# HG changeset patch
# User Sascha L. Teichmann <sascha.teichmann@intevation.de>
# Date 1340692417 0
# Node ID 585c0b49e696cd97531a89a6f1dd94082f6eb202
# Parent  cbaa49896eca935435ee7f4bdd060a1ecc7c49af
Added inverses of the fitting functions.

flys-artifacts/trunk@4792 c6561f87-3c4e-4783-a992-168aeb5c3f6f

diff -r cbaa49896eca -r 585c0b49e696 flys-artifacts/ChangeLog
--- a/flys-artifacts/ChangeLog	Mon Jun 25 19:13:16 2012 +0000
+++ b/flys-artifacts/ChangeLog	Tue Jun 26 06:33:37 2012 +0000
@@ -1,3 +1,31 @@
+2012-06-26	Sascha L. Teichmann	<sascha.teichmann@intevation.de>
+
+	Implemenation of the inverses of the fitting functions. Needed
+	for the AT export of the calculated curves.
+
+	* src/main/java/de/intevation/flys/artifacts/math/fitting/Function.java:
+	  Added abstract method getInverse() to get the inverse of the
+	  function.
+
+	* src/main/java/de/intevation/flys/artifacts/math/fitting/Pow.java,
+	  src/main/java/de/intevation/flys/artifacts/math/fitting/SQPow.java,
+	  src/main/java/de/intevation/flys/artifacts/math/fitting/Linear.java,
+	  src/main/java/de/intevation/flys/artifacts/math/fitting/LogLinear.java,
+	  src/main/java/de/intevation/flys/artifacts/math/fitting/Log.java,
+	  src/main/java/de/intevation/flys/artifacts/math/fitting/Quad.java,
+	  src/main/java/de/intevation/flys/artifacts/math/fitting/Exp.java:
+	  Implements the getInverse() method.
+
+	* src/main/java/de/intevation/flys/artifacts/math/fitting/InvLog.java,
+	  src/main/java/de/intevation/flys/artifacts/math/fitting/InvLogLinear.java,
+	  src/main/java/de/intevation/flys/artifacts/math/fitting/InvQuad.java,
+	  src/main/java/de/intevation/flys/artifacts/math/fitting/InvPow.java,
+	  src/main/java/de/intevation/flys/artifacts/math/fitting/InvExp.java,
+	  src/main/java/de/intevation/flys/artifacts/math/fitting/InvSQPow.java,
+	  src/main/java/de/intevation/flys/artifacts/math/fitting/InvLinear.java:
+	  Implements the inverses of the function above. Some are still
+	  stubs.
+
 2012-06-25	Felix Wolfsteller	<felix.wolfsteller@intevation.de>
 
 	Fix issue663 ("step" curves for Q).
diff -r cbaa49896eca -r 585c0b49e696 flys-artifacts/src/main/java/de/intevation/flys/artifacts/math/fitting/Exp.java
--- a/flys-artifacts/src/main/java/de/intevation/flys/artifacts/math/fitting/Exp.java	Mon Jun 25 19:13:16 2012 +0000
+++ b/flys-artifacts/src/main/java/de/intevation/flys/artifacts/math/fitting/Exp.java	Tue Jun 26 06:33:37 2012 +0000
@@ -10,18 +10,21 @@
         public de.intevation.flys.artifacts.math.Function
             instantiate(double [] parameters)
         {
-            final double m = parameters[0];
-            final double a = parameters[1];
+                  double m     = parameters[0];
+            final double a     = parameters[1];
+            final double logam = Math.log(a)*m;
 
             return new de.intevation.flys.artifacts.math.Function() {
                 @Override
                 public double value(double Q) {
-                    return Math.pow(a, Q)*Math.log(a)*m;
+                    return Math.pow(a, Q)*logam;
                 }
             };
         }
     };
 
+    public static final Function INSTANCE = new Exp();
+
     public Exp() {
         super(
             "exp",
@@ -47,5 +50,10 @@
     public Derivative getDerivative() {
         return DERIVATIVE;
     }
+
+    @Override
+    public Function getInverse() {
+        return InvExp.INSTANCE;
+    }
 }
 // vim:set ts=4 sw=4 si et sta sts=4 fenc=utf8 :
diff -r cbaa49896eca -r 585c0b49e696 flys-artifacts/src/main/java/de/intevation/flys/artifacts/math/fitting/Function.java
--- a/flys-artifacts/src/main/java/de/intevation/flys/artifacts/math/fitting/Function.java	Mon Jun 25 19:13:16 2012 +0000
