/*
program: leap1
description: test for leap year accuracy, adjusts for Earth's rotational rate,
assumed to be constantly decreasing.
Gregorian calendar method is more accurate thru year 100,000
Whereas, a modulo 128 method accumulates 31 days of error in 100,000 years.
maw
makerun leap1 50000 100000
adding: leap1.class (in=1663) (out=938) (deflated 43%)
Year = 50000
Days Float0 = 1.8262178498500004E7
Days Float1 = 1.8262178353000224E7
Days Gregorian = 18262125
Days intDays1 = 18262110
Year = 100000
Days Float0 = 3.652450699700001E7
Days Float1 = 3.652450670599856E7
Days Gregorian = 36524250
Days intDays1 = 36524219
*/
import java.io.*;
public class leap1
{
static double earthRotationsPerYear0 = 365.24207;
static double earthRotationsYearIncrement = 0.00000006;
static double earthRotations100YearIncrement = 0.000006;
private static void leapTest( long yearModulo, long yearStop) {
long intDays0 = 0;
long intDays1 = 0;
double floatDays0 = 0.0;
double floatDays1 = 0.0;
double floatDays1PerYearIncrement = earthRotationsPerYear0;
for( long i=0; i<yearStop; i++) {
floatDays0 += earthRotationsPerYear0 + (i * earthRotationsYearIncrement);
if ((( i+1) % 100) == 0)
floatDays1PerYearIncrement += earthRotations100YearIncrement;
floatDays1 += floatDays1PerYearIncrement;
intDays0 += 365;
if ((( i+1) % 4) == 0) {
if ((( i+1) % 100) != 0)
intDays0++;
else if ((( i+1) % 400) == 0)
intDays0++;
}
intDays1 += 365;
if ( ((( i+1) % 4) == 0) &&
((( i+1) % 128) != 0) )
intDays1++;
if ((( i+1) % yearModulo) == 0) {
System.out.println( " Year = " + (i+1) );
System.out.println( " Days Float0 = " + floatDays0 );
System.out.println( " Days Float1 = " + floatDays1 );
System.out.println( " Days Gregorian = " + intDays0 );
System.out.println( " Days intDays1 = " + intDays1 );
}
} // end for
} // end leapTest
public static void main(String[] args) {
if (args.length != 2) {
System.err.println("Usage: java leap1 " +
"<year modulo> <year end>");
}
else {
try {
leapTest( Long.parseLong( args[0], 10), Long.parseLong( args[1], 10) );
} catch (Exception e) {
System.err.println(
"Exception Error:" + e.getMessage());
}
}
}
} // End of public class leap1
