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Posted to commits@commons.apache.org by ce...@apache.org on 2012/01/04 04:47:46 UTC
svn commit: r1227042 - in /commons/proper/math/trunk/src:
main/java/org/apache/commons/math/transform/
main/java/org/apache/commons/math/util/
test/java/org/apache/commons/math/util/
Author: celestin
Date: Wed Jan 4 03:47:46 2012
New Revision: 1227042
URL: http://svn.apache.org/viewvc?rev=1227042&view=rev
Log:
Moved o.a.c.m.transform.FastFourierTransformer.isPowerOf2 to o.a.c.m.util.ArithmeticUtils.isPowerOfTwo (MATH-677).
Modified:
commons/proper/math/trunk/src/main/java/org/apache/commons/math/transform/FastCosineTransformer.java
commons/proper/math/trunk/src/main/java/org/apache/commons/math/transform/FastFourierTransformer.java
commons/proper/math/trunk/src/main/java/org/apache/commons/math/transform/FastHadamardTransformer.java
commons/proper/math/trunk/src/main/java/org/apache/commons/math/util/ArithmeticUtils.java
commons/proper/math/trunk/src/test/java/org/apache/commons/math/util/ArithmeticUtilsTest.java
Modified: commons/proper/math/trunk/src/main/java/org/apache/commons/math/transform/FastCosineTransformer.java
URL: http://svn.apache.org/viewvc/commons/proper/math/trunk/src/main/java/org/apache/commons/math/transform/FastCosineTransformer.java?rev=1227042&r1=1227041&r2=1227042&view=diff
==============================================================================
--- commons/proper/math/trunk/src/main/java/org/apache/commons/math/transform/FastCosineTransformer.java (original)
+++ commons/proper/math/trunk/src/main/java/org/apache/commons/math/transform/FastCosineTransformer.java Wed Jan 4 03:47:46 2012
@@ -22,6 +22,7 @@ import org.apache.commons.math.exception
import org.apache.commons.math.exception.NonMonotonicSequenceException;
import org.apache.commons.math.exception.NotStrictlyPositiveException;
import org.apache.commons.math.exception.util.LocalizedFormats;
+import org.apache.commons.math.util.ArithmeticUtils;
import org.apache.commons.math.util.FastMath;
/**
@@ -238,7 +239,7 @@ public class FastCosineTransformer imple
final double[] transformed = new double[f.length];
final int n = f.length - 1;
- if (!FastFourierTransformer.isPowerOf2(n)) {
+ if (!ArithmeticUtils.isPowerOfTwo(n)) {
throw new MathIllegalArgumentException(
LocalizedFormats.NOT_POWER_OF_TWO_PLUS_ONE,
Integer.valueOf(f.length));
Modified: commons/proper/math/trunk/src/main/java/org/apache/commons/math/transform/FastFourierTransformer.java
URL: http://svn.apache.org/viewvc/commons/proper/math/trunk/src/main/java/org/apache/commons/math/transform/FastFourierTransformer.java?rev=1227042&r1=1227041&r2=1227042&view=diff
==============================================================================
--- commons/proper/math/trunk/src/main/java/org/apache/commons/math/transform/FastFourierTransformer.java (original)
+++ commons/proper/math/trunk/src/main/java/org/apache/commons/math/transform/FastFourierTransformer.java Wed Jan 4 03:47:46 2012
@@ -29,6 +29,7 @@ import org.apache.commons.math.exception
import org.apache.commons.math.exception.OutOfRangeException;
import org.apache.commons.math.exception.ZeroException;
import org.apache.commons.math.exception.util.LocalizedFormats;
+import org.apache.commons.math.util.ArithmeticUtils;
import org.apache.commons.math.util.FastMath;
/**
@@ -466,16 +467,6 @@ public class FastFourierTransformer impl
}
/**
- * Returns true if the argument is a power of 2.
- *
- * @param n the number to test
- * @return true if the argument is a power of 2
- */
- public static boolean isPowerOf2(long n) {
- return (n > 0) && ((n & (n - 1)) == 0);
- }
-
- /**
* Verifies that the data set has length of power of 2.
