1<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" 2 3 version="1.0"> 4 5<xsl:output method="text"/> 6 7 8 9<!-- Author: Bob DuCharme --> 10 11<!-- Reference: http://www.xml.com/pub/a/2001/05/07/xsltmath.html --> 12 13<!-- Description: Compute pi. Based on Leibniz's algorithm that 14 15 pi/4 = 1 - 1/3 + 1/5 - 1/7 + 1/9 - 1/11... which I did as 16 17 pi = 4 - 4/3 + 4/5 - 4/7 + 4/9 - 4/11... 18 19--> 20 21 22 23<xsl:variable name="iterations" select="4500"/> 24 25 26 27<xsl:template name="pi"> 28 29 <!-- named template called by main template below --> 30 31 <xsl:param name="i">1</xsl:param> 32 33 <xsl:param name="piValue">0</xsl:param> 34 35 36 37 <xsl:choose> 38 39 <!-- If there are more iterations to do, add the passed 40 41 value of pi to another round of calculations. --> 42 43 <xsl:when test="$i <= $iterations"> 44 45 <xsl:call-template name="pi"> 46 47 <xsl:with-param name="i" select="$i + 4"/> 48 49 <xsl:with-param name="piValue" 50 51 select="$piValue + (4 div $i) - (4 div ($i + 2))"/> 52 53 </xsl:call-template> 54 55 </xsl:when> 56 57 58 59 <!-- If no more iterations to do, add 60 61 computed value to result tree. --> 62 63 <xsl:otherwise> 64 65 <xsl:value-of select="$piValue"/> 66 67 </xsl:otherwise> 68 69 70 71 </xsl:choose> 72 73 74 75</xsl:template> 76 77 78 79 80 81<xsl:template match="/"> 82 83 <xsl:call-template name="pi"/> 84 85</xsl:template> 86 87 <!-- 88 * Licensed to the Apache Software Foundation (ASF) under one 89 * or more contributor license agreements. See the NOTICE file 90 * distributed with this work for additional information 91 * regarding copyright ownership. The ASF licenses this file 92 * to you under the Apache License, Version 2.0 (the "License"); 93 * you may not use this file except in compliance with the License. 94 * You may obtain a copy of the License at 95 * 96 * http://www.apache.org/licenses/LICENSE-2.0 97 * 98 * Unless required by applicable law or agreed to in writing, software 99 * distributed under the License is distributed on an "AS IS" BASIS, 100 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 101 * See the License for the specific language governing permissions and 102 * limitations under the License. 103 --> 104 105</xsl:stylesheet> 106