiac(new Date(2021,0,1))
exports.ChineseZodiac(new Date(2022,0,1))
all returns the same values as dotnet.