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<HTML> <BODY BGCOLOR="white"> <PRE> <FONT color="green">001</FONT> /*<a name="line.1"></a> <FONT color="green">002</FONT> * Licensed to the Apache Software Foundation (ASF) under one or more<a name="line.2"></a> <FONT color="green">003</FONT> * contributor license agreements. See the NOTICE file distributed with<a name="line.3"></a> <FONT color="green">004</FONT> * this work for additional information regarding copyright ownership.<a name="line.4"></a> <FONT color="green">005</FONT> * The ASF licenses this file to You under the Apache License, Version 2.0<a name="line.5"></a> <FONT color="green">006</FONT> * (the "License"); you may not use this file except in compliance with<a name="line.6"></a> <FONT color="green">007</FONT> * the License. You may obtain a copy of the License at<a name="line.7"></a> <FONT color="green">008</FONT> *<a name="line.8"></a> <FONT color="green">009</FONT> * http://www.apache.org/licenses/LICENSE-2.0<a name="line.9"></a> <FONT color="green">010</FONT> *<a name="line.10"></a> <FONT color="green">011</FONT> * Unless required by applicable law or agreed to in writing, software<a name="line.11"></a> <FONT color="green">012</FONT> * distributed under the License is distributed on an "AS IS" BASIS,<a name="line.12"></a> <FONT color="green">013</FONT> * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.<a name="line.13"></a> <FONT color="green">014</FONT> * See the License for the specific language governing permissions and<a name="line.14"></a> <FONT color="green">015</FONT> * limitations under the License.<a name="line.15"></a> <FONT color="green">016</FONT> */<a name="line.16"></a> <FONT color="green">017</FONT> package org.apache.commons.math.stat.descriptive.rank;<a name="line.17"></a> <FONT color="green">018</FONT> <a name="line.18"></a> <FONT color="green">019</FONT> import java.io.Serializable;<a name="line.19"></a> <FONT color="green">020</FONT> import java.util.Arrays;<a name="line.20"></a> <FONT color="green">021</FONT> <a name="line.21"></a> <FONT color="green">022</FONT> import org.apache.commons.math.MathRuntimeException;<a name="line.22"></a> <FONT color="green">023</FONT> import org.apache.commons.math.stat.descriptive.AbstractUnivariateStatistic;<a name="line.23"></a> <FONT color="green">024</FONT> <a name="line.24"></a> <FONT color="green">025</FONT> /**<a name="line.25"></a> <FONT color="green">026</FONT> * Provides percentile computation.<a name="line.26"></a> <FONT color="green">027</FONT> * <p><a name="line.27"></a> <FONT color="green">028</FONT> * There are several commonly used methods for estimating percentiles (a.k.a.<a name="line.28"></a> <FONT color="green">029</FONT> * quantiles) based on sample data. For large samples, the different methods<a name="line.29"></a> <FONT color="green">030</FONT> * agree closely, but when sample sizes are small, different methods will give<a name="line.30"></a> <FONT color="green">031</FONT> * significantly different results. The algorithm implemented here works as follows:<a name="line.31"></a> <FONT color="green">032</FONT> * <ol><a name="line.32"></a> <FONT color="green">033</FONT> * <li>Let <code>n</code> be the length of the (sorted) array and<a name="line.33"></a> <FONT color="green">034</FONT> * <code>0 < p <= 100</code> be the desired percentile.</li><a name="line.34"></a> <FONT color="green">035</FONT> * <li>If <code> n = 1 </code> return the unique array element (regardless of<a name="line.35"></a> <FONT color="green">036</FONT> * the value of <code>p</code>); otherwise </li><a name="line.36"></a> <FONT color="green">037</FONT> * <li>Compute the estimated percentile position<a name="line.37"></a> <FONT color="green">038</FONT> * <code> pos = p * (n + 1) / 100</code> and the difference, <code>d</code><a name="line.38"></a> <FONT color="green">039</FONT> * between <code>pos</code> and <code>floor(pos)</code> (i.e. the fractional<a name="line.39"></a> <FONT color="green">040</FONT> * part of <code>pos</code>). If <code>pos >= n</code> return the largest<a name="line.40"></a> <FONT