*
* @param d the data array
@@ -484,7 +475,7 @@ public class FastFourierTransformer impl
public static void verifyDataSet(double[] d)
throws MathIllegalArgumentException {
- if (!isPowerOf2(d.length)) {
+ if (!ArithmeticUtils.isPowerOfTwo(d.length)) {
throw new MathIllegalArgumentException(
LocalizedFormats.NOT_POWER_OF_TWO_CONSIDER_PADDING,
Integer.valueOf(d.length));
@@ -500,7 +491,7 @@ public class FastFourierTransformer impl
public static void verifyDataSet(Object[] o)
throws MathIllegalArgumentException {
- if (!isPowerOf2(o.length)) {
+ if (!ArithmeticUtils.isPowerOfTwo(o.length)) {
throw new MathIllegalArgumentException(
LocalizedFormats.NOT_POWER_OF_TWO_CONSIDER_PADDING,
Integer.valueOf(o.length));
Modified: commons/proper/math/trunk/src/main/java/org/apache/commons/math/transform/FastHadamardTransformer.java
URL: http://svn.apache.org/viewvc/commons/proper/math/trunk/src/main/java/org/apache/commons/math/transform/FastHadamardTransformer.java?rev=1227042&r1=1227041&r2=1227042&view=diff
==============================================================================
--- commons/proper/math/trunk/src/main/java/org/apache/commons/math/transform/FastHadamardTransformer.java (original)
+++ commons/proper/math/trunk/src/main/java/org/apache/commons/math/transform/FastHadamardTransformer.java Wed Jan 4 03:47:46 2012
@@ -21,6 +21,7 @@ import org.apache.commons.math.exception
import org.apache.commons.math.exception.NonMonotonicSequenceException;
import org.apache.commons.math.exception.NotStrictlyPositiveException;
import org.apache.commons.math.exception.util.LocalizedFormats;
+import org.apache.commons.math.util.ArithmeticUtils;
/**
* Implements the <a href="http://www.archive.chipcenter.com/dsp/DSP000517F1.html">Fast Hadamard Transform</a> (FHT).
@@ -259,7 +260,7 @@ public class FastHadamardTransformer imp
final int n = x.length;
final int halfN = n / 2;
- if (!FastFourierTransformer.isPowerOf2(n)) {
+ if (!ArithmeticUtils.isPowerOfTwo(n)) {
throw new MathIllegalArgumentException(
LocalizedFormats.NOT_POWER_OF_TWO,
Integer.valueOf(n));
@@ -311,7 +312,7 @@ public class FastHadamardTransformer imp
final int n = x.length;
final int halfN = n / 2;
- if (!FastFourierTransformer.isPowerOf2(n)) {
+ if (!ArithmeticUtils.isPowerOfTwo(n)) {
throw new MathIllegalArgumentException(
LocalizedFormats.NOT_POWER_OF_TWO,
Integer.valueOf(n));
Modified: commons/proper/math/trunk/src/main/java/org/apache/commons/math/util/ArithmeticUtils.java
URL: http://svn.apache.org/viewvc/commons/proper/math/trunk/src/main/java/org/apache/commons/math/util/ArithmeticUtils.java?rev=1227042&r1=1227041&r2=1227042&view=diff
==============================================================================
--- commons/proper/math/trunk/src/main/java/org/apache/commons/math/util/ArithmeticUtils.java (original)
+++ commons/proper/math/trunk/src/main/java/org/apache/commons/math/util/ArithmeticUtils.java Wed Jan 4 03:47:46 2012
@@ -18,7 +18,6 @@ package org.apache.commons.math.util;
import java.math.BigInteger;
import org.apache.commons.math.exception.MathArithmeticException;
-import org.apache.commons.math.exception.MathIllegalNumberException;
import org.apache.commons.math.exception.NotPositiveException;
import org.apache.commons.math.exception.NumberIsTooLargeException;
import org.apache.commons.math.exception.util.Localizable;
@@ -943,4 +942,14 @@ public final class ArithmeticUtils {
throw new NotPositiveException(LocalizedFormats.BINOMIAL_NEGATIVE_PARAMETER, n);
}
}
+
+ /**
+ * Returns true if the argument is a power of two.
+ *
+ * @param n the number to test
+ * @return true if the argument is a power of two
+ */
+ public static boolean isPowerOfTwo(long n) {
+ return (n > 0) && ((n & (n - 1)) == 0);
+ }
}
Modified: commons/proper/math/trunk/src/test/java/org/apache/commons/math/util/ArithmeticUtilsTest.java
URL: http://svn.apache.org/viewvc/commons/proper/math/trunk/src/test/java/org/apache/commons/math/util/ArithmeticUtilsTest.java?rev=1227042&r1=1227041&r2=1227042&view=diff
==============================================================================
--- commons/proper/math/trunk/src/test/java/org/apache/commons/math/util/ArithmeticUtilsTest.java (original)
+++ commons/proper/math/trunk/src/test/java/org/apache/commons/math/util/ArithmeticUtilsTest.java Wed Jan 4 03:47:46 2012
@@ -17,6 +17,7 @@
package org.apache.commons.math.util;
import java.util.ArrayList;
+import java.util.Arrays;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
@@ -678,6 +679,20 @@ public class ArithmeticUtilsTest {
}
+ @Test
+ public void testIsPowerOfTwo() {
+ final int n = 1025;
+ final boolean[] expected = new boolean[n];
+ Arrays.fill(expected, false);
+ for (int i = 1; i < expected.length; i *= 2) {
+ expected[i] = true;
+ }
+ for (int i = 0; i < expected.length; i++) {
+ final boolean actual = ArithmeticUtils.isPowerOfTwo(i);
+ Assert.assertTrue(Integer.toString(i), actual == expected[i]);
+ }
+ }
+
/**
* Exact (caching) recursive implementation to test against
*/
@@ -750,6 +765,5 @@ public class ArithmeticUtilsTest {
} catch (MathArithmeticException ex) {
// success
}
-
}
}