helpcontent2/source/text/sbasic/shared/03080202.xhp

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  34 <helpdocument version="1.0">
  35 <meta>
  36 <topic id="textsbasicshared03080202xml" indexer="include" status="PUBLISH">
  37 <title id="tit" xml-lang="en-US">Log Function [Runtime]</title>
  38 <filename>/text/sbasic/shared/03080202.xhp</filename>
  39 </topic>
  40 <history>
  41 <created date="2003-10-31T00:00:00">Sun Microsystems, Inc.</created>
  42 <lastedited date="2004-08-24T13:28:25">converted from old format - fpe</lastedited>
  43 </history>
  44 </meta>
  45 <body>
  46 <section id="log">
  47 <bookmark xml-lang="en-US" branch="index" id="bm_id3149416"><bookmark_value>Log function</bookmark_value>
  48 </bookmark>
  49 <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>
  50 <paragraph role="paragraph" id="par_id3145066" xml-lang="en-US" l10n="U" oldref="2">Returns the natural logarithm of a number.</paragraph>
  51 </section>
  52 <paragraph role="heading" id="hd_id3159414" xml-lang="en-US" level="2" l10n="U" oldref="3">Syntax:</paragraph>
  53 <paragraph role="paragraph" id="par_id3154760" xml-lang="en-US" l10n="U" oldref="4">Log (Number)</paragraph>
  54 <paragraph role="heading" id="hd_id3149457" xml-lang="en-US" level="2" l10n="U" oldref="5">Return value:</paragraph>
  55 <paragraph role="paragraph" id="par_id3150791" xml-lang="en-US" l10n="U" oldref="6">Double</paragraph>
  56 <paragraph role="heading" id="hd_id3151211" xml-lang="en-US" level="2" l10n="U" oldref="7">Parameters:</paragraph>
  57 <paragraph role="paragraph" id="par_id3151041" xml-lang="en-US" l10n="U" oldref="8">
  58 <emph>Number:</emph> Any numeric expression that you want to calculate the natural logarithm for.</paragraph>
  59 <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>
  60 <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>
  61 <paragraph role="paragraph" id="par_id3145420" xml-lang="en-US" l10n="U" oldref="11">Log n(x) = Log(x) / Log(n)</paragraph>
  62 <embed href="text/sbasic/shared/00000003.xhp#errorcode"/>
  63 <embed href="text/sbasic/shared/00000003.xhp#err5"/>
  64 <paragraph role="heading" id="hd_id3155131" xml-lang="en-US" level="2" l10n="U" oldref="12">Example:</paragraph>
  65 <paragraph role="paragraph" id="par_id3152463" xml-lang="en-US" l10n="U" oldref="13">Sub ExampleLogExp</paragraph>
  66 <paragraph role="paragraph" id="par_id3145750" xml-lang="en-US" l10n="U" oldref="14">Dim a as Double</paragraph>
  67 <paragraph role="paragraph" id="par_id3151116" xml-lang="en-US" l10n="U" oldref="15">Dim const b1=12.345e12</paragraph>
  68 <paragraph role="paragraph" id="par_id3146985" xml-lang="en-US" l10n="U" oldref="16">Dim const b2=1.345e34</paragraph>
  69 <paragraph role="paragraph" id="par_id3148616" xml-lang="en-US" l10n="U" oldref="17">a=Exp( Log(b1)+Log(b2) )</paragraph>
  70 <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>
  71 <paragraph role="paragraph" id="par_id3155411" xml-lang="en-US" l10n="U" oldref="19">end sub</paragraph>
  72 </body>
  73 </helpdocument>