color="green">041</FONT> * element in the array; otherwise</li><a name="line.41"></a> <FONT color="green">042</FONT> * <li>Let <code>lower</code> be the element in position<a name="line.42"></a> <FONT color="green">043</FONT> * <code>floor(pos)</code> in the array and let <code>upper</code> be the<a name="line.43"></a> <FONT color="green">044</FONT> * next element in the array. Return <code>lower + d * (upper - lower)</code><a name="line.44"></a> <FONT color="green">045</FONT> * </li><a name="line.45"></a> <FONT color="green">046</FONT> * </ol></p><a name="line.46"></a> <FONT color="green">047</FONT> * <p><a name="line.47"></a> <FONT color="green">048</FONT> * To compute percentiles, the data must be (totally) ordered. Input arrays<a name="line.48"></a> <FONT color="green">049</FONT> * are copied and then sorted using {@link java.util.Arrays#sort(double[])}.<a name="line.49"></a> <FONT color="green">050</FONT> * The ordering used by <code>Arrays.sort(double[])</code> is the one determined<a name="line.50"></a> <FONT color="green">051</FONT> * by {@link java.lang.Double#compareTo(Double)}. This ordering makes<a name="line.51"></a> <FONT color="green">052</FONT> * <code>Double.NaN</code> larger than any other value (including<a name="line.52"></a> <FONT color="green">053</FONT> * <code>Double.POSITIVE_INFINITY</code>). Therefore, for example, the median<a name="line.53"></a> <FONT color="green">054</FONT> * (50th percentile) of<a name="line.54"></a> <FONT color="green">055</FONT> * <code>{0, 1, 2, 3, 4, Double.NaN}</code> evaluates to <code>2.5.</code></p><a name="line.55"></a> <FONT color="green">056</FONT> * <p><a name="line.56"></a> <FONT color="green">057</FONT> * Since percentile estimation usually involves interpolation between array<a name="line.57"></a> <FONT color="green">058</FONT> * elements, arrays containing <code>NaN</code> or infinite values will often<a name="line.58"></a> <FONT color="green">059</FONT> * result in <code>NaN<code> or infinite values returned.</p><a name="line.59"></a> <FONT color="green">060</FONT> * <p><a name="line.60"></a> <FONT color="green">061</FONT> * <strong>Note that this implementation is not synchronized.</strong> If<a name="line.61"></a> <FONT color="green">062</FONT> * multiple threads access an instance of this class concurrently, and at least<a name="line.62"></a> <FONT color="green">063</FONT> * one of the threads invokes the <code>increment()</code> or<a name="line.63"></a> <FONT color="green">064</FONT> * <code>clear()</code> method, it must be synchronized externally.</p><a name="line.64"></a> <FONT color="green">065</FONT> *<a name="line.65"></a> <FONT color="green">066</FONT> * @version $Revision: 811685 $ $Date: 2009-09-05 13:36:48 -0400 (Sat, 05 Sep 2009) $<a name="line.66"></a> <FONT color="green">067</FONT> */<a name="line.67"></a> <FONT color="green">068</FONT> public class Percentile extends AbstractUnivariateStatistic implements Serializable {<a name="line.68"></a> <FONT color="green">069</FONT> <a name="line.69"></a> <FONT color="green">070</FONT> /** Serializable version identifier */<a name="line.70"></a> <FONT color="green">071</FONT> private static final long serialVersionUID = -8091216485095130416L;<a name="line.71"></a> <FONT color="green">072</FONT> <a name="line.72"></a> <FONT color="green">073</FONT> /** Determines what percentile is computed when evaluate() is activated<a name="line.73"></a> <FONT color="green">074</FONT> * with no quantile argument */<a name="line.74"></a> <FONT color="green">075</FONT> private double quantile = 0.0;<a name="line.75"></a> <FONT color="green">076</FONT> <a name="line.76"></a> <FONT color="green">077</FONT> /**<a name="line.77"></a> <FONT color="green">078</FONT> * Constructs a Percentile with a default quantile<a name="line.78"></a> <FONT color="green">079</FONT> * value of 50.0.<a name="line.79"></a> <FONT color="green">080</FONT> */<a name="line.80"></a> <FONT color="green">081</FONT> public Percentile() {<a name="line.81"></a> <FONT color="green">082</FONT> this(50.0);<a name="line.82"></a> <FONT color="green">083</FONT> }<a name="line.83"></a> <FONT color="green">084</FONT> <a name="line.84"></a> <FONT color="green">085</FONT> /**<a name="line.85"></a> <FONT color="green">086</FONT> * Constructs a Percentile with the specific quantile value.