+++ b/flys-artifacts/src/main/java/de/intevation/flys/artifacts/math/fitting/Function.java	Tue Jun 26 06:33:37 2012 +0000
@@ -94,5 +94,7 @@
     }
 
     public abstract Derivative getDerivative();
+
+    public abstract Function getInverse();
 }
 // vim:set ts=4 sw=4 si et sta sts=4 fenc=utf8 :
diff -r cbaa49896eca -r 585c0b49e696 flys-artifacts/src/main/java/de/intevation/flys/artifacts/math/fitting/InvExp.java
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/flys-artifacts/src/main/java/de/intevation/flys/artifacts/math/fitting/InvExp.java	Tue Jun 26 06:33:37 2012 +0000
@@ -0,0 +1,66 @@
+package de.intevation.flys.artifacts.math.fitting;
+
+public class InvExp
+extends      Function
+{
+    public static final Derivative DERIVATIVE =
+        new Derivative("W'(Q) = 1/(log(a)*(Q-b))") {
+
+        @Override
+        public de.intevation.flys.artifacts.math.Function
+            instantiate(double [] parameters)
+        {
+            final double a = parameters[1];
+            final double b = parameters[2];
+            final double loga = Math.log(a);
+
+            return new de.intevation.flys.artifacts.math.Function() {
+                @Override
+                public double value(double Q) {
+                    return 1d/(loga*(Q-a));
+                }
+            };
+        }
+    };
+
+    public static final Function INSTANCE = new InvExp();
+
+    public InvExp() {
+        super(
+            "inv-exp",
+            "Q(W) = log((W-b)/m)/log(a)",
+            new String [] { "m", "a", "b" });
+    }
+
+    @Override
+    public double value(double W, double [] parameters) {
+        double m = parameters[0];
+        double a = parameters[1];
+        double b = parameters[2];
+        return Math.log((W-b)/m)/Math.log(a);
+    }
+
+    @Override
+    public double [] gradient(double Q, double [] parameters) {
+        double m = parameters[0];
+        double a = parameters[1];
+        double b = parameters[2];
+        double loga = Math.log(a);
+        return new double [] {
+            -1d/(loga*m),
+            -Math.log((Q-b)/m)/(a*loga*loga),
+            -1d/(loga*(Q-b))
+        };
+    }
+
+    @Override
+    public Derivative getDerivative() {
+        return DERIVATIVE;
+    }
+
+    @Override
+    public Function getInverse() {
+        return Exp.INSTANCE;
+    }
+}
+// vim:set ts=4 sw=4 si et sta sts=4 fenc=utf8 :
diff -r cbaa49896eca -r 585c0b49e696 flys-artifacts/src/main/java/de/intevation/flys/artifacts/math/fitting/InvLinear.java
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/flys-artifacts/src/main/java/de/intevation/flys/artifacts/math/fitting/InvLinear.java	Tue Jun 26 06:33:37 2012 +0000
@@ -0,0 +1,57 @@
+package de.intevation.flys.artifacts.math.fitting;
+
+public class InvLinear
+extends      Function
+{
+    public static Function INSTANCE = new InvLinear();
+
+    public static final Derivative DERIVATIVE =
+        new Derivative("Q'(W) = 1/m") {
+
+        @Override
+        public de.intevation.flys.artifacts.math.Function
+            instantiate(double [] parameters)
+        {
+            final double _1m = 1d/parameters[0];
+
+            return new de.intevation.flys.artifacts.math.Function() {
+                @Override
+                public double value(double Q) {
+                    return _1m;
+                }
+            };
+        }
+    };
+
+    public InvLinear() {
+        super("inv-linear", "W(Q) = (Q-b)/m", new String [] { "m", "b" });
+    }
+
+    @Override
+    public double value(double Q, double [] parameters) {
+        double m = parameters[0];
+        double b = parameters[1];
+        return (Q-b)/m;
+    }
+
+    @Override
+    public double [] gradient(double Q, double [] parameters) {
+        double m = parameters[0];
+        double b = parameters[1];
