<p>There is a <a href="http://arxiv.org/abs/0908.3030v3" rel="noreferrer">Math.BigDecimal implementation of core mathematical functions</a> with source code available from the Cornell University Library <a href="http://arxiv.org/src/0908.3030v3/anc" rel="noreferrer">here</a> (also you can download the library as a <a href="http://arxiv.org/src/0908.3030v3" rel="noreferrer">tar.gz</a>). Here is a sample of the library use:</p>

<pre><code>import org.nevec.rjm.*;
import java.math.BigDecimal;

public class test {
    public static void main(String... args) {
        BigDecimal a = new BigDecimal("1.21");
        BigDecimal b = new BigDecimal("0.5");

        System.out.println(BigDecimalMath.pow(a, b).toString());
    }
}
</code></pre>

<p>Prints out: </p>

<pre><code>1.1
</code></pre>

<hr>

<h1>Update</h1>

<p>The license information is now clear in the May 2015 update:</p>

<blockquote>
  <p>The full source code is made available under the LGPL v3.0.</p>
</blockquote>
Java's BigDecimal.power(BigDecimal exponent): Is there a Java library that does it?
<p>Java's <code>BigDecimal.pow(int)</code> method only accepts an integer parameter, no <code>BigDecimal</code> parameter. </p>

<p>Is there a library, like Apache's commons-lang, that supports <code>BigDecimal.pow(BigDecimal)</code>? It should be able to do calculate <code>"1.21".pow("0.5")</code> to return <code>"1.1"</code>.</p>