<a name="line.86"></a> <FONT color="green">087</FONT> * @param p the quantile<a name="line.87"></a> <FONT color="green">088</FONT> * @throws IllegalArgumentException if p is not greater than 0 and less<a name="line.88"></a> <FONT color="green">089</FONT> * than or equal to 100<a name="line.89"></a> <FONT color="green">090</FONT> */<a name="line.90"></a> <FONT color="green">091</FONT> public Percentile(final double p) {<a name="line.91"></a> <FONT color="green">092</FONT> setQuantile(p);<a name="line.92"></a> <FONT color="green">093</FONT> }<a name="line.93"></a> <FONT color="green">094</FONT> <a name="line.94"></a> <FONT color="green">095</FONT> /**<a name="line.95"></a> <FONT color="green">096</FONT> * Copy constructor, creates a new {@code Percentile} identical<a name="line.96"></a> <FONT color="green">097</FONT> * to the {@code original}<a name="line.97"></a> <FONT color="green">098</FONT> *<a name="line.98"></a> <FONT color="green">099</FONT> * @param original the {@code Percentile} instance to copy<a name="line.99"></a> <FONT color="green">100</FONT> */<a name="line.100"></a> <FONT color="green">101</FONT> public Percentile(Percentile original) {<a name="line.101"></a> <FONT color="green">102</FONT> copy(original, this);<a name="line.102"></a> <FONT color="green">103</FONT> }<a name="line.103"></a> <FONT color="green">104</FONT> <a name="line.104"></a> <FONT color="green">105</FONT> /**<a name="line.105"></a> <FONT color="green">106</FONT> * Returns an estimate of the <code>p</code>th percentile of the values<a name="line.106"></a> <FONT color="green">107</FONT> * in the <code>values</code> array.<a name="line.107"></a> <FONT color="green">108</FONT> * <p><a name="line.108"></a> <FONT color="green">109</FONT> * Calls to this method do not modify the internal <code>quantile</code><a name="line.109"></a> <FONT color="green">110</FONT> * state of this statistic.</p><a name="line.110"></a> <FONT color="green">111</FONT> * <p><a name="line.111"></a> <FONT color="green">112</FONT> * <ul><a name="line.112"></a> <FONT color="green">113</FONT> * <li>Returns <code>Double.NaN</code> if <code>values</code> has length<a name="line.113"></a> <FONT color="green">114</FONT> * <code>0</code></li><a name="line.114"></a> <FONT color="green">115</FONT> * <li>Returns (for any value of <code>p</code>) <code>values[0]</code><a name="line.115"></a> <FONT color="green">116</FONT> * if <code>values</code> has length <code>1</code></li><a name="line.116"></a> <FONT color="green">117</FONT> * <li>Throws <code>IllegalArgumentException</code> if <code>values</code><a name="line.117"></a> <FONT color="green">118</FONT> * is null or p is not a valid quantile value (p must be greater than 0<a name="line.118"></a> <FONT color="green">119</FONT> * and less than or equal to 100) </li><a name="line.119"></a> <FONT color="green">120</FONT> * </ul></p><a name="line.120"></a> <FONT color="green">121</FONT> * <p><a name="line.121"></a> <FONT color="green">122</FONT> * See {@link Percentile} for a description of the percentile estimation<a name="line.122"></a> <FONT color="green">123</FONT> * algorithm used.</p><a name="line.123"></a> <FONT color="green">124</FONT> *<a name="line.124"></a> <FONT color="green">125</FONT> * @param values input array of values<a name="line.125"></a> <FONT color="green">126</FONT> * @param p the percentile value to compute<a name="line.126"></a> <FONT color="green">127</FONT> * @return the percentile value or Double.NaN if the array is empty<a name="line.127"></a> <FONT color="green">128</FONT> * @throws IllegalArgumentException if <code>values</code> is null<a name="line.128"></a> <FONT color="green">129</FONT> * or p is invalid<a name="line.129"></a> <FONT color="green">130</FONT> */<a name="line.130"></a> <FONT color="green">131</FONT> public double evaluate(final double[] values, final double p) {<a name="line.131"></a> <FONT