+        return new double [] {
+            -(Q-b)/(m*m),
+            -1d/m
+        };
+    }
+
+    @Override
+    public Derivative getDerivative() {
+        return DERIVATIVE;
+    }
+
+    @Override
+    public Function getInverse() {
+        return Linear.INSTANCE;
+    }
+}
+// vim:set ts=4 sw=4 si et sta sts=4 fenc=utf8 :
diff -r cbaa49896eca -r 585c0b49e696 flys-artifacts/src/main/java/de/intevation/flys/artifacts/math/fitting/InvLog.java
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/flys-artifacts/src/main/java/de/intevation/flys/artifacts/math/fitting/InvLog.java	Tue Jun 26 06:33:37 2012 +0000
@@ -0,0 +1,56 @@
+package de.intevation.flys.artifacts.math.fitting;
+
+public class InvLog
+extends      Function
+{
+    public static final Derivative DERIVATIVE =
+        new Derivative("Q'(W) = exp(W/m)/m") {
+
+        @Override
+        public de.intevation.flys.artifacts.math.Function
+            instantiate(double [] parameters)
+        {
+            final double _1m = 1d / parameters[0];
+
+            return new de.intevation.flys.artifacts.math.Function() {
+                @Override
+                public double value(double W) {
+                    return Math.exp(W*_1m)*_1m;
+                }
+            };
+        }
+    };
+
+    public static final Function INSTANCE = new InvLog();
+
+    public InvLog() {
+        super("inv-log",  "Q(W) = e^(W/m) - b", new String [] { "m", "b" });
+    }
+
+    @Override
+    public double value(double w, double [] parameters) {
+        double m = parameters[0];
+        double b = parameters[1];
+        return Math.exp(w/m) - b;
+    }
+
+    @Override
+    public double [] gradient(double w, double [] parameters) {
+        double m   = parameters[0];
+        double b   = parameters[1];
+        double ewm = Math.exp(w/m);
+        return new double [] { -w*ewm/(m*m), -1 };
+    }
+
+    @Override
+    public Derivative getDerivative() {
+        return DERIVATIVE;
+    }
+
+    @Override
+    public Function getInverse() {
+        return Log.INSTANCE;
+    }
+}
+// vim:set ts=4 sw=4 si et sta sts=4 fenc=utf8 :
+
diff -r cbaa49896eca -r 585c0b49e696 flys-artifacts/src/main/java/de/intevation/flys/artifacts/math/fitting/InvLogLinear.java
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/flys-artifacts/src/main/java/de/intevation/flys/artifacts/math/fitting/InvLogLinear.java	Tue Jun 26 06:33:37 2012 +0000
@@ -0,0 +1,36 @@
+package de.intevation.flys.artifacts.math.fitting;
+
+public class InvLogLinear
+extends      Function
+{
+    public static final Function INSTANCE = new InvLogLinear();
+
+    public InvLogLinear() {
+        // TODO: Implement me!
+    }
+
+    @Override
+    public double value(double W, double [] parameters) {
+        // TODO: Implement me!
+        return 0d;
+    }
+
+    @Override
+    public double [] gradient(double Q, double [] parameters) {
+        // TODO: Implement me!
+        return null;
+    }
+
+    @Override
+    public Derivative getDerivative() {
+        // TODO: Implement me!
+        return null;
+    }
+
+    @Override
+    public Function getInverse() {
+        // TODO: Implement me!
+        return null;
+    }
+}
+// vim:set ts=4 sw=4 si et sta sts=4 fenc=utf8 :
diff -r cbaa49896eca -r 585c0b49e696 flys-artifacts/src/main/java/de/intevation/flys/artifacts/math/fitting/InvPow.java
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/flys-artifacts/src/main/java/de/intevation/flys/artifacts/math/fitting/InvPow.java	Tue Jun 26 06:33:37 2012 +0000
@@ -0,0 +1,36 @@
+package de.intevation.flys.artifacts.math.fitting;
+
+public class InvPow
+extends      Function
+{
+    public static final Function INSTANCE = new InvPow();
+
+    public InvPow() {
+        // TODO: Implement me!
