Add a computation of zonal tide effects on UT1 (from IERS conventions).

Plus a Test2 class which tests this on the TAI-UTC difference.

1 files changed, 33 insertions, 0 deletions

diff --git a/org/madore/ephem/Test2.java b/org/madore/ephem/Test2.java
new file mode 100644
index 0000000..e578719
--- /dev/null
+++ b/org/madore/ephem/Test2.java
@@ -0,0 +1,33 @@
+package org.madore.ephem;
+
+import java.io.FileInputStream;
+import java.io.InputStreamReader;
+import java.io.BufferedReader;
+
+public final class Test2 {
+
+    public static void main(String[] args) {
+	Comput.SumPoisson2Terms corr = ZonalTides.getFunc(ZonalTides.Variable.DUT1);
+	try {
+	    // http://data.iers.org/products/214/14443/orig/eopc04_08_IAU2000.62-now
+	    FileInputStream str = new FileInputStream("/tmp/eopc04_08_IAU2000.62-now");
+	    BufferedReader in = new BufferedReader(new InputStreamReader(str, "utf-8"));
+	    String s;
+	    while ( ( s = in.readLine() ) != null ) {
+		String[] fields = s.split("\\s+");
+		if ( fields.length<1 || ! fields[0].matches("\\d{4}") )
+		    continue;
+		int mjd = Integer.parseInt(fields[3]);
+		double utcOffset = Time.utcOffset(mjd, 0);
+		double t = Ephem.fromJd((utcOffset+32.184)/86400. + mjd + 2400000.5);
+		double v = corr.v(t) * 1.e-4;
+		double ut1Offset = Double.parseDouble(fields[6]);
+		double off = ut1Offset - utcOffset;
+		System.out.format("%d\t%.7f\t%.7f\t%.7f\n", mjd, off, v, off-v);
+	    }
+	} catch ( Exception e ) {
+	    throw new RuntimeException(e);
+	}
+    }
+
+}