color="green">132</FONT> test(values, 0, 0);<a name="line.132"></a> <FONT color="green">133</FONT> return evaluate(values, 0, values.length, p);<a name="line.133"></a> <FONT color="green">134</FONT> }<a name="line.134"></a> <FONT color="green">135</FONT> <a name="line.135"></a> <FONT color="green">136</FONT> /**<a name="line.136"></a> <FONT color="green">137</FONT> * Returns an estimate of the <code>quantile</code>th percentile of the<a name="line.137"></a> <FONT color="green">138</FONT> * designated values in the <code>values</code> array. The quantile<a name="line.138"></a> <FONT color="green">139</FONT> * estimated is determined by the <code>quantile</code> property.<a name="line.139"></a> <FONT color="green">140</FONT> * <p><a name="line.140"></a> <FONT color="green">141</FONT> * <ul><a name="line.141"></a> <FONT color="green">142</FONT> * <li>Returns <code>Double.NaN</code> if <code>length = 0</code></li><a name="line.142"></a> <FONT color="green">143</FONT> * <li>Returns (for any value of <code>quantile</code>)<a name="line.143"></a> <FONT color="green">144</FONT> * <code>values[begin]</code> if <code>length = 1 </code></li><a name="line.144"></a> <FONT color="green">145</FONT> * <li>Throws <code>IllegalArgumentException</code> if <code>values</code><a name="line.145"></a> <FONT color="green">146</FONT> * is null, or <code>start</code> or <code>length</code><a name="line.146"></a> <FONT color="green">147</FONT> * is invalid</li><a name="line.147"></a> <FONT color="green">148</FONT> * </ul></p><a name="line.148"></a> <FONT color="green">149</FONT> * <p><a name="line.149"></a> <FONT color="green">150</FONT> * See {@link Percentile} for a description of the percentile estimation<a name="line.150"></a> <FONT color="green">151</FONT> * algorithm used.</p><a name="line.151"></a> <FONT color="green">152</FONT> *<a name="line.152"></a> <FONT color="green">153</FONT> * @param values the input array<a name="line.153"></a> <FONT color="green">154</FONT> * @param start index of the first array element to include<a name="line.154"></a> <FONT color="green">155</FONT> * @param length the number of elements to include<a name="line.155"></a> <FONT color="green">156</FONT> * @return the percentile value<a name="line.156"></a> <FONT color="green">157</FONT> * @throws IllegalArgumentException if the parameters are not valid<a name="line.157"></a> <FONT color="green">158</FONT> *<a name="line.158"></a> <FONT color="green">159</FONT> */<a name="line.159"></a> <FONT color="green">160</FONT> @Override<a name="line.160"></a> <FONT color="green">161</FONT> public double evaluate( final double[] values, final int start, final int length) {<a name="line.161"></a> <FONT color="green">162</FONT> return evaluate(values, start, length, quantile);<a name="line.162"></a> <FONT color="green">163</FONT> }<a name="line.163"></a> <FONT color="green">164</FONT> <a name="line.164"></a> <FONT color="green">165</FONT> /**<a name="line.165"></a> <FONT color="green">166</FONT> * Returns an estimate of the <code>p</code>th percentile of the values<a name="line.166"></a> <FONT color="green">167</FONT> * in the <code>values</code> array, starting with the element in (0-based)<a name="line.167"></a> <FONT color="green">168</FONT> * position <code>begin</code> in the array and including <code>length</code><a name="line.168"></a> <FONT color="green">169</FONT> * values.<a name="line.169"></a> <FONT color="green">170</FONT> * <p><a name="line.170"></a> <FONT color="green">171</FONT> * Calls to this method do not modify the internal <code>quantile</code><a name="line.171"></a> <FONT color="green">172</FONT> * state of this statistic.