+    }
+
+    @Override
+    public double value(double W, double [] parameters) {
+        // TODO: Implement me!
+        return 0d;
+    }
+
+    @Override
+    public double [] gradient(double Q, double [] parameters) {
+        // TODO: Implement me!
+        return null;
+    }
+
+    @Override
+    public Derivative getDerivative() {
+        // TODO: Implement me!
+        return null;
+    }
+
+    @Override
+    public Function getInverse() {
+        // TODO: Implement me!
+        return null;
+    }
+}
+// vim:set ts=4 sw=4 si et sta sts=4 fenc=utf8 :
diff -r cbaa49896eca -r 585c0b49e696 flys-artifacts/src/main/java/de/intevation/flys/artifacts/math/fitting/InvQuad.java
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/flys-artifacts/src/main/java/de/intevation/flys/artifacts/math/fitting/InvQuad.java	Tue Jun 26 06:33:37 2012 +0000
@@ -0,0 +1,36 @@
+package de.intevation.flys.artifacts.math.fitting;
+
+public class InvQuad
+extends      Function
+{
+    public static final Function INSTANCE = new InvQuad();
+
+    public InvQuad() {
+        // TODO: Implement me!
+    }
+
+    @Override
+    public double value(double W, double [] parameters) {
+        // TODO: Implement me!
+        return 0d;
+    }
+
+    @Override
+    public double [] gradient(double Q, double [] parameters) {
+        // TODO: Implement me!
+        return null;
+    }
+
+    @Override
+    public Derivative getDerivative() {
+        // TODO: Implement me!
+        return null;
+    }
+
+    @Override
+    public Function getInverse() {
+        // TODO: Implement me!
+        return null;
+    }
+}
+// vim:set ts=4 sw=4 si et sta sts=4 fenc=utf8 :
diff -r cbaa49896eca -r 585c0b49e696 flys-artifacts/src/main/java/de/intevation/flys/artifacts/math/fitting/InvSQPow.java
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/flys-artifacts/src/main/java/de/intevation/flys/artifacts/math/fitting/InvSQPow.java	Tue Jun 26 06:33:37 2012 +0000
@@ -0,0 +1,36 @@
+package de.intevation.flys.artifacts.math.fitting;
+
+public class InvSQPow
+extends      Function
+{
+    public static final Function INSTANCE = new InvSQPow();
+
+    public InvSQPow() {
+        // TODO: Implement me!
+    }
+
+    @Override
+    public double value(double W, double [] parameters) {
+        // TODO: Implement me!
+        return 0d;
+    }
+
+    @Override
+    public double [] gradient(double Q, double [] parameters) {
+        // TODO: Implement me!
+        return null;
+    }
+
+    @Override
+    public Derivative getDerivative() {
+        // TODO: Implement me!
+        return null;
+    }
+
+    @Override
+    public Function getInverse() {
+        // TODO: Implement me!
