private EarthOrientationParameters(
JulianDayNumber beginDate, JulianDayNumber endDate,
IReadOnlyList <double> dPsi, IReadOnlyList <double> dEps)
{
BeginDate = beginDate;
EndDate = endDate;
BeginDateHorizons = JulianDayNumber.FromRaw(2437684.5);
this.dPsi = dPsi;
this.dEps = dEps;
}
/// <summary>
/// Load from EOP files
/// <parameter name="eopC04File">File from https://datacenter.iers.org/data/latestVersion/EOP_14_C04_IAU1980_one_file_1962-now.txt</parameter>
/// <parameter name="eopFinalsFile">File from https://datacenter.iers.org/data/latestVersion/finals.all.iau1980.txt</parameter>
/// </summary>
public static EarthOrientationParameters LoadFrom(
Stream eopC04File,
Stream?eopFinalsFile)
{
const double TJDOFS = 2400000.5;
string s;
JulianDayNumber beginDate = default;
var dpsi = new List <double>();
var deps = new List <double>();
int mjdsv = 0;
using (var reader = new StreamReader(eopC04File))
{
while ((s = reader.ReadLine()) != null)
{
if (!s.StartsWith("1962"))
{
continue;
}
var values = s.Split(' ', StringSplitOptions.RemoveEmptyEntries);
var mjd = int.Parse(values[3]);
// is file in one-day steps?
if (mjdsv > 0 && mjd - mjdsv != 1)
{
throw new FormatException("File must be in one-day steps");
}
if (mjdsv == 0)
{
beginDate = JulianDayNumber.FromRaw(mjd + TJDOFS);
}
dpsi.Add(double.Parse(values[8], CultureInfo.InvariantCulture));
deps.Add(double.Parse(values[9], CultureInfo.InvariantCulture));
mjdsv = mjd;
}
}
var endDate = JulianDayNumber.FromRaw(mjdsv + TJDOFS);
// file finals.all may have some more data, and especially estimations for the near future
if (eopFinalsFile != null)
{
mjdsv = 0;
using var reader = new StreamReader(eopFinalsFile);
while ((s = reader.ReadLine()) != null)
{
var mjd = int.Parse(GetDigits(s, 7));
var jd = JulianDayNumber.FromRaw(mjd + TJDOFS);
if (jd <= endDate)
{
continue;
}
// are data in one-day steps?
if (mjdsv > 0 && mjd - mjdsv != 1)
{
throw new FormatException("File must be in one-day steps");
}
// dpsi, deps Bulletin B
var dPsi = GetDoubleFromStr(s, 168);
var dEps = GetDoubleFromStr(s, 178);
if (dPsi == 0.0)
{
// try dpsi, deps Bulletin A
dPsi = GetDoubleFromStr(s, 99);
dEps = GetDoubleFromStr(s, 118);
}
if (dPsi == 0.0)
{
break;
}
dpsi.Add(dPsi / 1000.0);
deps.Add(dEps / 1000.0);
mjdsv = mjd;
}
}
return(new EarthOrientationParameters(beginDate, endDate, dpsi, deps));
}