</p><a name="line.172"></a> <FONT color="green">173</FONT> * <p><a name="line.173"></a> <FONT color="green">174</FONT> * <ul><a name="line.174"></a> <FONT color="green">175</FONT> * <li>Returns <code>Double.NaN</code> if <code>length = 0</code></li><a name="line.175"></a> <FONT color="green">176</FONT> * <li>Returns (for any value of <code>p</code>) <code>values[begin]</code><a name="line.176"></a> <FONT color="green">177</FONT> * if <code>length = 1 </code></li><a name="line.177"></a> <FONT color="green">178</FONT> * <li>Throws <code>IllegalArgumentException</code> if <code>values</code><a name="line.178"></a> <FONT color="green">179</FONT> * is null , <code>begin</code> or <code>length</code> is invalid, or<a name="line.179"></a> <FONT color="green">180</FONT> * <code>p</code> is not a valid quantile value (p must be greater than 0<a name="line.180"></a> <FONT color="green">181</FONT> * and less than or equal to 100)</li><a name="line.181"></a> <FONT color="green">182</FONT> * </ul></p><a name="line.182"></a> <FONT color="green">183</FONT> * <p><a name="line.183"></a> <FONT color="green">184</FONT> * See {@link Percentile} for a description of the percentile estimation<a name="line.184"></a> <FONT color="green">185</FONT> * algorithm used.</p><a name="line.185"></a> <FONT color="green">186</FONT> *<a name="line.186"></a> <FONT color="green">187</FONT> * @param values array of input values<a name="line.187"></a> <FONT color="green">188</FONT> * @param p the percentile to compute<a name="line.188"></a> <FONT color="green">189</FONT> * @param begin the first (0-based) element to include in the computation<a name="line.189"></a> <FONT color="green">190</FONT> * @param length the number of array elements to include<a name="line.190"></a> <FONT color="green">191</FONT> * @return the percentile value<a name="line.191"></a> <FONT color="green">192</FONT> * @throws IllegalArgumentException if the parameters are not valid or the<a name="line.192"></a> <FONT color="green">193</FONT> * input array is null<a name="line.193"></a> <FONT color="green">194</FONT> */<a name="line.194"></a> <FONT color="green">195</FONT> public double evaluate(final double[] values, final int begin,<a name="line.195"></a> <FONT color="green">196</FONT> final int length, final double p) {<a name="line.196"></a> <FONT color="green">197</FONT> <a name="line.197"></a> <FONT color="green">198</FONT> test(values, begin, length);<a name="line.198"></a> <FONT color="green">199</FONT> <a name="line.199"></a> <FONT color="green">200</FONT> if ((p > 100) || (p <= 0)) {<a name="line.200"></a> <FONT color="green">201</FONT> throw MathRuntimeException.createIllegalArgumentException(<a name="line.201"></a> <FONT color="green">202</FONT> "out of bounds quantile value: {0}, must be in (0, 100]", p);<a name="line.202"></a> <FONT color="green">203</FONT> }<a name="line.203"></a> <FONT color="green">204</FONT> if (length == 0) {<a name="line.204"></a> <FONT color="green">205</FONT> return Double.NaN;<a name="line.205"></a> <FONT color="green">206</FONT> }<a name="line.206"></a> <FONT color="green">207</FONT> if (length == 1) {<a name="line.207"></a> <FONT color="green">208</FONT> return values[begin]; // always return single value for n = 1<a name="line.208"></a> <FONT color="green">209</FONT> }<a name="line.209"></a> <FONT color="green">210</FONT> double n = length;<a name="line.210"></a> <FONT color="green">211</FONT> double pos = p * (n + 1) / 100;<a name="line.211"></a> <FONT color="green">212</FONT> double fpos = Math.floor(pos);<a name="line.212"></a> <FONT color="green">213</FONT> int intPos = (int) fpos;<a name="line.213"></a> <FONT color="green">214</FONT> double dif = pos - fpos;<a name="line.214"></a> <FONT color="green">215</FONT> double[] sorted = new double[length];<a name="line.215"></a> <FONT color="green">216</FONT> System.arraycopy(values, begin, sorted, 0, length);<a name="line.216"></a> <FONT color="green">217</FONT> Arrays.sort(sorted);<a name="line.217"></a> <FONT color="green">218</FONT> <a name="line.218"></a> <FONT color="green">219</FONT> if (pos < 1) {<a name="line.219"></a> <FONT color="green">220</FONT> return sorted[0];<a name="line.220"></a> <FONT color="green">221</FONT> }<a name="line.221"></a> <FONT color="green">222</FONT> if (pos >= n) {<a name="line.222"></a> <FONT color="green">223</FONT> return sorted[length - 1];<a name="line.223"></a> <FONT color="green">224</FONT> }<a name="line.224"></a> <FONT color="green">225</FONT> double lower = sorted[intPos - 1];<a name="line.225"></a> <FONT color="green">226</FONT> double upper = sorted[intPos];<a name="line.226"></a> <FONT color="green">227</FONT> return lower + dif * (upper - lower);<a name="line.227"></a> <FONT color="green">228</FONT> }<a name="line.228"></a> <FONT color="green">229</FONT> <a name="line.229"></a> <FONT color="green">230</FONT> /**<a name="line.230"></a> <FONT color="green">231</FONT> * Returns the value of the quantile field (determines what percentile is<a name="line.231"></a> <FONT color="green">232</FONT> * computed when evaluate() is called with no quantile argument).