+        return null;
+    }
+}
+// vim:set ts=4 sw=4 si et sta sts=4 fenc=utf8 :
diff -r cbaa49896eca -r 585c0b49e696 flys-artifacts/src/main/java/de/intevation/flys/artifacts/math/fitting/Linear.java
--- a/flys-artifacts/src/main/java/de/intevation/flys/artifacts/math/fitting/Linear.java	Mon Jun 25 19:13:16 2012 +0000
+++ b/flys-artifacts/src/main/java/de/intevation/flys/artifacts/math/fitting/Linear.java	Tue Jun 26 06:33:37 2012 +0000
@@ -21,6 +21,8 @@
         }
     };
 
+    public static final Function INSTANCE = new Linear();
+
     public Linear() {
         super("linear", "W(Q) = m*Q + b", new String [] { "m", "b" });
     }
@@ -39,5 +41,10 @@
     public Derivative getDerivative() {
         return DERIVATIVE;
     }
+
+    @Override
+    public Function getInverse() {
+        return InvLinear.INSTANCE;
+    }
 }
 // vim:set ts=4 sw=4 si et sta sts=4 fenc=utf8 :
diff -r cbaa49896eca -r 585c0b49e696 flys-artifacts/src/main/java/de/intevation/flys/artifacts/math/fitting/Log.java
--- a/flys-artifacts/src/main/java/de/intevation/flys/artifacts/math/fitting/Log.java	Mon Jun 25 19:13:16 2012 +0000
+++ b/flys-artifacts/src/main/java/de/intevation/flys/artifacts/math/fitting/Log.java	Tue Jun 26 06:33:37 2012 +0000
@@ -22,6 +22,8 @@
         }
     };
 
+    public static final Function INSTANCE = new Log();
+
     public Log() {
         super("log",  "W(Q) = m*ln(Q + b)", new String [] { "m", "b" });
     }
@@ -46,5 +48,10 @@
     public Derivative getDerivative() {
         return DERIVATIVE;
     }
+
+    @Override
+    public Function getInverse() {
+        return InvLog.INSTANCE;
+    }
 }
 // vim:set ts=4 sw=4 si et sta sts=4 fenc=utf8 :
diff -r cbaa49896eca -r 585c0b49e696 flys-artifacts/src/main/java/de/intevation/flys/artifacts/math/fitting/LogLinear.java
--- a/flys-artifacts/src/main/java/de/intevation/flys/artifacts/math/fitting/LogLinear.java	Mon Jun 25 19:13:16 2012 +0000
+++ b/flys-artifacts/src/main/java/de/intevation/flys/artifacts/math/fitting/LogLinear.java	Tue Jun 26 06:33:37 2012 +0000
@@ -54,5 +54,10 @@
     public Derivative getDerivative() {
         return DERIVATIVE;
     }
+
+    @Override
+    public Function getInverse() {
+        return InvLogLinear.INSTANCE;
+    }
 }
 // vim:set ts=4 sw=4 si et sta sts=4 fenc=utf8 :
diff -r cbaa49896eca -r 585c0b49e696 flys-artifacts/src/main/java/de/intevation/flys/artifacts/math/fitting/Pow.java
--- a/flys-artifacts/src/main/java/de/intevation/flys/artifacts/math/fitting/Pow.java	Mon Jun 25 19:13:16 2012 +0000
+++ b/flys-artifacts/src/main/java/de/intevation/flys/artifacts/math/fitting/Pow.java	Tue Jun 26 06:33:37 2012 +0000
@@ -50,5 +50,10 @@
     public Derivative getDerivative() {
         return DERIVATIVE;
     }
+
+    @Override
+    public Function getInverse() {
+        return InvPow.INSTANCE;
+    }
 }
 // vim:set ts=4 sw=4 si et sta sts=4 fenc=utf8 :
diff -r cbaa49896eca -r 585c0b49e696 flys-artifacts/src/main/java/de/intevation/flys/artifacts/math/fitting/Quad.java
--- a/flys-artifacts/src/main/java/de/intevation/flys/artifacts/math/fitting/Quad.java	Mon Jun 25 19:13:16 2012 +0000
+++ b/flys-artifacts/src/main/java/de/intevation/flys/artifacts/math/fitting/Quad.java	Tue Jun 26 06:33:37 2012 +0000
@@ -44,5 +44,10 @@
     public Derivative getDerivative() {
         return DERIVATIVE;
     }
+
+    @Override
+    public Function getInverse() {
+        return InvQuad.INSTANCE;
+    }
 }
 // vim:set ts=4 sw=4 si et sta sts=4 fenc=utf8 :
diff -r cbaa49896eca -r 585c0b49e696 flys-artifacts/src/main/java/de/intevation/flys/artifacts/math/fitting/SQPow.java
--- a/flys-artifacts/src/main/java/de/intevation/flys/artifacts/math/fitting/SQPow.java	Mon Jun 25 19:13:16 2012 +0000
+++ b/flys-artifacts/src/main/java/de/intevation/flys/artifacts/math/fitting/SQPow.java	Tue Jun 26 06:33:37 2012 +0000
@@ -49,5 +49,10 @@
     public Derivative getDerivative() {
         return DERIVATIVE;
     }
+
+    @Override
+    public Function getInverse() {
+        return InvSQPow.INSTANCE;
+    }
 }
 // vim:set ts=4 sw=4 si et sta sts=4 fenc=utf8 :