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24<helpdocument version="1.0">
25<meta>
26<topic id="textsbasicshared03080202xml" indexer="include" status="PUBLISH">
27<title id="tit" xml-lang="en-US">Log Function [Runtime]</title>
28<filename>/text/sbasic/shared/03080202.xhp</filename>
29</topic>
30</meta>
31<body>
32<section id="log">
33<bookmark xml-lang="en-US" branch="index" id="bm_id3149416">
34<bookmark_value>Log function</bookmark_value>
35</bookmark>
36<paragraph role="heading" id="hd_id3149416" xml-lang="en-US" level="1" l10n="U" oldref="1"><link href="text/sbasic/shared/03080202.xhp" name="Log Function [Runtime]">Log Function [Runtime]</link></paragraph>
37<paragraph role="paragraph" id="par_id3145066" xml-lang="en-US" l10n="U" oldref="2">Returns the natural logarithm of a number.</paragraph>
38</section>
39<paragraph role="heading" id="hd_id3159414" xml-lang="en-US" level="2" l10n="U" oldref="3">Syntax:</paragraph>
40<paragraph role="paragraph" id="par_id3154760" xml-lang="en-US" l10n="U" oldref="4">Log (Number)</paragraph>
41<paragraph role="heading" id="hd_id3149457" xml-lang="en-US" level="2" l10n="U" oldref="5">Return value:</paragraph>
42<paragraph role="paragraph" id="par_id3150791" xml-lang="en-US" l10n="U" oldref="6">Double</paragraph>
43<paragraph role="heading" id="hd_id3151211" xml-lang="en-US" level="2" l10n="U" oldref="7">Parameters:</paragraph>
44<paragraph role="paragraph" id="par_id3151041" xml-lang="en-US" l10n="U" oldref="8">
45<emph>Number:</emph> Any numeric expression that you want to calculate the natural logarithm for.</paragraph>
46<paragraph role="paragraph" id="par_id3150869" xml-lang="en-US" l10n="U" oldref="9">The natural logarithm is the logarithm to the base e. Base e is a constant with an approximate value of 2.718282...</paragraph>
47<paragraph role="paragraph" id="par_id3153968" xml-lang="en-US" l10n="U" oldref="10">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>
48<paragraph role="paragraph" id="par_id3145420" xml-lang="en-US" l10n="U" oldref="11">Log n(x) = Log(x) / Log(n)</paragraph>
49<embed href="text/sbasic/shared/00000003.xhp#errorcode"/>
50<embed href="text/sbasic/shared/00000003.xhp#err5"/>
51<paragraph role="heading" id="hd_id3155131" xml-lang="en-US" level="2" l10n="U" oldref="12">Example:</paragraph>
52<paragraph role="paragraph" id="par_id3152463" xml-lang="en-US" l10n="U" oldref="13">Sub ExampleLogExp</paragraph>
53<paragraph role="paragraph" id="par_id3145750" xml-lang="en-US" l10n="U" oldref="14">Dim a as Double</paragraph>
54<paragraph role="paragraph" id="par_id3151116" xml-lang="en-US" l10n="U" oldref="15">Dim const b1=12.345e12</paragraph>
55<paragraph role="paragraph" id="par_id3146985" xml-lang="en-US" l10n="U" oldref="16">Dim const b2=1.345e34</paragraph>
56<paragraph role="paragraph" id="par_id3148616" xml-lang="en-US" l10n="U" oldref="17">a=Exp( Log(b1)+Log(b2) )</paragraph>
57<paragraph role="paragraph" id="par_id3149262" xml-lang="en-US" l10n="U" oldref="18">MsgBox "" &amp; a &amp; chr(13) &amp; (b1*b2) ,0,"Multiplication by logarithm function"</paragraph>
58<paragraph role="paragraph" id="par_id3155411" xml-lang="en-US" l10n="U" oldref="19">end sub</paragraph>
59</body>
60</helpdocument>
61