<?xml version="1.0" encoding="UTF-8"?> <helpdocument version="1.0"> <!-- * This file is part of the LibreOffice project. * * This Source Code Form is subject to the terms of the Mozilla Public * License, v. 2.0. If a copy of the MPL was not distributed with this * file, You can obtain one at http://mozilla.org/MPL/2.0/. * * This file incorporates work covered by the following license notice: * * Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. See the NOTICE file distributed * with this work for additional information regarding copyright * ownership. The ASF licenses this file to you under the Apache * License, Version 2.0 (the "License"); you may not use this file * except in compliance with the License. You may obtain a copy of * the License at http://www.apache.org/licenses/LICENSE-2.0 . --> <meta> <topic id="textsbasicshared03080202xml" indexer="include" status="PUBLISH"> <title id="tit" xml-lang="en-US">Log Function</title> <filename>/text/sbasic/shared/03080202.xhp</filename> </topic> </meta> <body> <section id="log"> <bookmark xml-lang="en-US" branch="index" id="bm_id3149416"> <bookmark_value>Log function</bookmark_value> </bookmark> <h1 id="hd_id3149416"><link href="text/sbasic/shared/03080202.xhp">Log Function (BASIC)</link></h1> <paragraph id="par_id3145066" role="paragraph" xml-lang="en-US">Returns the natural logarithm of a number.</paragraph> </section> <embed href="text/sbasic/shared/00000003.xhp#functsyntax"/> <bascode> <paragraph id="par_id3154760" role="bascode" xml-lang="en-US">Log (Number)</paragraph> </bascode> <embed href="text/sbasic/shared/00000003.xhp#functvalue"/> <paragraph id="par_id3150791" localize="false" role="paragraph">Double</paragraph> <embed href="text/sbasic/shared/00000003.xhp#functparameters"/> <paragraph id="par_id3151041" role="paragraph" xml-lang="en-US"> <emph>Number:</emph> Any numeric expression that you want to calculate the natural logarithm for.</paragraph> <paragraph id="par_id3150869" role="paragraph" xml-lang="en-US">The natural logarithm is the logarithm to the base e. Base e is a constant with an approximate value of 2.718282...</paragraph> <paragraph id="par_id3153968" role="paragraph" xml-lang="en-US">You can calculate logarithms to any base (n) for any number (x) by dividing the natural logarithm of x by the natural logarithm of n, as follows:</paragraph> <paragraph id="par_id3145420" role="paragraph" xml-lang="en-US">Log<sub>n</sub>(x) = Log(x) / Log(n)</paragraph> <embed href="text/sbasic/shared/00000003.xhp#errorcode"/> <embed href="text/sbasic/shared/00000003.xhp#err5"/> <embed href="text/sbasic/shared/00000003.xhp#functexample"/> <bascode> <paragraph id="par_idm1341571344" role="bascode" localize="false" xml-lang="en-US">Sub ExampleLogExp</paragraph> <paragraph id="par_idm1341570112" role="bascode" localize="false" xml-lang="en-US">Dim a As Double</paragraph> <paragraph id="par_idm1341568880" role="bascode" localize="false" xml-lang="en-US">Dim Const b1=12.345e12</paragraph> <paragraph id="par_idm1341567648" role="bascode" localize="false" xml-lang="en-US">Dim Const b2=1.345e34</paragraph> <paragraph id="par_idm1341566416" role="bascode" localize="false" xml-lang="en-US"> a=Exp( Log(b1)+Log(b2) )</paragraph> <paragraph id="par_id3149262" role="bascode" xml-lang="en-US"> MsgBox "" & a & chr(13) & (b1*b2) ,0,"Multiplication by logarithm function"</paragraph> <paragraph id="par_idm1341563312" role="bascode" localize="false" xml-lang="en-US">End Sub</paragraph> </bascode> </body> </helpdocument>