Hi, I noticed that you have code where fields and constructor arguments have the same name. As far as I remember that is not good practise, but I might be wrong :-)?
Cheers, Mikkel. 2011/1/30 <er...@apache.org>: > Author: erans > Date: Sat Jan 29 23:38:39 2011 > New Revision: 1065146 > > URL: http://svn.apache.org/viewvc?rev=1065146&view=rev > Log: > MATH-503 > Added sigmoid and generalized logistic functions. > > Added: > > commons/proper/math/trunk/src/main/java/org/apache/commons/math/analysis/function/Logistic.java > (with props) > > commons/proper/math/trunk/src/main/java/org/apache/commons/math/analysis/function/Sigmoid.java > (with props) > > commons/proper/math/trunk/src/test/java/org/apache/commons/math/analysis/function/ > > commons/proper/math/trunk/src/test/java/org/apache/commons/math/analysis/function/LogisticTest.java > (with props) > > commons/proper/math/trunk/src/test/java/org/apache/commons/math/analysis/function/SigmoidTest.java > (with props) > > Added: > commons/proper/math/trunk/src/main/java/org/apache/commons/math/analysis/function/Logistic.java > URL: > http://svn.apache.org/viewvc/commons/proper/math/trunk/src/main/java/org/apache/commons/math/analysis/function/Logistic.java?rev=1065146&view=auto > ============================================================================== > --- > commons/proper/math/trunk/src/main/java/org/apache/commons/math/analysis/function/Logistic.java > (added) > +++ > commons/proper/math/trunk/src/main/java/org/apache/commons/math/analysis/function/Logistic.java > Sat Jan 29 23:38:39 2011 > @@ -0,0 +1,78 @@ > +/* > + * Licensed to the Apache Software Foundation (ASF) under one or more > + * contributor license agreements. See the NOTICE file distributed with > + * this work for additional information regarding copyright ownership. > + * The ASF licenses this file to You under the Apache License, Version 2.0 > + * (the "License"); you may not use this file except in compliance with > + * the License. You may obtain a copy of the License at > + * > + * http://www.apache.org/licenses/LICENSE-2.0 > + * > + * Unless required by applicable law or agreed to in writing, software > + * distributed under the License is distributed on an "AS IS" BASIS, > + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. > + * See the License for the specific language governing permissions and > + * limitations under the License. > + */ > + > +package org.apache.commons.math.analysis.function; > + > +import org.apache.commons.math.analysis.UnivariateRealFunction; > +import org.apache.commons.math.exception.NotStrictlyPositiveException; > +import org.apache.commons.math.util.FastMath; > + > +/** > + * <a href="http://en.wikipedia.org/wiki/Generalised_logistic_function";> > + * Generalised logistic</a> function. > + * > + * @version $Revision$ $Date$ > + * @since 3.0 > + */ > +public class Logistic implements UnivariateRealFunction { > + /** Lower asymptote. */ > + private final double a; > + /** Upper asymptote. */ > + private final double k; > + /** Growth rate. */ > + private final double b; > + /** Parameter that affects near which asymptote maximum growth occurs. */ > + private final double n; > + /** Parameter that affects the position of the curve along the ordinate > axis. */ > + private final double q; > + /** Abscissa of maximum growth. */ > + private final double m; > + > + /** > + * @param k Upper asymptote. > + * @param m Abscissa of maximum growth. > + * @param b Growth rate. > + * @param q Parameter that affects the position of the curve along the > + * ordinate axis. > + * @param a Lower asymptote. > + * @param n Parameter that affects near which asymptote the maximum > + * growth occurs. > + * @throws NotStrictlyPositiveException if {@code n <= 0}. > + */ > + public Logistic(double k, > + double m, > + double b, > + double q, > + double a, > + double n) { > + if (n <= 0) { > + throw new NotStrictlyPositiveException(n); > + } > + > + this.k = k; > + this.m = m; > + this.b = b; > + this.q = q; > + this.a = a; > + this.n = n; > + } > + > + /** {@inheritDoc} */ > + public double value(double x) { > + return a + (k - a) / FastMath.pow((1 + q * FastMath.exp(b * (m - > x))), 1 / n); > + } > +} > > Propchange: > commons/proper/math/trunk/src/main/java/org/apache/commons/math/analysis/function/Logistic.java > ------------------------------------------------------------------------------ > svn:eol-style = native > > Added: > commons/proper/math/trunk/src/main/java/org/apache/commons/math/analysis/function/Sigmoid.java > URL: > http://svn.apache.org/viewvc/commons/proper/math/trunk/src/main/java/org/apache/commons/math/analysis/function/Sigmoid.java?rev=1065146&view=auto > ============================================================================== > --- > commons/proper/math/trunk/src/main/java/org/apache/commons/math/analysis/function/Sigmoid.java > (added) > +++ > commons/proper/math/trunk/src/main/java/org/apache/commons/math/analysis/function/Sigmoid.java > Sat Jan 29 23:38:39 2011 > @@ -0,0 +1,38 @@ > +/* > + * Licensed to the Apache Software Foundation (ASF) under one or more > + * contributor license agreements. See the NOTICE file distributed with > + * this work for additional information regarding copyright ownership. > + * The ASF licenses this file to You under the Apache License, Version 2.0 > + * (the "License"); you may not use this file except in compliance with > + * the License. You may obtain a copy of the License at > + * > + * http://www.apache.org/licenses/LICENSE-2.0 > + * > + * Unless required by applicable law or agreed to in writing, software > + * distributed under the License is distributed on an "AS IS" BASIS, > + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. > + * See the License for the specific language governing permissions and > + * limitations under the License. > + */ > + > +package org.apache.commons.math.analysis.function; > + > +import org.apache.commons.math.analysis.UnivariateRealFunction; > +import org.apache.commons.math.exception.NotStrictlyPositiveException; > +import org.apache.commons.math.util.FastMath; > + > +/** > + * <a href="http://en.wikipedia.org/wiki/Sigmoid_function";> > + * Sigmoid</a> function. > + * A more flexible version, the generalised logistic, is implemented > + * by the {@link Logistic} class. > + * > + * @version $Revision$ $Date$ > + * @since 3.0 > + */ > +public class Sigmoid implements UnivariateRealFunction { > + /** {@inheritDoc} */ > + public double value(double x) { > + return 1 / (1 + FastMath.exp(-x)); > + } > +} > > Propchange: > commons/proper/math/trunk/src/main/java/org/apache/commons/math/analysis/function/Sigmoid.java > ------------------------------------------------------------------------------ > svn:eol-style = native > > Added: > commons/proper/math/trunk/src/test/java/org/apache/commons/math/analysis/function/LogisticTest.java > URL: > http://svn.apache.org/viewvc/commons/proper/math/trunk/src/test/java/org/apache/commons/math/analysis/function/LogisticTest.java?rev=1065146&view=auto > ============================================================================== > --- > commons/proper/math/trunk/src/test/java/org/apache/commons/math/analysis/function/LogisticTest.java > (added) > +++ > commons/proper/math/trunk/src/test/java/org/apache/commons/math/analysis/function/LogisticTest.java > Sat Jan 29 23:38:39 2011 > @@ -0,0 +1,84 @@ > +/* > + * Licensed to the Apache Software Foundation (ASF) under one or more > + * contributor license agreements. See the NOTICE file distributed with > + * this work for additional information regarding copyright ownership. > + * The ASF licenses this file to You under the Apache License, Version 2.0 > + * (the "License"); you may not use this file except in compliance with > + * the License. You may obtain a copy of the License at > + * > + * http://www.apache.org/licenses/LICENSE-2.0 > + * > + * Unless required by applicable law or agreed to in writing, software > + * distributed under the License is distributed on an "AS IS" BASIS, > + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. > + * See the License for the specific language governing permissions and > + * limitations under the License. > + */ > + > +package org.apache.commons.math.analysis.function; > + > +import org.apache.commons.math.analysis.UnivariateRealFunction; > +import org.apache.commons.math.exception.NotStrictlyPositiveException; > +import org.apache.commons.math.util.FastMath; > + > +import org.junit.Assert; > +import org.junit.Test; > + > +/** > + * Test for class {@link Logistic}. > + */ > +public class LogisticTest { > + private final double EPS = Math.ulp(1d); > + > + @Test > + public void testPreconditions() { > + try { > + final UnivariateRealFunction f = new Logistic(1, 0, 1, 1, 0, -1); > + } catch (NotStrictlyPositiveException e) { > + // Expected. > + } > + > + try { > + final UnivariateRealFunction f = new Logistic(1, 0, 1, 1, 0, 0); > + } catch (NotStrictlyPositiveException e) { > + // Expected. > + } > + } > + > + @Test > + public void testCompareSigmoid() { > + final UnivariateRealFunction sig = new Sigmoid(); > + final UnivariateRealFunction sigL = new Logistic(1, 0, 1, 1, 0, 1); > + > + final double min = -2; > + final double max = 2; > + final int n = 100; > + final double delta = (max - min) / n; > + for (int i = 0; i < n; i++) { > + final double x = min + i * delta; > + Assert.assertEquals("x=" + x, sig.value(x), sigL.value(x), EPS); > + } > + } > + > + @Test > + public void testSomeValues() { > + final double k = 4; > + final double m = 5; > + final double b = 2; > + final double q = 3; > + final double a = -1; > + final double n = 2; > + > + final UnivariateRealFunction f = new Logistic(k, m, b, q, a, n); > + > + double x; > + x = m; > + Assert.assertEquals("x=" + x, a + (k - a) / FastMath.sqrt(1 + q), > f.value(x), EPS); > + > + x = Double.NEGATIVE_INFINITY; > + Assert.assertEquals("x=" + x, a, f.value(x), EPS); > + > + x = Double.POSITIVE_INFINITY; > + Assert.assertEquals("x=" + x, k, f.value(x), EPS); > + } > +} > > Propchange: > commons/proper/math/trunk/src/test/java/org/apache/commons/math/analysis/function/LogisticTest.java > ------------------------------------------------------------------------------ > svn:eol-style = native > > Added: > commons/proper/math/trunk/src/test/java/org/apache/commons/math/analysis/function/SigmoidTest.java > URL: > http://svn.apache.org/viewvc/commons/proper/math/trunk/src/test/java/org/apache/commons/math/analysis/function/SigmoidTest.java?rev=1065146&view=auto > ============================================================================== > --- > commons/proper/math/trunk/src/test/java/org/apache/commons/math/analysis/function/SigmoidTest.java > (added) > +++ > commons/proper/math/trunk/src/test/java/org/apache/commons/math/analysis/function/SigmoidTest.java > Sat Jan 29 23:38:39 2011 > @@ -0,0 +1,47 @@ > +/* > + * Licensed to the Apache Software Foundation (ASF) under one or more > + * contributor license agreements. See the NOTICE file distributed with > + * this work for additional information regarding copyright ownership. > + * The ASF licenses this file to You under the Apache License, Version 2.0 > + * (the "License"); you may not use this file except in compliance with > + * the License. You may obtain a copy of the License at > + * > + * http://www.apache.org/licenses/LICENSE-2.0 > + * > + * Unless required by applicable law or agreed to in writing, software > + * distributed under the License is distributed on an "AS IS" BASIS, > + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. > + * See the License for the specific language governing permissions and > + * limitations under the License. > + */ > + > +package org.apache.commons.math.analysis.function; > + > +import org.apache.commons.math.analysis.UnivariateRealFunction; > +import org.apache.commons.math.exception.NotStrictlyPositiveException; > +import org.apache.commons.math.util.FastMath; > + > +import org.junit.Assert; > +import org.junit.Test; > + > +/** > + * Test for class {@link Sigmoid}. > + */ > +public class SigmoidTest { > + private final double EPS = Math.ulp(1d); > + > + @Test > + public void testSomeValues() { > + final UnivariateRealFunction f = new Sigmoid(); > + > + double x; > + x = 0; > + Assert.assertEquals("x=" + x, 0.5, f.value(x), EPS); > + > + x = Double.NEGATIVE_INFINITY; > + Assert.assertEquals("x=" + x, 0, f.value(x), EPS); > + > + x = Double.POSITIVE_INFINITY; > + Assert.assertEquals("x=" + x, 1, f.value(x), EPS); > + } > +} > > Propchange: > commons/proper/math/trunk/src/test/java/org/apache/commons/math/analysis/function/SigmoidTest.java > ------------------------------------------------------------------------------ > svn:eol-style = native > > > --------------------------------------------------------------------- To unsubscribe, e-mail: dev-unsubscr...@commons.apache.org For additional commands, e-mail: dev-h...@commons.apache.org
