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test/java/lang/Math/Log1pTests.java

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   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  */
  23 
  24 /*
  25  * @test
  26  * @bug 4851638 4939441
  27  * @summary Tests for {Math, StrictMath}.log1p
  28  * @author Joseph D. Darcy

  29  */
  30 
  31 public class Log1pTests {
  32     private Log1pTests(){}
  33 
  34     static final double infinityD = Double.POSITIVE_INFINITY;
  35     static final double NaNd = Double.NaN;
  36 
  37     /**
  38      * Formulation taken from HP-15C Advanced Functions Handbook, part
  39      * number HP 0015-90011, p 181.  This is accurate to a few ulps.
  40      */
  41     static double hp15cLogp(double x) {
  42         double u = 1.0 + x;
  43         return (u==1.0? x : StrictMath.log(u)*x/(u-1) );
  44     }
  45 
  46     /*
  47      * The Taylor expansion of ln(1 + x) for -1 < x <= 1 is:
  48      *




   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  */
  23 
  24 /*
  25  * @test
  26  * @bug 4851638 4939441
  27  * @summary Tests for {Math, StrictMath}.log1p
  28  * @author Joseph D. Darcy
  29  * @key randomness
  30  */
  31 
  32 public class Log1pTests {
  33     private Log1pTests(){}
  34 
  35     static final double infinityD = Double.POSITIVE_INFINITY;
  36     static final double NaNd = Double.NaN;
  37 
  38     /**
  39      * Formulation taken from HP-15C Advanced Functions Handbook, part
  40      * number HP 0015-90011, p 181.  This is accurate to a few ulps.
  41      */
  42     static double hp15cLogp(double x) {
  43         double u = 1.0 + x;
  44         return (u==1.0? x : StrictMath.log(u)*x/(u-1) );
  45     }
  46 
  47     /*
  48      * The Taylor expansion of ln(1 + x) for -1 < x <= 1 is:
  49      *


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