<a name="line.232"></a> <FONT color="green">233</FONT> *<a name="line.233"></a> <FONT color="green">234</FONT> * @return quantile<a name="line.234"></a> <FONT color="green">235</FONT> */<a name="line.235"></a> <FONT color="green">236</FONT> public double getQuantile() {<a name="line.236"></a> <FONT color="green">237</FONT> return quantile;<a name="line.237"></a> <FONT color="green">238</FONT> }<a name="line.238"></a> <FONT color="green">239</FONT> <a name="line.239"></a> <FONT color="green">240</FONT> /**<a name="line.240"></a> <FONT color="green">241</FONT> * Sets the value of the quantile field (determines what percentile is<a name="line.241"></a> <FONT color="green">242</FONT> * computed when evaluate() is called with no quantile argument).<a name="line.242"></a> <FONT color="green">243</FONT> *<a name="line.243"></a> <FONT color="green">244</FONT> * @param p a value between 0 < p <= 100<a name="line.244"></a> <FONT color="green">245</FONT> * @throws IllegalArgumentException if p is not greater than 0 and less<a name="line.245"></a> <FONT color="green">246</FONT> * than or equal to 100<a name="line.246"></a> <FONT color="green">247</FONT> */<a name="line.247"></a> <FONT color="green">248</FONT> public void setQuantile(final double p) {<a name="line.248"></a> <FONT color="green">249</FONT> if (p <= 0 || p > 100) {<a name="line.249"></a> <FONT color="green">250</FONT> throw MathRuntimeException.createIllegalArgumentException(<a name="line.250"></a> <FONT color="green">251</FONT> "out of bounds quantile value: {0}, must be in (0, 100]", p);<a name="line.251"></a> <FONT color="green">252</FONT> }<a name="line.252"></a> <FONT color="green">253</FONT> quantile = p;<a name="line.253"></a> <FONT color="green">254</FONT> }<a name="line.254"></a> <FONT color="green">255</FONT> <a name="line.255"></a> <FONT color="green">256</FONT> /**<a name="line.256"></a> <FONT color="green">257</FONT> * {@inheritDoc}<a name="line.257"></a> <FONT color="green">258</FONT> */<a name="line.258"></a> <FONT color="green">259</FONT> @Override<a name="line.259"></a> <FONT color="green">260</FONT> public Percentile copy() {<a name="line.260"></a> <FONT color="green">261</FONT> Percentile result = new Percentile();<a name="line.261"></a> <FONT color="green">262</FONT> copy(this, result);<a name="line.262"></a> <FONT color="green">263</FONT> return result;<a name="line.263"></a> <FONT color="green">264</FONT> }<a name="line.264"></a> <FONT color="green">265</FONT> <a name="line.265"></a> <FONT color="green">266</FONT> /**<a name="line.266"></a> <FONT color="green">267</FONT> * Copies source to dest.<a name="line.267"></a> <FONT color="green">268</FONT> * <p>Neither source nor dest can be null.</p><a name="line.268"></a> <FONT color="green">269</FONT> *<a name="line.269"></a> <FONT color="green">270</FONT> * @param source Percentile to copy<a name="line.270"></a> <FONT color="green">271</FONT> * @param dest Percentile to copy to<a name="line.271"></a> <FONT color="green">272</FONT> * @throws NullPointerException if either source or dest is null<a name="line.272"></a> <FONT color="green">273</FONT> */<a name="line.273"></a> <FONT color="green">274</FONT> public static void copy(Percentile source, Percentile dest) {<a name="line.274"></a> <FONT color="green">275</FONT> dest.quantile = source.quantile;<a name="line.275"></a> <FONT color="green">276</FONT> }<a name="line.276"></a> <FONT color="green">277</FONT> <a name="line.277"></a> <FONT color="green">278</FONT> }<a name="line.278"></a> </PRE> </BODY> </HTML>