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authorDavid A. Madore <david+git@madore.org>2012-03-27 14:48:27 (GMT)
committerDavid A. Madore <david+git@madore.org>2012-03-27 17:39:42 (GMT)
commitf3b19e381097c01c1abb119e91487191d7e2ef5e (patch)
tree6eb6e804528ac097d4db217d2e32296c03cbf466
parent2ee3f055058d10ec7a50182e102ba0a235878f71 (diff)
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Implement more general Poisson series.
-rw-r--r--org/madore/ephem/Comput.java91
1 files changed, 77 insertions, 14 deletions
diff --git a/org/madore/ephem/Comput.java b/org/madore/ephem/Comput.java
index 214d5e8..77e305b 100644
--- a/org/madore/ephem/Comput.java
+++ b/org/madore/ephem/Comput.java
@@ -1,7 +1,7 @@
package org.madore.ephem;
import java.util.List;
-import java.util.ArrayList;
+import java.util.HashMap;
import java.util.Arrays;
public final class Comput {
@@ -75,7 +75,7 @@ public final class Comput {
for ( int i=0 ; i<tms.size() ; i++ )
z += tms.get(i).v(t);
return z;
- }
+ }
}
public static class LinCombFunction implements Function {
@@ -107,7 +107,7 @@ public final class Comput {
for ( int i=0 ; i<tms.size() ; i++ )
z += c.get(i) * tms.get(i).v(t);
return z;
- }
+ }
}
public static final class TimesPower implements Function {
@@ -141,20 +141,83 @@ public final class Comput {
y *= t;
}
return z;
- }
+ }
}
- public static final class PoissonTerm implements Function {
- // Returns c*t^d*cos(phi+om*t) = t^d*(a*cos(om*t) + b*sin(om*t))
+ public static class Poisson2Term implements Function {
+ // Returns c*t^d*cos(phi+sum(om[i]*fn[i](t)))
int deg;
double c;
- double phi;
- double om;
- PoissonTerm(int deg, double c, double phi, double om) {
+ double phi;
+ double[] om;
+ Function[] fn;
+ Poisson2Term(int deg, double c, double phi, double[] om, Function[] fn) {
+ if ( om.length != fn.length )
+ throw new IllegalArgumentException();
this.c = c;
this.deg = deg;
this.phi = phi;
this.om = om;
+ this.fn = fn;
+ }
+ public static Poisson2Term cphi(int deg, double c, double phi, double[] om, Function[] fn) {
+ return new Poisson2Term(deg, c, phi, om, fn);
+ }
+ public static Poisson2Term ab(int deg, double a, double b, double om[], Function[] fn) {
+ double c = Math.sqrt(a*a + b*b);
+ double phi = Math.atan2(-b, a);
+ return new Poisson2Term(deg, c, phi, om, fn);
+ }
+ public double v(double t) {
+ double arg = 0;
+ for ( int i=0 ; i<om.length ; i++ )
+ arg += om[i]*fn[i].v(t);
+ return c * ipow(t, deg) * Math.cos(arg + phi);
+ }
+ }
+
+ public static class SumPoisson2Terms extends SumFunction
+ implements Function {
+ List<? extends Poisson2Term> tms;
+ public SumPoisson2Terms(List<? extends Poisson2Term> tms) {
+ super(tms);
+ this.tms = tms;
+ }
+ public SumPoisson2Terms(Poisson2Term[] tms) {
+ this(Arrays.asList(tms));
+ }
+ public double v(double t) {
+ double z = 0;
+ final int npow = 6;
+ double[] tpow = new double[npow];
+ for ( int d=0 ; d<npow ; d++ )
+ tpow[d] = ipow(t,d);
+ HashMap<Function,Double> fncache = new HashMap<Function,Double>();
+ for ( int i=0 ; i<tms.size() ; i++ ) {
+ Poisson2Term tm = tms.get(i);
+ int deg = tm.deg;
+ double tp = deg<npow ? tpow[deg] : ipow(t,deg);
+ double arg = 0;
+ for ( int j=0 ; j<tm.om.length ; j++ ) {
+ if ( ! fncache.containsKey(tm.fn[j]) ) {
+ double v = tm.fn[j].v(t);
+ fncache.put(tm.fn[j], v);
+ }
+ arg += tm.om[j]*fncache.get(tm.fn[j]);
+ }
+ z += tm.c * tp * Math.cos(arg + tm.phi);
+ }
+ return z;
+ }
+ }
+
+ public static final class PoissonTerm extends Poisson2Term implements Function {
+ // Returns c*t^d*cos(phi+om*t) = t^d*(a*cos(om*t) + b*sin(om*t))
+ double om;
+ private static Function identity = new Identity();
+ PoissonTerm(int deg, double c, double phi, double om) {
+ super(deg, c, phi, new double[] { om }, new Function[] { identity });
+ this.om = om;
}
public static PoissonTerm cphi(int deg, double c, double phi, double om) {
return new PoissonTerm(deg, c, phi, om);
@@ -169,7 +232,7 @@ public final class Comput {
}
}
- public static class SumPoissonTerms extends SumFunction
+ public static class SumPoissonTerms extends SumPoisson2Terms
implements Function {
List<? extends PoissonTerm> tms;
public SumPoissonTerms(List<? extends PoissonTerm> tms) {
@@ -182,17 +245,17 @@ public final class Comput {
public double v(double t) {
double z = 0;
final int npow = 6;
- List<Double> tpow = new ArrayList<Double>(npow);
+ double[] tpow = new double[npow];
for ( int d=0 ; d<npow ; d++ )
- tpow.add(ipow(t,d));
+ tpow[d] = ipow(t,d);
for ( int i=0 ; i<tms.size() ; i++ ) {
PoissonTerm tm = tms.get(i);
int deg = tm.deg;
- double tp = deg<npow ? tpow.get(deg) : ipow(t,deg);
+ double tp = deg<npow ? tpow[deg] : ipow(t,deg);
z += tm.c * tp * Math.cos(tm.om*t + tm.phi);
}
return z;
- }
+ }
}
}