MATH-1362: Use "IntegerSequence.Incrementor".

src/main/java/org/apache/commons/math4/analysis/integration/BaseAbstractUnivariateIntegrator.java

@@ -24,7 +24,7 @@ import org.apache.commons.math4.exception.NotStrictlyPositiveException;
 import org.apache.commons.math4.exception.NullArgumentException;
 import org.apache.commons.math4.exception.NumberIsTooSmallException;
 import org.apache.commons.math4.exception.TooManyEvaluationsException;
-import org.apache.commons.math4.util.Incrementor;
+import org.apache.commons.math4.util.IntegerSequence;
 import org.apache.commons.math4.util.MathUtils;
 
 /**
@@ -46,8 +46,6 @@ public abstract class BaseAbstractUnivariateIntegrator implements UnivariateInte
     /** Default maximal iteration count. */
     public static final int DEFAULT_MAX_ITERATIONS_COUNT = Integer.MAX_VALUE;
 
-    /** The iteration count. */
-    protected final Incrementor iterations;
 
     /** Maximum absolute error. */
     private final double absoluteAccuracy;
@@ -57,9 +55,14 @@ public abstract class BaseAbstractUnivariateIntegrator implements UnivariateInte
 
     /** minimum number of iterations */
     private final int minimalIterationCount;
+    /** maximum number of iterations */
+    private final int maximalIterationCount;
+
+    /** The iteration count. */
+    protected IntegerSequence.Incrementor iterations;
 
     /** The functions evaluation count. */
-    private final Incrementor evaluations;
+    private IntegerSequence.Incrementor evaluations;
 
     /** Function to integrate. */
     private UnivariateFunction function;
@@ -123,12 +126,7 @@ public abstract class BaseAbstractUnivariateIntegrator implements UnivariateInte
             throw new NumberIsTooSmallException(maximalIterationCount, minimalIterationCount, false);
         }
         this.minimalIterationCount = minimalIterationCount;
-        this.iterations            = new Incrementor();
+        this.maximalIterationCount = maximalIterationCount;
-        iterations.setMaximalCount(maximalIterationCount);
-
-        // prepare evaluations counter, but do not set it yet
-        evaluations = new Incrementor();
-
     }
 
     /**
@@ -218,7 +216,7 @@ public abstract class BaseAbstractUnivariateIntegrator implements UnivariateInte
     protected double computeObjectiveValue(final double point)
         throws TooManyEvaluationsException {
         try {
-            evaluations.incrementCount();
+            evaluations.increment();
         } catch (MaxCountExceededException e) {
             throw new TooManyEvaluationsException(e.getMax());
         }
@@ -250,10 +248,10 @@ public abstract class BaseAbstractUnivariateIntegrator implements UnivariateInte
         min = lower;
         max = upper;
         function = f;
-        evaluations.setMaximalCount(maxEval);
+        iterations = IntegerSequence.Incrementor.create()
-        evaluations.resetCount();
+            .withMaximalCount(maximalIterationCount);
-        iterations.resetCount();
+        evaluations = IntegerSequence.Incrementor.create()
-
+            .withMaximalCount(maxEval);
     }
 
     /** {@inheritDoc} */
@@ -268,7 +266,6 @@ public abstract class BaseAbstractUnivariateIntegrator implements UnivariateInte
 
         // Perform computation.
         return doIntegrate();
-
     }
 
     /**

src/main/java/org/apache/commons/math4/analysis/integration/IterativeLegendreGaussIntegrator.java

@@ -142,7 +142,7 @@ public class IterativeLegendreGaussIntegrator
             final double ratio = FastMath.min(4, FastMath.pow(delta / limit, 0.5 / numberOfPoints));
             n = FastMath.max((int) (ratio * n), n + 1);
             oldt = t;
-            iterations.incrementCount();
+            iterations.increment();
         }
     }
 

src/main/java/org/apache/commons/math4/analysis/integration/MidPointIntegrator.java

@@ -150,7 +150,7 @@ public class MidPointIntegrator extends BaseAbstractUnivariateIntegrator {
         double oldt = diff * computeObjectiveValue(midPoint);
 
         while (true) {
-            iterations.incrementCount();
+            iterations.increment();
             final int i = iterations.getCount();
             final double t = stage(i, oldt, min, diff);
             if (i >= getMinimalIterationCount()) {

src/main/java/org/apache/commons/math4/analysis/integration/RombergIntegrator.java

@@ -107,7 +107,7 @@ public class RombergIntegrator extends BaseAbstractUnivariateIntegrator {
 
         TrapezoidIntegrator qtrap = new TrapezoidIntegrator();
         currentRow[0] = qtrap.stage(this, 0);
-        iterations.incrementCount();
+        iterations.increment();
         double olds = currentRow[0];
         while (true) {
 
@@ -119,7 +119,7 @@ public class RombergIntegrator extends BaseAbstractUnivariateIntegrator {
             currentRow = tmpRow;
 
             currentRow[0] = qtrap.stage(this, i);
-            iterations.incrementCount();
+            iterations.increment();
             for (int j = 1; j <= i; j++) {
                 // Richardson extrapolation coefficient
                 final double r = (1L << (2 * j)) - 1;

src/main/java/org/apache/commons/math4/analysis/integration/SimpsonIntegrator.java

@@ -105,7 +105,7 @@ public class SimpsonIntegrator extends BaseAbstractUnivariateIntegrator {
         double olds = (4 * oldt - s0) / 3.0;
         while (true) {
             // The first iteration is the first refinement of the sum.
-            iterations.incrementCount();
+            iterations.increment();
             final int i = getIterations();
             final double t = qtrap.stage(this, i + 1); // 1-stage ahead of the iteration
             final double s = (4 * t - oldt) / 3.0;

src/main/java/org/apache/commons/math4/analysis/integration/TrapezoidIntegrator.java

@@ -147,7 +147,7 @@ public class TrapezoidIntegrator extends BaseAbstractUnivariateIntegrator {
         throws MathIllegalArgumentException, TooManyEvaluationsException, MaxCountExceededException {
 
         double oldt = stage(this, 0);
-        iterations.incrementCount();
+        iterations.increment();
         while (true) {
             final int i = iterations.getCount();
             final double t = stage(this, i);
@@ -160,7 +160,7 @@ public class TrapezoidIntegrator extends BaseAbstractUnivariateIntegrator {
                 }
             }
             oldt = t;
-            iterations.incrementCount();
+            iterations.increment();
         }
 
     }

src/test/java/org/apache/commons/math4/analysis/integration/IterativeLegendreGaussIntegratorTest.java

@@ -117,7 +117,7 @@ public class IterativeLegendreGaussIntegratorTest {
 
         final double a = -5000;
         final double b = 5000;
-        final double s = integrator.integrate(50, normal, a, b);
+        final double s = integrator.integrate(60, normal, a, b);
         Assert.assertEquals(1, s, 1e-5);
     }